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Molecules, Volume 16, Issue 4 (April 2011) – 53 articles , Pages 2743-3455

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242 KiB  
Article
Molecular Characterization of Arabinoxylans from Hull-Less Barley Milling Fractions
by Xueling Zheng, Limin Li and Xiaoxi Wang
Molecules 2011, 16(4), 2743-2753; https://doi.org/10.3390/molecules16042743 - 24 Mar 2011
Cited by 29 | Viewed by 6554
Abstract
Arabinoxylans were prepared from different hull-less barley milling fractions (bran, shorts and flour). The yields of hull-less bran arabinoxylan (HBB-AX), shorts arabinoxylan (HBS-AX) and flour arabinoxylan (HBF-AX) were 8.42%, 4.08% and 2.13% respectively. Sugar composition analysis showed that arabinose and xylose were the [...] Read more.
Arabinoxylans were prepared from different hull-less barley milling fractions (bran, shorts and flour). The yields of hull-less bran arabinoxylan (HBB-AX), shorts arabinoxylan (HBS-AX) and flour arabinoxylan (HBF-AX) were 8.42%, 4.08% and 2.13% respectively. Sugar composition analysis showed that arabinose and xylose were the main sugars. HBF-AX had the highest Ara/Xyl ratio, followed by HBS-AX and HBB-AX. Size exclusion chromatography analysis (HPSEC) showed that HBF-AX had the highest molecular weight, followed by HBS-AX and HBB-AX, which had the lowest molecular weight. Aqueous solutions of HBB-AX, HBS-AX and HBF-AX had higher molecular weight(Mw) than in 0.5 mol/L NaOH and 1.0 mol/L NaOH. Dynamic light scattering analysis (DLS) showed that HBB-AX, HBS-AX and HBF-AX had existed in two states in distilled water, 0.5 mol/LNaOH, 1.0 mol/L NaOH, and DMSO/H2O (90/10), an unaggregated state and an aggregated state, with the latter predominating. Full article
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251 KiB  
Article
In-Vitro Antagonistic Characteristics of Crude Aqueous and Methanolic Extracts of Garcinia kola (Heckel) Seeds against Some Vibrio Bacteria
by Dambudzo Penduka, Omobola O. Okoh and Anthony I. Okoh
Molecules 2011, 16(4), 2754-2765; https://doi.org/10.3390/molecules16042754 - 24 Mar 2011
Cited by 14 | Viewed by 6894
Abstract
The methanolic and aqueous extracts of Garcinia kola seeds were screened for their anti-Vibrio activities against 50 Vibrio isolates obtained from wastewater final effluents in the Eastern Cape Province, South Africa. The crude extracts at 10 mg/mL exhibited appreciable inhibitory activities against [...] Read more.
The methanolic and aqueous extracts of Garcinia kola seeds were screened for their anti-Vibrio activities against 50 Vibrio isolates obtained from wastewater final effluents in the Eastern Cape Province, South Africa. The crude extracts at 10 mg/mL exhibited appreciable inhibitory activities against most of the test Vibrio isolates, with zones of inhibition ranging from 10–19 mm for methanol extract and 8–15 mm for the aqueous extracts. The minimum inhibitory concentrations (MIC) of the methanol extract varied from 0.313 to 2.5 mg/mL while that for the aqueous extract was 10 mg/mL for all the susceptible Vibrio isolates. Rate of kill assay of the methanolic extracts against three selected Vibrio species showed bacteriostatic activities against all of them achieving 58% and 60% (Vibrio vulnificus AL042); 68% and 69% (Vibrio parahaemolyticus AL049); and 70% and 78% (Vibrio fluvialis AL040) killing of the test bacteria at 3× and 4 ×MIC values, respectively, after 2 h exposure time. We conclude that Garcinia kola seeds hold promise as a potential source of therapeutic compounds of relevance in Vibrio infections management. Full article
(This article belongs to the Section Natural Products Chemistry)
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301 KiB  
Article
Antifeedant Triterpenoids from the Seeds and Bark of Lansium domesticum cv Kokossan (Meliaceae)
by Tri Mayanti, Roekmiati Tjokronegoro, Unang Supratman, Mat Ropi Mukhtar, Khalijah Awang and A. Hamid A. Hadi
Molecules 2011, 16(4), 2785-2795; https://doi.org/10.3390/molecules16042785 - 29 Mar 2011
Cited by 40 | Viewed by 7282
Abstract
Two tetranortriterpenoids, kokosanolide A (1) and C (2) were isolated from the seeds and three onoceranoid-type triterpenoids: kokosanolide B (3), 8,14-secogammacera-7,14-diene-3,21-dione (4) and a 1.5:0.5 mixture of 8,14-secogammacera-7,14(27)-diene-3,21-dione (5) and compound 4 were isolated [...] Read more.
Two tetranortriterpenoids, kokosanolide A (1) and C (2) were isolated from the seeds and three onoceranoid-type triterpenoids: kokosanolide B (3), 8,14-secogammacera-7,14-diene-3,21-dione (4) and a 1.5:0.5 mixture of 8,14-secogammacera-7,14(27)-diene-3,21-dione (5) and compound 4 were isolated from the bark of kokossan (Lansium domesticum). Complete 1H- and 13C-NMR data of the triterpenoids 1-5 are reported. The triterpenoids’ structures were elucidated primarily by means of high field 1D- and 2D-NMR, IR and HRMS spectral data. Triterpenoids 1-5 exhibited moderate to strong antifeedant activity against the fourth instar larvae of Epilachna vigintioctopunctata. Full article
(This article belongs to the Collection Bioactive Compounds)
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217 KiB  
Article
Cytotoxic Metabolites from the Soil-Derived Fungus Exophiala Pisciphila
by Cui-Cui Wang, Hai-Zhou Liu, Ming Liu, Yu-Yan Zhang, Tian-Tian Li and Xiu-Kun Lin
Molecules 2011, 16(4), 2796-2801; https://doi.org/10.3390/molecules16042796 - 30 Mar 2011
Cited by 7 | Viewed by 7595
Abstract
A new polyketide compound 1 and a new naturally occurring chromone derivative 2, along with two known indole alkaloids 34 were characterized from the ethyl acetate extract of a soil-derived fungal strain, Exophiala pisciphila PHF-9. The structures of compounds 1 [...] Read more.
A new polyketide compound 1 and a new naturally occurring chromone derivative 2, along with two known indole alkaloids 34 were characterized from the ethyl acetate extract of a soil-derived fungal strain, Exophiala pisciphila PHF-9. The structures of compounds 14 were established by detailed spectroscopic analysis and comparison with literature data. The absolute configuration of 1 was determined by a modified Mosher’s method. Compound 1 exhibited moderate cytotoxicity against A-549, Hela, PANC-28 and BEL-7402 cell lines. Full article
(This article belongs to the Collection Bioactive Compounds)
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250 KiB  
Article
General Pathway for a Convenient One-Pot Synthesis of Trifluoromethyl-Containing 2-amino-7-alkyl(aryl/heteroaryl)-1,8-naphthyridines and Fused Cycloalkane Analogues
by Helio G. Bonacorso, Rosália Andrighetto, Nícolas Krüger, Nilo Zanatta and Marcos A. P. Martins
Molecules 2011, 16(4), 2817-2832; https://doi.org/10.3390/molecules16042817 - 30 Mar 2011
Cited by 13 | Viewed by 9455
Abstract
A convenient and general method for the synthesis in 26–73% yields of a new series of 7-alkyl(aryl/heteroaryl)-2-amino-5-trifluoromethyl-1,8-naphthyridines from direct cyclocondensation reactions of 4-alkoxy-1,1,1-trifluoroalk-3-en-2-ones [CF3C(O)CH=C(R1)OR, where R1 = H, Me, Ph, 4-MePh, 4-OMePh, 4-FPh, 4-BrPh, 4-NO2Ph, 2-furyl, [...] Read more.
A convenient and general method for the synthesis in 26–73% yields of a new series of 7-alkyl(aryl/heteroaryl)-2-amino-5-trifluoromethyl-1,8-naphthyridines from direct cyclocondensation reactions of 4-alkoxy-1,1,1-trifluoroalk-3-en-2-ones [CF3C(O)CH=C(R1)OR, where R1 = H, Me, Ph, 4-MePh, 4-OMePh, 4-FPh, 4-BrPh, 4-NO2Ph, 2-furyl, 2-thienyl and R = Me, Et] with 2,6-diaminopyridine (2,6-DAP), under mild conditions, is described. Another synthetic route also allowed the synthesis of 2-amino-5-trifluoromethyl-cycloalka[b][1,8]naphthyridines in 33–36% yields, from direct or indirect cyclo-condensation reactions of five-, six- and seven-membered 2-trifluoroacetyl-1-methoxy-cycloalkenes with 2,6-DAP. Full article
(This article belongs to the Special Issue Fluorine Chemistry 2016)
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250 KiB  
Article
Synthesis and Herbicidal Activity of 5-(4-Hydroxybenzyl)-2-Thioxoimidazolidin-4-one Esters
by Jintao Han, Jinmin Wang, Hongbo Dong, Jianping Lei, Mingan Wang and Jianxin Fang
Molecules 2011, 16(4), 2833-2845; https://doi.org/10.3390/molecules16042833 - 30 Mar 2011
Cited by 19 | Viewed by 7519
Abstract
A series of novel 5-(4-hydroxybenzyl)-2-thioxoimidazolidin-4-one esters were synthesized under mild conditions by the reaction of 5-(4-hydroxybenzyl)-2-thioxoimidazolidin-4-one and carboxylic acids with DCC and DMAP as the promoters. Their structures were confirmed by 1H-NMR, IR, ESI-MS and elemental analysis. The preliminary bioassy results indicated [...] Read more.
A series of novel 5-(4-hydroxybenzyl)-2-thioxoimidazolidin-4-one esters were synthesized under mild conditions by the reaction of 5-(4-hydroxybenzyl)-2-thioxoimidazolidin-4-one and carboxylic acids with DCC and DMAP as the promoters. Their structures were confirmed by 1H-NMR, IR, ESI-MS and elemental analysis. The preliminary bioassy results indicated that some of compounds exhibit good herbicidal activity against Zea mays, Triticum aestivum and Arabidopsis thaliana. The further greenhouse test showed that compounds 6-16 and 6-28 have 60%, 50% and 50% efficacy against Stellaria media, Echinochloa crus-galli and Setaria viridis at 1,000 g/ha, respectively. Full article
(This article belongs to the Collection Bioactive Compounds)
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294 KiB  
Article
Occurrence and Estimation of trans-Resveratrol in One-Year-Old Canes from Seven Major Chinese Grape Producing Regions
by Ang Zhang, Yulin Fang, Xuan Li, Jiangfei Meng, Hua Wang, Hua Li, Zhenwen Zhang and Zhijun Guo
Molecules 2011, 16(4), 2846-2861; https://doi.org/10.3390/molecules16042846 - 31 Mar 2011
Cited by 41 | Viewed by 7203
Abstract
The concentration of trans-resveratrol in 165 grape cane samples from three major grape production regions and four large distribution centers of Chinese wild Vitis species were determined by reversed-phase high-performance liquid chromatography (HPLC). Among the different genotype groups and purpose of uses, [...] Read more.
The concentration of trans-resveratrol in 165 grape cane samples from three major grape production regions and four large distribution centers of Chinese wild Vitis species were determined by reversed-phase high-performance liquid chromatography (HPLC). Among the different genotype groups and purpose of uses, cultivars of V. vinifera had much higher amounts of trans-resveratrol than did the cultivars of both V. labrusca or V. labrusca and V. vinifera hybrids, and within the V. vinifera species, significantly higher amounts of trans-resveratrol were found in wine grapes compared to table ones. No significant differences were observed between V. labrusca and its hybrids from crosses with V. vinifera, and between red cultivars and white ones (P < 0.05 or P < 0.01). The contents of trans-resveratrol, as a normal constituent occurring in grape canes, in Chinese wild species of V. amurensis, V. pentagona, and V. davidii from their native habitats were also relatively high. Full article
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299 KiB  
Article
Preparation of Silver- and Zinc-Doped Mullite-Based Ceramics Showing Anti-Bacterial Biofilm Properties
by Suhair Saleh, Mutasem O. Taha, Randa N. Haddadin, Duá Marzooqa and Hamdallah Hodali
Molecules 2011, 16(4), 2862-2870; https://doi.org/10.3390/molecules16042862 - 31 Mar 2011
Cited by 14 | Viewed by 5971
Abstract
Zinc- and silver-doped mullite ceramic discs were prepared and tested as potentially resistant materials against bacterial adhesion and biofilm formation. Elemental analysis and X-ray diffraction studies showed that zinc ions were incorporated in the structural framework of the mullite, while silver ions remained [...] Read more.
Zinc- and silver-doped mullite ceramic discs were prepared and tested as potentially resistant materials against bacterial adhesion and biofilm formation. Elemental analysis and X-ray diffraction studies showed that zinc ions were incorporated in the structural framework of the mullite, while silver ions remained outside the mullite crystal lattice, which allowed their slow (0.02 ppm/24 hours) leaching into the surrounding aqueous environment. In agreement with this behavior, silver-doped mullite showed potent resistance against surface attachment of Pseudomonas aeruginosa, while on the other hand, zinc-doped mullite failed to stop bacterial attachment. Full article
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619 KiB  
Article
Cyclic Water Clusters in Tape-Like and Cage-Like Structures
by Qin Huang, Lihong Diao, Chuang Zhang and Fuhou Lei
Molecules 2011, 16(4), 2871-2883; https://doi.org/10.3390/molecules16042871 - 04 Apr 2011
Cited by 6 | Viewed by 4870
Abstract
Controlling the ratio of 2,2′-bpy to benzene-1,3,5-tricarboxylic acid produces two interesting complexes, namely [Co(2,2′-bpy)3] (SO4) 8.5H2O (1) and [Cu2(BTCA) (2,2′-bpy)4] (OH) (2,2′-bpy)0.5·14H2O (2) (H3 [...] Read more.
Controlling the ratio of 2,2′-bpy to benzene-1,3,5-tricarboxylic acid produces two interesting complexes, namely [Co(2,2′-bpy)3] (SO4) 8.5H2O (1) and [Cu2(BTCA) (2,2′-bpy)4] (OH) (2,2′-bpy)0.5·14H2O (2) (H3BTCA = benzene-1,3,5-tricarboxylic acid, 2,2′-bpy = 2,2′-bipyridine). We report the structural evidence in the solid state of discrete lamellar water cluster conformations. These units are found to act as supramolecular glue in the aggregation of cobalt (II) or copper (II) complexes to give three dimensional cage-like networks through hydrogen-bonding. It is interesting that the structure of complex 1 contains a 3D negatively charged cage. Full article
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858 KiB  
Article
Comparison of Various Easy-to-Use Procedures for Extraction of Phenols from Apricot Fruits
by Ondrej Zitka, Jiri Sochor, Otakar Rop, Sylvie Skalickova, Pavlina Sobrova, Josef Zehnalek, Miroslava Beklova, Boris Krska, Vojtech Adam and Rene Kizek
Molecules 2011, 16(4), 2914-2936; https://doi.org/10.3390/molecules16042914 - 04 Apr 2011
Cited by 31 | Viewed by 10247
Abstract
Phenols are broadly distributed in the plant kingdom and are the most abundant secondary metabolites of plants. Plant polyphenols have drawn increasing attention due to their potential antioxidant properties and their marked effects in the prevention of various oxidative stress associated diseases such [...] Read more.
Phenols are broadly distributed in the plant kingdom and are the most abundant secondary metabolites of plants. Plant polyphenols have drawn increasing attention due to their potential antioxidant properties and their marked effects in the prevention of various oxidative stress associated diseases such as cancer. The objective of this study was to investigate a suitable method for determination of protocatechuic acid, 4-aminobenzoic acid, chlorogenic acid, caffeic acid, vanillin, p-coumaric acid, rutin, ferulic acid, quercetin, resveratrol and quercitrin from apricot samples. A high-performance liquid chromatograph with electrochemical and UV detectors was used. The method was optimized in respect to both the separation selectivity of individual phenolic compounds and the maximum sensitivity with the electrochemical detection. The lowest limits of detection (3 S/N) using UV detection were estimated for ferulic acid (3 µM), quercitrin (4 µM) and quercetin (4 µM). Using electrochemical detection values of 27 nM, 40 nM and 37 nM were achieved for ferulic acid, quercitrin and quercetin, respectively. It follows from the acquired results that the coulometric detection under a universal potential of 600 mV is more suitable and sensitive for polyphenols determination than UV detection at a universal wavelength of 260 nm. Subsequently, we tested the influence of solvent composition, vortexing and sonication on separation efficiency. Our results showed that a combination of water, acetone and methanol in 20:20:60 ratio was the most effective for p-aminobenzoic acid, chlorgenic acid, caffeic acid, protocatechuic acid, ferulic acid, rutin, resveratrol and quercetin, in comparison with other solvents. On the other hand, vortexing at 4 °C produced the highest yield. Moreover, we tested the contents of individual polyphenols in the apricot cultivars Mamaria, Mold and LE-1075. The major phenolic compounds were chlorgenic acid and rutin. Chlorgenic acid was found in amounts of 2,302 mg/100 g in cultivar LE-1075, 546 mg/100 g in cultivar Mamaria and 129 mg/100 g in cultivar Mold. Generally, the cultivar LE-1075 produced the highest polyphenol content values, contrary to Mold, which compared to cultivar LE-1075 was quite poor from the point of view of the phenolics content. Full article
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221 KiB  
Article
A New Diterpene Glycoside from Stevia rebaudiana
by Venkata Sai Prakash Chaturvedula and Indra Prakash
Molecules 2011, 16(4), 2937-2943; https://doi.org/10.3390/molecules16042937 - 04 Apr 2011
Cited by 48 | Viewed by 11425
Abstract
From the commercial extract of the leaves of Stevia rebaudiana, a new diterpene glycoside was isolated besides the known steviol glycosides including stevioside, rebaudiosides A-F, rubusoside and dulcoside A. The new compound was identified as 13-[(2-O-β-D-glucopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic [...] Read more.
From the commercial extract of the leaves of Stevia rebaudiana, a new diterpene glycoside was isolated besides the known steviol glycosides including stevioside, rebaudiosides A-F, rubusoside and dulcoside A. The new compound was identified as 13-[(2-O-β-D-glucopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-(2-O-α-L-rhamnopyranosyl-β-D-glucopyranosyl) ester (1) on the basis of extensive spectroscopic (NMR and MS) and chemical studies. Full article
(This article belongs to the Section Natural Products Chemistry)
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279 KiB  
Article
Selective Cytotoxicity of Goniothalamin against Hepatoblastoma HepG2 Cells
by Mothanna Al-Qubaisi, Rosli Rozita, Swee-Keong Yeap, Abdul-Rahman Omar, Abdul-Manaf Ali and Noorjahan B. Alitheen
Molecules 2011, 16(4), 2944-2959; https://doi.org/10.3390/molecules16042944 - 06 Apr 2011
Cited by 119 | Viewed by 14852
Abstract
Liver cancer has become one of the major types of cancer with high mortality and liver cancer is not responsive to the current cytotoxic agents used in chemotherapy. The purpose of this study was to examine the in vitro cytotoxicity of goniothalamin on [...] Read more.
Liver cancer has become one of the major types of cancer with high mortality and liver cancer is not responsive to the current cytotoxic agents used in chemotherapy. The purpose of this study was to examine the in vitro cytotoxicity of goniothalamin on human hepatoblastoma HepG2 cells and normal liver Chang cells. The cytotoxicity of goniothalamin against HepG2 and liver Chang cell was tested using MTT cell viability assay, LDH leakage assay, cell cycle flow cytometry PI analysis, BrdU proliferation ELISA assay and trypan blue dye exclusion assay. Goniothalamin selectively inhibited HepG2 cells [IC50 = 4.6 (±0.23) µM in the MTT assay; IC50 = 5.20 (±0.01) µM for LDH assay at 72 hours], with less sensitivity in Chang cells [IC50 = 35.0 (±0.09) µM for MTT assay; IC50 = 32.5 (±0.04) µM for LDH assay at 72 hours]. In the trypan blue dye exclusion assay, the Viability Indexes were 52 ± 1.73% for HepG2 cells and 62 ± 4.36% for Chang cells at IC50 after 72 hours. Cytotoxicity of goniothalamin was related to inhibition of DNA synthesis, as revealed by the reduction of BrdU incorporation. At 72 hours, the lowest concentration of goniothalamin (2.3 µL) retained 97.6% of normal liver Chang cells proliferation while it reduced HepG2 cell proliferation to 19.8% as compared to control. Besides, goniothalamin caused accumulation of hypodiploid apoptosis and different degree of G2/M arrested as shown in cell cycle analysis by flow cytometry. Goniothalamin selectively killed liver cancer cell through suppression of proliferation and induction of apoptosis. These results suggest that goniothalamin shows potential cytotoxicity against hepatoblastoma HepG2 cells. Full article
(This article belongs to the Section Natural Products Chemistry)
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251 KiB  
Article
Synthesis, Characterization and Spectral Properties of Substituted Tetraphenylporphyrin Iron Chloride Complexes
by Zhi-Cheng Sun, Yuan-Bin She, Yang Zhou, Xu-Feng Song and Kai Li
Molecules 2011, 16(4), 2960-2970; https://doi.org/10.3390/molecules16042960 - 06 Apr 2011
Cited by 93 | Viewed by 17688
Abstract
A series of substituted tetraphenylporphyrin iron chloride complexes [RTPPFe(III)Cl, R=o/p-NO2, o/p-Cl, H, o/p-CH3, o/p-OCH3] were synthesized by a novel universal mixed-solvent method and the [...] Read more.
A series of substituted tetraphenylporphyrin iron chloride complexes [RTPPFe(III)Cl, R=o/p-NO2, o/p-Cl, H, o/p-CH3, o/p-OCH3] were synthesized by a novel universal mixed-solvent method and the spectral properties of free base porphyrins and iron porphyrin compounds were compared with each other. The experimental results showed that the one-pot mixed solvent method was superior to the two-step method in the yields, reaction time and workup of reaction mixtures for the synthesis of iron porphyrin compounds. The highest yields (28.7%-40.4%) of RTPPFe(III)Cl were obtained in the mixed solvents propionic acid, glacial acetic acid and m-nitrotoluene under reflux for 2 h. A detailed analysis of ultraviolet-visible (UV-vis), infrared (IR) and far-infrared (FIR) spectra suggested the transformation from free base porphyrins to iron porphyrins. The red shift of the Soret band in ultraviolet-visible spectra due to the presence of p-nitrophenyl substituents and the blue shift of Fe-Cl bond of TPPFeCl in far-infrared spectra were further explained by the electron transfer and molecular planarity in the porphyrin ring. Full article
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238 KiB  
Article
Catalytic Enantioselective Aryl Transfer to Aldehydes Using Chiral 2,2’-Bispyrrolidine-Based Salan Ligands
by Xuefeng Jia, Aijun Lin, Zhijie Mao, Chengjian Zhu and Yixiang Cheng
Molecules 2011, 16(4), 2971-2981; https://doi.org/10.3390/molecules16042971 - 06 Apr 2011
Cited by 8 | Viewed by 6355
Abstract
Chiral C2-symmetric diamines have emerged as versatile auxiliaries or ligands in numerous asymmetric transformations. Chiral 2,2’-bispyrrolidine-based salan ligands were prepared and applied to the asymmetric aryl transfer to aldehydes with arylboronic acids as the source of transferable aryl groups. The corresponding [...] Read more.
Chiral C2-symmetric diamines have emerged as versatile auxiliaries or ligands in numerous asymmetric transformations. Chiral 2,2’-bispyrrolidine-based salan ligands were prepared and applied to the asymmetric aryl transfer to aldehydes with arylboronic acids as the source of transferable aryl groups. The corresponding diarylmethanols were obtained in high yields with moderate to good enantioselectivitives of up to 83% ee. Full article
(This article belongs to the Special Issue Catalytic Asymmetric Synthesis)
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132 KiB  
Communication
Assessment of the In Vivo Genotoxicity of New Lead Compounds to Treat Sickle Cell Disease
by Jean Leandro Dos Santos, Priscila Longhin Bosquesi, Eliana Aparecida Varanda, Lídia Moreira Lima and Man Chin Chung
Molecules 2011, 16(4), 2982-2989; https://doi.org/10.3390/molecules16042982 - 06 Apr 2011
Cited by 3 | Viewed by 7985
Abstract
The compounds 1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl nitrate (C1), (1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)ethyl nitrate (C2), 3-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)benzyl nitrate (C3), 4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-N-hydroxy-benzenesulfonamide (C4), 4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)benzyl nitrate (C5), and 2-[4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)phenyl]ethyl nitrate (C6 [...] Read more.
The compounds 1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl nitrate (C1), (1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)ethyl nitrate (C2), 3-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)benzyl nitrate (C3), 4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-N-hydroxy-benzenesulfonamide (C4), 4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)benzyl nitrate (C5), and 2-[4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)phenyl]ethyl nitrate (C6) were evaluated with a micronucleus test using mouse peripheral blood to identify new candidate drugs for the treatment of sickle cell disease (SCD) that are safer than hydroxyurea. The compounds induced an average frequency of micronucleated reticulocytes (MNRET) of less than six per 1,000 cells at 12.5, 25, 50, and 100 mg/kg, whereas hydroxyurea induced an average MNRET frequency of 7.8, 9.8, 15, and 33.7 per 1000 cells respectively, at the same concentrations. Compounds C1–C6 are new non-genotoxic in vivo candidate drugs for the treatment of SCD symptoms. Full article
(This article belongs to the Collection Bioactive Compounds)
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289 KiB  
Article
Reactive Oxygen Species-Induced Impairment of Endothelium-Dependent Relaxations in Rat Aortic Rings: Protection by Methanolic Extracts of Phoebe grandis
by Lau Yeh-Siang, Gopal Subramaniam, A. Hamid A. Hadi, Dharmani Murugan and Mohd Rais Mustafa
Molecules 2011, 16(4), 2990-3000; https://doi.org/10.3390/molecules16042990 - 06 Apr 2011
Cited by 6 | Viewed by 6719
Abstract
Generation of reactive oxygen species plays a pivotal role in the development of cardiovascular diseases. The present study describes the effects of the methanolic extract of Phoebe grandis (MPG) stem bark on reactive oxygen species-induced endothelial dysfunction in vitro. Endothelium-dependent (acetylcholine, ACh) [...] Read more.
Generation of reactive oxygen species plays a pivotal role in the development of cardiovascular diseases. The present study describes the effects of the methanolic extract of Phoebe grandis (MPG) stem bark on reactive oxygen species-induced endothelial dysfunction in vitro. Endothelium-dependent (acetylcholine, ACh) and -independent relaxation (sodium nitroprusside, SNP) was investigated from isolated rat aorta of Sprague-Dawley (SD) in the presence of the β-NADH (enzymatic superoxide inducer) and MPG extract. Superoxide anion production in aortic vessels was measured by lucigen chemiluminesence. Thirty minutes incubation of the rat aorta in vitro with β-NADH increased superoxide radical production and significantly inhibited ACh-induced relaxations. Pretreatment with MPG (0.5, 5 and 50 μg/mL) restored the ACh-induced relaxations (Rmax: 92.29% ± 2.93, 91.02% ± 4.54 and 88.31 ± 2.36, respectively) in the presence of β-NADH. MPG was ineffective in reversing the impaired ACh-induced relaxations caused by pyrogallol, a non-enzymatic superoxide generator. Superoxide dismutase (a superoxide scavenger), however, reversed the impaired ACh relaxations induced by both β-NADH and pyrogallol. MPG also markedly inhibited the β-NADH-induced generation of the superoxide radicals. Furthermore, MPG scavenging peroxyl radicals generated by tBuOOH (10−4 M).These results indicate that MPG may improve the endothelium dependent relaxations to ACh through its scavenging activity as well as by inhibiting the NADH/NADPH oxidase induced generation of superoxide anions. Full article
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172 KiB  
Article
Alkaloidal Variation in Cissampelos Capensis (Menispermaceae)
by Helene De Wet, Fanie R. Van Heerden and Ben-Erik Van Wyk
Molecules 2011, 16(4), 3001-3009; https://doi.org/10.3390/molecules16043001 - 07 Apr 2011
Cited by 27 | Viewed by 8932
Abstract
Cissampelos capensis, commonly known by the Afrikaans name “dawidjies” or “dawidjieswortel”, is the most important and best known medicinal plant of the family Menispermaceae used by the Khoisan and other rural people in the western region of South Africa. The main alkaloids [...] Read more.
Cissampelos capensis, commonly known by the Afrikaans name “dawidjies” or “dawidjieswortel”, is the most important and best known medicinal plant of the family Menispermaceae used by the Khoisan and other rural people in the western region of South Africa. The main alkaloids in the leaves, stems and rhizomes were isolated and identified. Several of the main compounds were previously found in species of the related genus Antizoma and this similarity indicates that the two genera are closely related if not congeneric. Bulbocapnine (an aporphine alkaloid), dicentrine (an aporphine alkaloid) and salutaridine (a morphinane alkaloid) were the main alkaloids in the leaves, while bulbocapnine, cissacapine, cycleanine and insularine (the last three are bisbenzyltetrahydro-isoquinoline alkaloids) are the major compounds in the stems. The rhizome contains mostly bisbenzyltetrahydroisoquinoline alkaloids, with 12-O-methylcurine, cissacapine and cycleanine as the main ones. Alkaloids appear to be quite variable within different plant parts and different provenances, as confirmed by the difference in alkaloid patterns between coastal and inland forms of Cissampelos capensis (the morphinane alkaloid salutaridine, for example, is the major leaf alkaloid along the coast but is practically absent from the inland form of the species). The variety of alkaloids identified may contribute to the medicinal value of this species. The data on alkaloidal variation in the species has potential value and practical applications in chemotaxonomy, toxicology and pharmacognosy. Full article
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193 KiB  
Communication
Investigation of the Interactions between the Hydrophobic Cavities of Cyclodextrins and Pullulanase
by Bo Yu, Jinpeng Wang, Huanxin Zhang and Zhengyu Jin
Molecules 2011, 16(4), 3010-3017; https://doi.org/10.3390/molecules16043010 - 07 Apr 2011
Cited by 20 | Viewed by 5158
Abstract
The effects of cyclodextrins and derivatives on the activity and structure of pullulanase were investigated in this study. Our results showed that cyclodextrins and derivatives decreased the activity of pullulanase. This decrease was attributed to the interaction between the hydrophobic cavities of cyclodextrins [...] Read more.
The effects of cyclodextrins and derivatives on the activity and structure of pullulanase were investigated in this study. Our results showed that cyclodextrins and derivatives decreased the activity of pullulanase. This decrease was attributed to the interaction between the hydrophobic cavities of cyclodextrins and pullulanase. The hydrophobic cavity was confirmed to encapsulate the groups of pullulanase molecules by the addition of competitive guests. The results obtained from fluorescence spectroscopy analysis showed that β-CD showed more efficient interactions with pullulanase molecules and the side chain groups of cyclodextrin significantly prevented the interaction between the hydrophobic cavities of β-CD and pullulanase molecules. These findings suggest that the geometric dimension of hydrophobic cavities was crucial for matching between cyclodextrins and pullulanase and steric hindrance caused by side chains led to the decrease of the interaction. Full article
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218 KiB  
Article
A New Abietene Diterpene and Other Constituents from Kaempferia angustifolia Rosc.
by Sook Wah Tang, Mohd Aspollah Sukari, Mawardi Rahmani, Nordin Hj. Lajis and Abdul Manaf Ali
Molecules 2011, 16(4), 3018-3028; https://doi.org/10.3390/molecules16043018 - 07 Apr 2011
Cited by 15 | Viewed by 7970
Abstract
A new abietene diterpene, kaempfolienol (5S,6S,7S,9S,10S,11R,13S-abiet-8(14)-enepenta-6,7,9,11,13-ol, 1), was isolated from a rhizome extract of Kaempferia angustifolia Rosc. along with the known compounds crotepoxide, boesenboxide, zeylenol, 2′-hydroxy-4,4′,6′-trimethoxychalcone, (24S [...] Read more.
A new abietene diterpene, kaempfolienol (5S,6S,7S,9S,10S,11R,13S-abiet-8(14)-enepenta-6,7,9,11,13-ol, 1), was isolated from a rhizome extract of Kaempferia angustifolia Rosc. along with the known compounds crotepoxide, boesenboxide, zeylenol, 2′-hydroxy-4,4′,6′-trimethoxychalcone, (24S)-24-methyl-5α-lanosta-9(11),25-dien-3β-ol, β-sitosterol and β-sitosterol-3-O-β-D-glucopyranoside. The structures of all compounds were elucidated on the basis of mass spectroscopic and NMR data. Zeylenol (2), the major constituent of the plant, was derivatized into diacetate, triacetate and epoxide derivatives through standard organic reactions. The cytotoxic activity of compounds 1, 2 and the zeylenol derivatives was evaluated against the HL-60, MCF-7, HT-29 and HeLa cell lines. Full article
(This article belongs to the Section Natural Products Chemistry)
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1766 KiB  
Article
Preparation and Characterization of Chitin Benzoic Acid Esters
by Lok Ranjan Bhatt, Bo Mi Kim, Kim Hyun, Geu Beum Kwak, Chai Ho Lee and Kyu Yun Chai
Molecules 2011, 16(4), 3029-3036; https://doi.org/10.3390/molecules16043029 - 08 Apr 2011
Cited by 11 | Viewed by 7035
Abstract
Chitin benzoic acid esters were prepared using a phosphoryl mixed anhydride method. The products were characterized by 1H-NMR and FT-IR spectroscopy. FT-IR analysis revealed that the degree of O-acyl substitution of the products was in a range of 1.17–1.83. Morphological surface [...] Read more.
Chitin benzoic acid esters were prepared using a phosphoryl mixed anhydride method. The products were characterized by 1H-NMR and FT-IR spectroscopy. FT-IR analysis revealed that the degree of O-acyl substitution of the products was in a range of 1.17–1.83. Morphological surface changes in the parent molecule due to the introduction of benzoic acid moieties were observed by scanning electron microscopy. The surface of the products was porous, in contrast to the sheet-shape of the parent molecules. The solubility of the products, which improved with increased degree of acid substitution, was tested in various organic solvents. Full article
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137 KiB  
Article
An Antimicrobial Compound Isolated from Cinnamomum Iners Leaves with Activity against Methicillin-Resistant Staphylococcus Aureus
by Fazlina Mustaffa, Jayant Indurkar, Sabariah Ismail, Marina Shah and Sharif Mahsufi Mansor
Molecules 2011, 16(4), 3037-3047; https://doi.org/10.3390/molecules16043037 - 08 Apr 2011
Cited by 28 | Viewed by 7716
Abstract
This study was designed to investigate the antimicrobial activity of Cinnamomum iners standardized leave methanolic extract (CSLE), its fractions and isolated compounds. CSLE and fractions were subjected to disc diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests using different Gram [...] Read more.
This study was designed to investigate the antimicrobial activity of Cinnamomum iners standardized leave methanolic extract (CSLE), its fractions and isolated compounds. CSLE and fractions were subjected to disc diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests using different Gram positive and Gram negative bacteria and yeast. Within the series of fractions tested, the ethyl acetate fraction was the most active, particularly against methicillin resistant Staphylococcus aureus (MRSA) and Escherichia coli, with MIC values of 100 and 200 µg/mL, respectively. The active compound in this fraction was isolated and identified as xanthorrhizol [5-(1, 5-dimethyl-4-hexenyl)-2-methylphenol] by various spectroscopic techniques. The overall results of this study provide evidence that Cinnamomum iners leaves extract as well as the isolated compound xanthorrhizol exhibit antimicrobial activity for both Gram negative and Gram positive pathogens, especially against MRSA strains. Full article
(This article belongs to the Section Natural Products Chemistry)
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533 KiB  
Article
2D-DIGE Proteomic Analysis of Changes in Estrogen/Progesterone-Induced Rat Breast Hyperplasia upon Treatment with the Mongolian Remedy RuXian-I
by Zhong-Chao Wang, Du E, De-Ligen Batu, Ya-Latu Saixi, Bin Zhang and Li-Qun Ren
Molecules 2011, 16(4), 3048-3065; https://doi.org/10.3390/molecules16043048 - 08 Apr 2011
Cited by 9 | Viewed by 8282
Abstract
RuXian-I has traditionally been used as a remedy for breast hyperplasia in the Inner Mongolia Autonomous Region of China. As a first step toward the investigation of biomarkers associated with RuXian-I treatment, a proteome-wide analysis of rat breast tissue was conducted. First, rat [...] Read more.
RuXian-I has traditionally been used as a remedy for breast hyperplasia in the Inner Mongolia Autonomous Region of China. As a first step toward the investigation of biomarkers associated with RuXian-I treatment, a proteome-wide analysis of rat breast tissue was conducted. First, rat breast hyperplasia was induced by injection of estradiol and progesterone. After treatment with RuXian-I, there is a marked decrease in the hyperplasia, as can be shown by decreases in the nipple diameter and the pathological changes in breast. Subsequently, we used an approach that integrates size-based 2D-DIGE, MALDI-TOF/TOF-MS, and bioinformatics to analyze data from the control group, the model group and the RuXian-I treatment group. Using this approach, seventeen affected proteins were identified. Among these, 15 (including annexin A1, annexin A2, superoxide dismutase [Mn], peroxiredoxin-1, translationally-controlled tumor protein and a B-crystallin) were significantly up-regulated in the model group and down-regulated upon treatment with RuXian-I, and two (Tpil protein and myosin-4) have the opposite change trend. The expression of annexin A1 was confirmed using immunohistochemistry. The expression of superoxide dismutase (SOD) activity was confirmed biochemically. These results indicated that RuXian-I treats rat breast hyperplasia through regulation of cell cycle, immune system, metabolic, signal transduction, etc. The differential expressions of these proteins (annexin A1, superoxide dismutase [Mn], alpha B-crystallins and translationally controlled tumor protein, among others) were associated with occurrence and metastasis of breast cancer. These findings might provide not only far-reaching valuable insights into the mechanism of RuXian-I action, but also leads for prognosis and diagnosis of breast hyperplasia and breast cancer. Full article
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209 KiB  
Article
New Solid Phase Synthesis of Distamycin Analogues
by Drozdowska Danuta
Molecules 2011, 16(4), 3066-3076; https://doi.org/10.3390/molecules16043066 - 11 Apr 2011
Cited by 12 | Viewed by 5217 | Correction
Abstract
A novel and straightforward solid phase synthesis of distamycin analogues containing benzene units has been developed. Full article
(This article belongs to the Section Medicinal Chemistry)
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244 KiB  
Article
Components and Insecticidal Activity against the Maize Weevils of Zanthoxylum schinifolium Fruits and Leaves
by Cheng Fang Wang, Kai Yang, Hai Ming Zhang, Jie Cao, Rui Fang, Zhi Long Liu, Shu Shan Du, Yong Yan Wang, Zhi Wei Deng and Ligang Zhou
Molecules 2011, 16(4), 3077-3088; https://doi.org/10.3390/molecules16043077 - 13 Apr 2011
Cited by 87 | Viewed by 11594
Abstract
In our screening program for new agrochemicals from Chinese medicinal herbs and wild plants, Zanthoxylum schinifolium essential oils were found to possess strong insecticidal activity against the maize weevil Sitophilus zeamais. The essential oils of Z. schinifolium fruits and leaves were extracted [...] Read more.
In our screening program for new agrochemicals from Chinese medicinal herbs and wild plants, Zanthoxylum schinifolium essential oils were found to possess strong insecticidal activity against the maize weevil Sitophilus zeamais. The essential oils of Z. schinifolium fruits and leaves were extracted via hydrodistillation and investigated by GC and GC-MS. Estragole (69.52%) was the major compound of the essential oil of fresh fruits, followed by linalool (8.63%) and limonene (4.34%) and 94.33% of the total components were monoterpenoids. The main components of the essential oil of fresh leaves were linalool (12.94%), ar-tumerone (8.95%), limonene (6.45%) and elixene (5.43%) and only 50.62% were monoterpenoids. However, the essential oil from purchased fruits contained linalool (33.42%), limonene (13.66%) and sabinene (5.72%), followed by estragole (4.67%), nerol (4.56%) and 4-terpineol (4.27%). Estragole, linalool and sabinene were separated and purified by silica gel column chromatography and preparative thin layer chromatography, and further identified by means of physicochemical and spectrometric analysis. The essential oil from the fresh fruits (LD50 = 15.93 μg/adult) possessed two times more toxicity to the insects compared with that of fresh leaves (LD50 = 35.31 μg/adult). Estragole, linalool and sabinene exhibited contact activity against S. zeamais with LD50 values of 17.63, 13.90 and 23.98 μg/adult, respectively. The essential oils of Z. schinifolium possessed strong fumigant toxicity against S. zeamais adults with LC50 values of 13.19 mg/L (fresh fruits), 24.04 mg/L (fresh leaves) and 17.63 mg/L (purchased fruits). Estragole, linalool and sabinene also exhibited strong fumigant toxicity against the maize weevils with LC50 values of 14.10, 10.46 and 9.12 mg/L, respectively. Full article
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Article
Chemically Induced Photoswitching of Fluorescent Probes—A General Concept for Super-Resolution Microscopy
by Ulrike Endesfelder, Sebastian Malkusch, Benjamin Flottmann, Justine Mondry, Piotr Liguzinski, Peter J. Verveer and Mike Heilemann
Molecules 2011, 16(4), 3106-3118; https://doi.org/10.3390/molecules16043106 - 13 Apr 2011
Cited by 87 | Viewed by 15462
Abstract
We review fluorescent probes that can be photoswitched or photoactivated and are suited for single-molecule localization based super-resolution microscopy. We exploit the underlying photochemical mechanisms that allow photoswitching of many synthetic organic fluorophores in the presence of reducing agents, and study the impact [...] Read more.
We review fluorescent probes that can be photoswitched or photoactivated and are suited for single-molecule localization based super-resolution microscopy. We exploit the underlying photochemical mechanisms that allow photoswitching of many synthetic organic fluorophores in the presence of reducing agents, and study the impact of these on the photoswitching properties of various photoactivatable or photoconvertible fluorescent proteins. We have identified mEos2 as a fluorescent protein that exhibits reversible photoswitching under various imaging buffer conditions and present strategies to characterize reversible photoswitching. Finally, we discuss opportunities to combine fluorescent proteins with organic fluorophores for dual-color photoswitching microscopy. Full article
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262 KiB  
Article
Lancifoliaine, a New Bisbenzylisoquinoline from the Bark of Litsea lancifolia
by Syazreen Nadia Sulaiman, Mat Ropi Mukhtar, A Hamid A Hadi, Khalijah Awang, Hazrina Hazni, Azeana Zahari, Marc Litaudon, Kazumasa Zaima and Hiroshi Morita
Molecules 2011, 16(4), 3119-3127; https://doi.org/10.3390/molecules16043119 - 13 Apr 2011
Cited by 18 | Viewed by 7400
Abstract
A new bisbenzylisoquinoline, lancifoliaine (1), together with seven known alkaloids – N-allyllaurolitsine (2), reticuline (3), actinodaphnine, norboldine, pallidine, cassythicine and boldine – were isolated from the stem bark of Litsea lancifolia (Lauraceae). In addition to that [...] Read more.
A new bisbenzylisoquinoline, lancifoliaine (1), together with seven known alkaloids – N-allyllaurolitsine (2), reticuline (3), actinodaphnine, norboldine, pallidine, cassythicine and boldine – were isolated from the stem bark of Litsea lancifolia (Lauraceae). In addition to that of lancifoliaine, complete 13C-NMR data of N-allyl-laurolitsine (2) was also reported. The alkaloidal structures were elucidated by means of high field 1D- and 2D-NMR IR, UV, and LCMS-IT-TOF spectral data. N-Allyllaurolitsine (2) showed a moderate vasorelaxant activity on isolated rat aorta. Full article
(This article belongs to the Section Natural Products Chemistry)
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423 KiB  
Article
On the Reducible Character of Haldane-Radić Enzyme Kinetics to Conventional and Logistic Michaelis-Menten Models
by Mihai V. Putz
Molecules 2011, 16(4), 3128-3145; https://doi.org/10.3390/molecules16043128 - 13 Apr 2011
Cited by 12 | Viewed by 9999
Abstract
The conceptual and practical issues regarding the reduction of the Haldane-Radić enzymic mechanism, specific for cholinesterase kinetics, to the consecrated or logistically modified Michaelis-Menten kinetics, specific for some mutant enzymes, are here clarified as due to the limited initial substrate concentration, through detailed [...] Read more.
The conceptual and practical issues regarding the reduction of the Haldane-Radić enzymic mechanism, specific for cholinesterase kinetics, to the consecrated or logistically modified Michaelis-Menten kinetics, specific for some mutant enzymes, are here clarified as due to the limited initial substrate concentration, through detailed initial rate and progress curve analysis, even when other classical conditions for such equivalence are not entirely fulfilled. Full article
(This article belongs to the Special Issue Enzyme-Catalyzed Reactions)
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270 KiB  
Communication
Screening for Compounds with Aromatase Inhibiting Activities from Atractylodes macrocephala Koidz
by Hai Jiang, Jing Shi and Yuanyuan Li
Molecules 2011, 16(4), 3146-3151; https://doi.org/10.3390/molecules16043146 - 14 Apr 2011
Cited by 46 | Viewed by 8283
Abstract
Ten compounds were isolated from the dichloromethane extract of Atractylodes macrocephala and their aromatase inhibiting activities were tested using an in vitro fluorescent-based aromatase assay. The results indicated that atractylenolide I (1), atractylenolide II (2) and atractylenolide III ( [...] Read more.
Ten compounds were isolated from the dichloromethane extract of Atractylodes macrocephala and their aromatase inhibiting activities were tested using an in vitro fluorescent-based aromatase assay. The results indicated that atractylenolide I (1), atractylenolide II (2) and atractylenolide III (3) had inhibition ratios of 94.56 ± 0.70%, 90.93 ± 1.41% and 86.31 ± 8.46%, respectively, at a concentration of 10 μM. We conclude from our results that atractylenolide and its derivates may serve as potential aromatase inhibitors (AIs) and thus merit continued study in the future. Full article
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250 KiB  
Article
Antioxidant Activities of Melittis melissophyllum L. (Lamiaceae)
by Biljana Kaurinovic, Mira Popovic, Sanja Vlaisavljevic and Milena Raseta
Molecules 2011, 16(4), 3152-3167; https://doi.org/10.3390/molecules16043152 - 14 Apr 2011
Cited by 10 | Viewed by 6515
Abstract
Extracts of Melittis melissophyllum leaves in ether, chloroform, ethyl acetate, n-butanol and water were evaporated to dryness and dissolved in 50% ethanol to make 10% (w/v) solutions. The potential protective action of the extracts was assessed by the corresponding in vitro and [...] Read more.
Extracts of Melittis melissophyllum leaves in ether, chloroform, ethyl acetate, n-butanol and water were evaporated to dryness and dissolved in 50% ethanol to make 10% (w/v) solutions. The potential protective action of the extracts was assessed by the corresponding in vitro and in vivo tests. In the in vitro experiments extracts were tested as potential scavengers of free radicals (DPPH, O2·-, NO, and OH radicals), as well as inhibitors of liposomal peroxidation (LPx). The results obtained show that all extracts (exept n-BuOH extract) are good scavengers of radicals and reduce LPx intensity in liposomes, which points to their protective (antioxidant) activity. In vivo experiments were concerned with antioxidant systems (activities of GSHPx, GSHR, Px, CAT, XOD, GSH content and intensity of LPx) in liver homogenate and blood-hemolysate of experimental animals after their treatment with extracts of M. melissophyllum leaves, or in combination with CCl4. On the basis of the results obtained it can be concluded that the examined extracts have protective (antioxidative) effect and this antioxidative behaviour is more pronounced in liver than in blood-hemolysate. The reason is probably the fact that liver contains other enzymatic systems, which can also participate in the antioxidative mechanism. Of all the extracts the H2O one showed the highest protective activity. Full article
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306 KiB  
Article
Syntheses, Structures and Antimicrobial Activities of bis(Imino)acenaphthene (BIAN) Imidazolium Salts
by Rachel R. Butorac, Salem S. Al-Deyab and Alan H. Cowley
Molecules 2011, 16(4), 3168-3178; https://doi.org/10.3390/molecules16043168 - 15 Apr 2011
Cited by 19 | Viewed by 8713
Abstract
The syntheses of four new bis(imino)acenaphthene (BIAN) imidazolium chlorides are reported, three of which have been structurally characterized. The synthesis of a new, structurally authenticated BIAN ligand is also described. We report the results of the use of these BIAN imidazolium salts as [...] Read more.
The syntheses of four new bis(imino)acenaphthene (BIAN) imidazolium chlorides are reported, three of which have been structurally characterized. The synthesis of a new, structurally authenticated BIAN ligand is also described. We report the results of the use of these BIAN imidazolium salts as antimicrobials against the pathogens S. aureus, B. subtilis, E. coli and P. aeruginosa. The antimicrobial efficacies were particularly high for the N-(2,6-diisopropylphenyl)- and N-(mesityl)- substituted BIAN imidazolium salts (MIC values < 0.6 μg/mL). Full article
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703 KiB  
Article
Induction of Intracellular Ca2+ and pH Changes in Sf9 Insect Cells by Rhodojaponin-III, A Natural Botanic Insecticide Isolated from Rhododendron molle
by Xing-An Cheng, Jian-Jun Xie, Mei-Ying Hu, Yan-Bo Zhang and Jing-Fei Huang
Molecules 2011, 16(4), 3179-3196; https://doi.org/10.3390/molecules16043179 - 15 Apr 2011
Cited by 11 | Viewed by 9741
Abstract
Many studies on intracellular calcium ([Ca2+]i) and intracellular pH (pHi) have been carried out due to their importance in regulation of different cellular functions. However, most of the previous studies are focused on human or mammalian cells. [...] Read more.
Many studies on intracellular calcium ([Ca2+]i) and intracellular pH (pHi) have been carried out due to their importance in regulation of different cellular functions. However, most of the previous studies are focused on human or mammalian cells. The purpose of the present study was to characterize the effect of Rhodojaponin-III (R-III) on [Ca2+]i and pHi and the proliferation of Sf9 cells. R-III strongly inhibited Sf9 cells proliferation with a time- and dose-dependent manner. Flow cytometry established that R-III interfered with Sf9 cells division and arrested them in G2/M. By using confocal scanning technique, effects of R-III on intracellular free calcium ([Ca2+]i) and intracellular pH (pHi) in Sf9 cells were determined. R-III induced a significant dose-dependent (1, 10, 100, 200 μg/mL) increase in [Ca2+]i and pHi of Sf9 cells in presence of Ca2+-containing solution (Hanks) and an irreversible decrease in the absence of extra cellular Ca2+. We also found that both extra cellular Ca2+ and intracellular Ca2+ stores contributed to the increase of [Ca2+]i, because completely treating Sf9 cells with CdCl2 (5 mM), a Ca2+ channels blocker, R-III (100 μg/mL) induced a transient elevation of [Ca2+]i in case of cells either in presence of Ca2+ containing or Ca2+ free solution. In these conditions, pHi showed similar changes with that of [Ca2+]i on the whole. Accordingly, we supposed that there was a certain linkage for change of [Ca2+]i, cell cycle arrest, proliferation inhibition in Sf9 cells induced by R-III. Full article
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275 KiB  
Article
Antioxidant Properties and Antioxidant Compounds of Various Extracts from the Edible Basidiomycete Grifola Frondosa (Maitake)
by Jan-Ying Yeh, Li-Hui Hsieh, Kaun-Tzer Wu and Cheng-Fang Tsai
Molecules 2011, 16(4), 3197-3211; https://doi.org/10.3390/molecules16043197 - 15 Apr 2011
Cited by 84 | Viewed by 12356
Abstract
Grifola frondosa is an edible mushroom currently available in Taiwan. Ethanolic, cold-water and hot-water extracts were prepared and their antioxidant properties were investigated. At 1 mg/mL, G. frondosa T1 and T2 cold-water extracts showed high reducing powers of 1.02 and 0.50, respectively. Chelating [...] Read more.
Grifola frondosa is an edible mushroom currently available in Taiwan. Ethanolic, cold-water and hot-water extracts were prepared and their antioxidant properties were investigated. At 1 mg/mL, G. frondosa T1 and T2 cold-water extracts showed high reducing powers of 1.02 and 0.50, respectively. Chelating abilities on ferrous ions of G. frondosa T1 and T2 were higher for cold-water extracts than for ethanolic and hot-water extracts. For the scavenging ability on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, G. frondosa T1 and T2 extracts were effective in the following order: ethanolic > hot-water > cold-water. The G. frondosa hot-water extract showed high scavenging ability on superoxide anions. Total phenols, flavonoids, ascorbic acid and α-tocopherol are the major antioxidant components found in the various G. frondosa extracts. Based on EC50 values ( Full article
(This article belongs to the Special Issue Antioxidants)
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267 KiB  
Article
Kazinol Q from Broussonetia kazinoki Enhances Cell Death Induced by Cu(ll) through Increased Reactive Oxygen Species
by Bai-Luh Wei, Ying-Chieh Chen and Hsue-Yin Hsu
Molecules 2011, 16(4), 3212-3221; https://doi.org/10.3390/molecules16043212 - 15 Apr 2011
Cited by 12 | Viewed by 6762
Abstract
The ability of the flavan kazinol Q (KQ) to induce DNA breakage in the presence of Cu(II) was examined by agarose gel electrophoresis using supercoiled plasmid DNA. In KQ-mediated DNA breakage reaction, the involvement of reactive oxygen species (ROS), H [...] Read more.
The ability of the flavan kazinol Q (KQ) to induce DNA breakage in the presence of Cu(II) was examined by agarose gel electrophoresis using supercoiled plasmid DNA. In KQ-mediated DNA breakage reaction, the involvement of reactive oxygen species (ROS), H2O2 and O2 - was established by the inhibition of DNA breakage by catalase and revealed DNA breakage by superoxide dismutase (SOD). The cell viability of gastric carcinoma SCM-1 cells treated with various concentrations of KQ was significantly decreased by cotreatment with Cu(II). Treatment of SCM-1 cells with 300 μM Cu(II) enhanced the necrosis induced by 100 μM KQ. Treatment of SCM-1 cells with 100 mM KQ in the presence of 300 mM Cu(II) increased the generation of H2O2. Taken together, the above finding suggested that KQ cotreatment with Cu(II) produced increased amounts of H2O2, thus enhancing subsequent cell death due to necrosis. Full article
(This article belongs to the Section Natural Products Chemistry)
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386 KiB  
Article
Structure Identification of Euphorbia Factor L3 and Its Induction of Apoptosis through the Mitochondrial Pathway
by Jian-Ye Zhang, Yong-Ju Liang, Hu-Biao Chen, Li-Sheng Zheng, Yan-Jun Mi, Fang Wang, Xiao-Qin Zhao, Xiao-Kun Wang, Hui Zhang and Li-Wu Fu
Molecules 2011, 16(4), 3222-3231; https://doi.org/10.3390/molecules16043222 - 15 Apr 2011
Cited by 19 | Viewed by 7321
Abstract
In this article, we have focused on the structure identification of Euphorbia factor L3 belonging to the lathyrane diterpenoids isolated from Caper Euphorbia Seed. Its anticancer activity in vitro against lung cancer A549 cells was also investigated and the IC50 values were [...] Read more.
In this article, we have focused on the structure identification of Euphorbia factor L3 belonging to the lathyrane diterpenoids isolated from Caper Euphorbia Seed. Its anticancer activity in vitro against lung cancer A549 cells was also investigated and the IC50 values were 34.04 ± 3.99 μM. Furthermore, Euphorbia factor L3 could induce apoptosis in A549 cells via the mitochondrial pathway including loss of mitochondrial potential and release of cytochrome c. Full article
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444 KiB  
Article
Kaempferol and Kaempferol Rhamnosides with Depigmenting and Anti-Inflammatory Properties
by Ho Sik Rho, Amal Kumar Ghimeray, Dae Sung Yoo, Soo Mi Ahn, Sun Sang Kwon, Keun Ha Lee, Dong Ha Cho and Jae Youl Cho
Molecules 2011, 16(4), 3338-3344; https://doi.org/10.3390/molecules16043338 - 18 Apr 2011
Cited by 99 | Viewed by 9760
Abstract
The objective of this study was to examine the biological activity of kaempferol and its rhamnosides. We isolated kaempferol (1), a-rhamnoisorobin (2), afzelin (3), and kaempferitrin (4) as pure compounds by far-infrared (FIR) irradiation of [...] Read more.
The objective of this study was to examine the biological activity of kaempferol and its rhamnosides. We isolated kaempferol (1), a-rhamnoisorobin (2), afzelin (3), and kaempferitrin (4) as pure compounds by far-infrared (FIR) irradiation of kenaf (Hibiscus cannabinus L.) leaves. The depigmenting and anti-inflammatory activity of the compounds was evaluated by analyzing their structure-activity relationships. The order of the inhibitory activity with regard to depigmentation and nitric oxide (NO) production was kaempferol (1) > a-rhamnoisorobin (2) > afzelin (3) > kaempferitrin (4). However, a-rhamnoisorobin (2) was more potent than kaempferol (1) in NF-kB-mediated luciferase assays. From these results, we conclude that the 3-hydroxyl group of kaempferol is an important pharmacophore and that additional rhamnose moieties affect the biological activity negatively. Full article
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140 KiB  
Article
Identification of Diterpenoid Alkaloids from the Roots of Aconitum kusnezoffii Reihcb.
by Ning Xu, De-Feng Zhao, Xin-Miao Liang, Hua Zhang and Yuan-Sheng Xiao
Molecules 2011, 16(4), 3345-3350; https://doi.org/10.3390/molecules16043345 - 19 Apr 2011
Cited by 16 | Viewed by 7347
Abstract
Three diterpenoid alkaloids, including an unreported compound, were isolated from the roots of Aconitum kusnezoffii Reichb. On the basis of spectral analysis, these three compounds were determined to be 1,15-dimethoxy-3-hydroxy-14-benzoyl-16-ketoneoline, benzoylaconine and aconitine. Full article
(This article belongs to the Special Issue Alkaloids: Novel Therapeutic Perspectives)
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277 KiB  
Article
Three New Oblongolides from Phomopsis sp. XZ-01, an Endophytic Fungus from Camptotheca acuminate
by Ting Lin, Guang Hui Wang, Xiang Lin, Zhi Yu Hu, Quan Cheng Chen, Yang Xu, Xiao Kun Zhang and Hai Feng Chen
Molecules 2011, 16(4), 3351-3359; https://doi.org/10.3390/molecules16043351 - 19 Apr 2011
Cited by 14 | Viewed by 8546
Abstract
Four new metabolites, including three new oblongolides named C1, P1, and X1 (1-3) and 6-hydroxyphomodiol (10), along with eight known compounds – oblongolides B (4), C (5), D (6), O ( [...] Read more.
Four new metabolites, including three new oblongolides named C1, P1, and X1 (1-3) and 6-hydroxyphomodiol (10), along with eight known compounds – oblongolides B (4), C (5), D (6), O (7), P (8) and U (9), (3R,4aR,5S,6R)-6-hydroxy-5-methylramulosin (11), and (3R)-5-methylmellein (12) – were isolated from the endophytic fungal strain Phomopsis sp. XZ-01 of Camptotheca acuminate. Their structures were elucidated by spectroscopic analyses, including 1H- and 13C-NMR, 2D NMR (HSQC, HMBC, 1H-1H COSY and NOESY) and HR-FT-MS. Cytotoxic activities of these compounds were evaluated. Some of them showed weak selective activities. Full article
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195 KiB  
Article
Antitussive Activity of Pseudostellaria heterophylla (Miq.) Pax Extracts and Improvement in Lung Function via Adjustment of Multi-Cytokine Levels
by Wensheng Pang, Siding Lin, Qiwen Dai, Hongcheng Zhang and Juan Hu
Molecules 2011, 16(4), 3360-3370; https://doi.org/10.3390/molecules16043360 - 19 Apr 2011
Cited by 52 | Viewed by 7356
Abstract
Pseudostellaria heterophylla (Miq.) Pax is one of the most widespread herbal and healthcare products in China. Extensive clinical use has shown that it has functions which “strengthens qi and generates saliva, moistens the lung and relieves cough”. The ethyl acetate fraction extracted from [...] Read more.
Pseudostellaria heterophylla (Miq.) Pax is one of the most widespread herbal and healthcare products in China. Extensive clinical use has shown that it has functions which “strengthens qi and generates saliva, moistens the lung and relieves cough”. The ethyl acetate fraction extracted from the roots of the plant Pseudostellaria heterophylla exhibited a dose-dependent antitussive effect between 100 to 500 mg/kg. At a dose of 400 mg/kg, the ethyl acetate fraction treatment markedly prolonged the cough latent period and reduced the number of coughs in a guinea pig model induced by citric acid. Fall lung airway resistance, rise in dynamic lung compliance, decreased serum levels of IL-8, GM-CSF, TNF-α, and ET-1 in rat model of stable phase chronic obstructive pulmonary disease induced by cigarette smoke exposure were also observed. These results suggest that ethyl acetate fraction has antitussive activity related to its improvement in lung function via attenuation of airway inflammation by adjustment of multi-cytokine levels. Full article
(This article belongs to the Section Natural Products Chemistry)
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290 KiB  
Article
Salidroside Attenuates Hydrogen Peroxide-Induced Cell Damage Through a cAMP-Dependent Pathway
by Shuang Guan, Wei Wang, Jing Lu, Wenhui Qian, Guoren Huang, Xuming Deng and Xuelin Wang
Molecules 2011, 16(4), 3371-3379; https://doi.org/10.3390/molecules16043371 - 19 Apr 2011
Cited by 17 | Viewed by 8959
Abstract
Salidroside, a major component of Rhodiola rosea L., has shown various pharmacological functions, including antioxidant effects, but the signal transduction pathway of its antioxidant effects is not very clear. In this study, we found that salidroside could attenuate hydrogen peroxide (H [...] Read more.
Salidroside, a major component of Rhodiola rosea L., has shown various pharmacological functions, including antioxidant effects, but the signal transduction pathway of its antioxidant effects is not very clear. In this study, we found that salidroside could attenuate hydrogen peroxide (H2O2)-induced HL-7702 cell damage, inhibit H2O2-induced cytosolic free Ca2+ ([Ca2+]i) elevation, scavenge reactive oxygen species (ROS) and increase 3’-5’-cyclic adenosine monophosphate (cAMP) level in a dose-dependent manner, but it couldn’t influence 3’-5’-cyclic guanosine monophosphate (cGMP) levels. Therefore, these results indicated that the antioxidant effects of salidroside were associated with down-regulation of [Ca2+]i, ROS occur via a cAMP-dependent pathway. Full article
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390 KiB  
Article
Simple and Efficient Synthesis of Racemic 2-(tert-Butoxycarbon-ylamino)-2-methyl-3-(1H-1,2,4-triazol-1-yl)propanoic Acid, a New Derivative of β-(1,2,4-Triazol-1-yl)alanine
by Younas Aouine, Hassane Faraj, Anouar Alami, Abdelilah El-Hallaoui, Abdelrhani Elachqar and Abdelali Kerbal
Molecules 2011, 16(4), 3380-3390; https://doi.org/10.3390/molecules16043380 - 19 Apr 2011
Cited by 4 | Viewed by 8568
Abstract
A simple synthetic approach to racemic N-tert-butyloxycarbonyl-2-methyl-3-(1H-1,2,4-triazol-1-yl)alanine (5) in four steps and 68% overall yield starting from oxazoline derivative 1 is reported. This synthesis involves the alkylation of 1H-1,2,4-triazole with an O-tosyloxazoline derivative, [...] Read more.
A simple synthetic approach to racemic N-tert-butyloxycarbonyl-2-methyl-3-(1H-1,2,4-triazol-1-yl)alanine (5) in four steps and 68% overall yield starting from oxazoline derivative 1 is reported. This synthesis involves the alkylation of 1H-1,2,4-triazole with an O-tosyloxazoline derivative, followed by an oxazoline ring-opening reaction and oxidation of the N-protected β‑aminoalcohol by potassium permanganate. Full article
(This article belongs to the Section Organic Chemistry)
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281 KiB  
Article
Seasonal Variation of Bioactive Alkaloid Contents in Macleaya microcarpa (Maxim.) Fedde
by Kristýna Pěnčíková, Jana Urbanová, Pavel Musil, Eva Táborská and Jana Gregorová
Molecules 2011, 16(4), 3391-3401; https://doi.org/10.3390/molecules16043391 - 20 Apr 2011
Cited by 31 | Viewed by 7670
Abstract
Macleaya microcarpa (Maxim.) Fedde belongs to the genus Macleaya, family Papaveraceae. Together with the better known and more frequently studied species M. cordata (Willd.) R. Br. it is a main source of quaternary benzo[c]phenanthridine alkaloids. Using HPLC we determined the content [...] Read more.
Macleaya microcarpa (Maxim.) Fedde belongs to the genus Macleaya, family Papaveraceae. Together with the better known and more frequently studied species M. cordata (Willd.) R. Br. it is a main source of quaternary benzo[c]phenanthridine alkaloids. Using HPLC we determined the content of eight isoquinoline alkaloids in the aerial and underground parts of 1-, 2-, 12- and 13-year old plants and followed their changes during the vegetative period. The dominant alkaloid of all samples collected in the end of this period was allocryptopine (3.8–13.6 mg/g for aerial parts, 24.2–48.9 mg/g for underground parts). Chelerythrine, sanguinarine and protopine were also present in both parts of the plant. Additionally, measurable concentrations of chelilutine (CL), chelirubine (CR), macarpine (MA) and sanguirubine (SR) were detected in underground parts. The most important finding was that contents of CR, CL, SR and MA in the 12- and 13-year old plant roots were significantly higher (approximately 3-fold for CR, 6-fold for CL, 5-fold for SR, and at least 14-fold for MA) than in 1- or 2-year old plants. The proportion of individual alkaloids in aerial and underground parts thus changed significantly during the vegetative period. Full article
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433 KiB  
Article
N-Cyanomethylnorboldine: A New Aporphine Isolated from Alseodaphne perakensis (Lauraceae)
by Mohd Azlan Nafiah, Mat Ropi Mukhtar, Hanita Omar, Kartini Ahmad, Hiroshi Morita, Marc Litaudon, Khalijah Awang and A. Hamid A. Hadi
Molecules 2011, 16(4), 3402-3409; https://doi.org/10.3390/molecules16043402 - 20 Apr 2011
Cited by 12 | Viewed by 6636
Abstract
A phytochemical study of the bark of Alseodaphne perakensis has yielded three aporphine alkaloids: the new compound N-cyanomethylnorboldine (1), and the two known alkaloids N-methyllaurotetanine (2) and norboldine (3). The isolation was achieved by [...] Read more.
A phytochemical study of the bark of Alseodaphne perakensis has yielded three aporphine alkaloids: the new compound N-cyanomethylnorboldine (1), and the two known alkaloids N-methyllaurotetanine (2) and norboldine (3). The isolation was achieved by chromatographic techniques and the structural elucidation was performed via spectral methods, notably 1D- and 2D-NMR, UV, IR, and HRFABMS. The vasorelaxation activity of compound 1 has been studied. Full article
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177 KiB  
Article
Synthesis and Anticancer Activity of Some Novel Tetralin-6-yl-pyrazoline, 2-Thioxopyrimidine, 2-Oxopyridine, 2-Thioxo-pyridine and 2-Iminopyridine Derivatives
by Ebtehal S. Al-Abdullah
Molecules 2011, 16(4), 3410-3419; https://doi.org/10.3390/molecules16043410 - 20 Apr 2011
Cited by 53 | Viewed by 8008
Abstract
The title compounds were prepared by reaction of 6-acetyltetralin (1) with different aromatic aldehydes 2a-c, namely 2,6-dichlorobenzaldehyde, 2,6-diflouro-benzaldehyde, and 3-ethoxy-4-hydroxybenzaldehyde, to yield the corresponding a,b-unsaturated ketones 3a-c. Compound 3b was reacted with hydrazine hydrate to yield the corresponding 2-pyrazoline 4 [...] Read more.
The title compounds were prepared by reaction of 6-acetyltetralin (1) with different aromatic aldehydes 2a-c, namely 2,6-dichlorobenzaldehyde, 2,6-diflouro-benzaldehyde, and 3-ethoxy-4-hydroxybenzaldehyde, to yield the corresponding a,b-unsaturated ketones 3a-c. Compound 3b was reacted with hydrazine hydrate to yield the corresponding 2-pyrazoline 4, while compounds 3a,b reacted with thiourea to afford the 2-thioxopyrimidine derivatives 5a,b, respectively. The reaction of 1, and the aromatic aldehydes 2a-c with ethyl cyanoacetate, 2-cyano-thioacetamide or malononitrile in the presence of ammonium acetate yielded the corresponding 2-oxopyridines 6a,b, 2-thioxopyridines 7a-c or 2-iminopyridines 8a,b, respectively. The newly prepared compounds were evaluated for anticancer activity against two human tumor cell lines. Compound 3a showed the highest potency with IC50 = 3.5 and 4.5 μg/mL against a cervix carcinoma cell line (Hela) and breast carcinoma cell line (MCF7), respectively. Full article
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214 KiB  
Article
Proline-Catalysed Amination Reactions in Cyclic Carbonate Solvents
by Christopher Beattie, Michael North and Pedro Villuendas
Molecules 2011, 16(4), 3420-3432; https://doi.org/10.3390/molecules16043420 - 21 Apr 2011
Cited by 69 | Viewed by 6861
Abstract
Propylene carbonate is shown to be an environmentally friendly and sustainable replacement for dichloromethane and acetonitrile in proline-catalysed a-hydrazinations of aldehydes and ketones. Enantioselectivities comparable to those obtained in conventional solvents or ionic liquids can be obtained, even when using a lower catalyst [...] Read more.
Propylene carbonate is shown to be an environmentally friendly and sustainable replacement for dichloromethane and acetonitrile in proline-catalysed a-hydrazinations of aldehydes and ketones. Enantioselectivities comparable to those obtained in conventional solvents or ionic liquids can be obtained, even when using a lower catalyst loading. Full article
(This article belongs to the Special Issue Catalytic Asymmetric Synthesis)
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100 KiB  
Article
Antioxidant, Total Phenolic Content and Cytotoxicity Evaluation of Selected Malaysian Plants
by Suhailah Wasman Qader, Mahmood Ameen Abdulla, Lee Suan Chua, Nigar Najim, Mazatulikhma Mat Zain and Salehhuddin Hamdan
Molecules 2011, 16(4), 3433-3443; https://doi.org/10.3390/molecules16043433 - 21 Apr 2011
Cited by 148 | Viewed by 15692
Abstract
Aqueous and ethanol extracts of different traditional Malaysian plants (Polygonum minus, Andrographis paniculata, Curcuma xanthorrhiza, Momordica charantia and Strobilanthes crispus) were evaluated for their antioxidant properties, total phenolic content and cytotoxic activity. Antioxidant activity was evaluated by using 1,1-diphenyl-1-picrylhydrazyl (DPPH) [...] Read more.
Aqueous and ethanol extracts of different traditional Malaysian plants (Polygonum minus, Andrographis paniculata, Curcuma xanthorrhiza, Momordica charantia and Strobilanthes crispus) were evaluated for their antioxidant properties, total phenolic content and cytotoxic activity. Antioxidant activity was evaluated by using 1,1-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. The results showed that ethanol extracts contain high antioxidant activities compared to aqueous extracts. The findings exhibited a strong correlation between antioxidant activity and the total phenol contents. In addition, all the plant extracts showed non-toxic effects against a normal human lung fibroblast cell line (Hs888Lu). Although traditionally aqueous extracts are used, we determined that ethanol extracts usually achieved better activity in the assays. Full article
(This article belongs to the Section Natural Products Chemistry)
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204 KiB  
Article
Antioxidant Compounds from Propolis Collected in Anhui, China
by Haisha Yang, Yuqiong Dong, Huijing Du, Haiming Shi, Yunhua Peng and Xiaobo Li
Molecules 2011, 16(4), 3444-3455; https://doi.org/10.3390/molecules16043444 - 21 Apr 2011
Cited by 134 | Viewed by 10408
Abstract
The antioxidant activities of the chloroform, ethyl acetate and n-butanol extract fractions from propolis collected in Anhui, China were evaluated in this study. The ethyl acetate fraction contained the highest amount of total phenolics and total flavonoids, and showed the greatest 1,1-diphenyl-2-picrylhydrazyl [...] Read more.
The antioxidant activities of the chloroform, ethyl acetate and n-butanol extract fractions from propolis collected in Anhui, China were evaluated in this study. The ethyl acetate fraction contained the highest amount of total phenolics and total flavonoids, and showed the greatest 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging capacities and Ferric Reducing/Antioxidant Power (FRAP). The antioxidant activity of twenty-two compounds isolated from the ethyl acetate fraction was also evaluated using the above-mentioned three assays. The results indicated that phenolics contributed to the antioxidant activity of propolis collected in Anhui, China. Therefore, propolis collected in Anhui, China and its phenolics might be used as a natural antioxidant. Full article
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Review

Jump to: Research

208 KiB  
Review
The Effect of Tannins on Mediterranean Ruminant Ingestive Behavior: The Role of the Oral Cavity
by Elsa Lamy, Harshadrai Rawel, Florian J. Schweigert, Fernando Capela e Silva, Ana Ferreira, Ana Rodrigues Costa, Célia Antunes, André Martinho Almeida, Ana Varela Coelho and Elvira Sales-Baptista
Molecules 2011, 16(4), 2766-2784; https://doi.org/10.3390/molecules16042766 - 25 Mar 2011
Cited by 60 | Viewed by 11211
Abstract
Sheep, cattle and goat are domestic ruminants of significant economic interest in the Mediterranean region. Although sharing the same pasture ranges, they ingest different plants and plant parts and, consequently different levels of tannins. This suggests an ability to detect and adapt ingestion [...] Read more.
Sheep, cattle and goat are domestic ruminants of significant economic interest in the Mediterranean region. Although sharing the same pasture ranges, they ingest different plants and plant parts and, consequently different levels of tannins. This suggests an ability to detect and adapt ingestion according to animal physiological limits of tolerance for plant secondary metabolites. This review will detail the effects of dietary tannins on feeding behavior, and the role of the oral cavity in this process, with focus on such ruminant species. The role of salivary protein profile in tannin perception in the oral cavity, and as a defense mechanism, will be discussed. Full article
(This article belongs to the Special Issue Tannins)
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222 KiB  
Review
Effects of Panax ginseng on Tumor Necrosis Factor-α-Mediated Inflammation: A Mini-Review
by Davy CW Lee and Allan SY Lau
Molecules 2011, 16(4), 2802-2816; https://doi.org/10.3390/molecules16042802 - 30 Mar 2011
Cited by 98 | Viewed by 11180
Abstract
Panax ginseng is one of the most commonly used Chinese medicines in China, Asia and Western countries. The beneficial effects of ginseng have been attributed to the biological activities of its constituents, the ginsenosides. In this review, we summarize recent publications on the [...] Read more.
Panax ginseng is one of the most commonly used Chinese medicines in China, Asia and Western countries. The beneficial effects of ginseng have been attributed to the biological activities of its constituents, the ginsenosides. In this review, we summarize recent publications on the anti-inflammatory effects of ginseng extracts and ginsenosides on cellular responses triggered by different inducers including endotoxin, tumor necrosis factor-alpha (TNF-α), interferon-gamma and other stimuli. Proinflammatory cytokines, chemokines, adhesion molecules and mediators of inflammation including inducible nitric oxide synthase, cyclooxygenase-2 and nitric oxide orchestrate the inflammatory response. Ginseng extracts and ginsenosides including Rb1, Rd, Rg1, Rg3, Rh1, Rh2, Rh3 and Rp1 have been reported to have anti-inflammatory properties in different studies related to inflammation. Ginsenosides inhibit different inducers-activated signaling protein kinases and transcription factor nuclear factor-kappaB leading to decreases in the production of cytokines and mediators of inflammation. The therapeutic potential of ginseng on TNF-α-mediated inflammatory diseases is also discussed. Taken together, this summary provides evidences for the anti-inflammatory effects of ginseng extracts and ginsenosides as well as the underlying mechanisms of their effects on inflammatory diseases. Full article
(This article belongs to the Collection Bioactive Compounds)
1317 KiB  
Review
Bismuth(III) Reagents in Steroid and Terpene Chemistry
by Jorge A. R. Salvador, Samuel M. Silvestre and Rui M. A. Pinto
Molecules 2011, 16(4), 2884-2913; https://doi.org/10.3390/molecules16042884 - 04 Apr 2011
Cited by 20 | Viewed by 10825
Abstract
Steroid and terpene chemistry still have a great impact on medicinal chemistry. Therefore, the development of new reactions or “greener” processes in this field is a contemporaneous issue. In this review, the use of bismuth(III) salts, as “ecofriendly” reagents/catalysts, on new chemical processes [...] Read more.
Steroid and terpene chemistry still have a great impact on medicinal chemistry. Therefore, the development of new reactions or “greener” processes in this field is a contemporaneous issue. In this review, the use of bismuth(III) salts, as “ecofriendly” reagents/catalysts, on new chemical processes involving steroids and terpenes as substrates will be focused. Special attention will be given to some mechanistic considerations concerning selected reactions. Full article
(This article belongs to the Special Issue Organobismuth Chemistry)
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395 KiB  
Review
Lambda-Display: A Powerful Tool for Antigen Discovery
by Elisa Beghetto and Nicola Gargano
Molecules 2011, 16(4), 3089-3105; https://doi.org/10.3390/molecules16043089 - 13 Apr 2011
Cited by 39 | Viewed by 10289
Abstract
Since its introduction in 1985, phage display technology has been successfully used in projects aimed at deciphering biological processes and isolating molecules of practical value in several applications. Bacteriophage lambda, representing a classical molecular cloning and expression system has also been exploited for [...] Read more.
Since its introduction in 1985, phage display technology has been successfully used in projects aimed at deciphering biological processes and isolating molecules of practical value in several applications. Bacteriophage lambda, representing a classical molecular cloning and expression system has also been exploited for generating large combinatorial libraries of small peptides and protein domains exposed on its capsid. More recently, lambda display has been consistently and successfully employed for domain mapping, antigen discovery and protein interaction studies or, more generally, in functional genomics. We show here the results obtained by the use of large libraries of cDNA and genomic DNA for the molecular dissection of the human B-cell response against complex pathogens, including protozoan parasites, bacteria and viruses. Moreover, by reviewing the experimental work performed in recent investigations we illustrate the potential of lambda display in the diagnostics field and for identifying antigens useful as targets for vaccine development. Full article
(This article belongs to the Special Issue Phage Display of Combinatorial Libraries)
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308 KiB  
Review
Selenol Protecting Groups in Organic Chemistry: Special Emphasis on Selenocysteine Se-Protection in Solid Phase Peptide Synthesis
by Stevenson Flemer Jr.
Molecules 2011, 16(4), 3232-3251; https://doi.org/10.3390/molecules16043232 - 18 Apr 2011
Cited by 34 | Viewed by 11964
Abstract
The appearance of selenium in organic synthesis is relatively rare, and thus examples in the literature pertaining to the masking of its considerable reactivity are similarly uncommon. Greene's Protecting Groups in Organic Synthesis, the standard reference for the state of the art in [...] Read more.
The appearance of selenium in organic synthesis is relatively rare, and thus examples in the literature pertaining to the masking of its considerable reactivity are similarly uncommon. Greene's Protecting Groups in Organic Synthesis, the standard reference for the state of the art in this arena, offers no entries for selenium protective methodology, in stark comparison to its mention of the great variety of protecting groups germane to its chalcogen cousin sulfur. This scarcity of Se-protection methods makes it no less interesting and pertinent toward the construction of selenium-containing organic systems which do indeed require the iterative blocking and de-blocking of selenol functionalities. A selenium-containing system which is especially relevant is selenocysteine, as its use in Solid Phase Peptide Synthesis requires extensive protection of its selenol side chain. This review will attempt to summarize the current state of understanding with regard to selenium protection protocol in organic synthesis. Moreover, it will provide a special emphasis on selenocysteine side chain protection, comprising both the breadth of functionality used for this purpose as well as methods of deprotection. Full article
(This article belongs to the Special Issue Protecting Group in Organic Synthesis)
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688 KiB  
Review
From Polymer to Small Organic Molecules: A Tight Relationship between Radical Chemistry and Solid-Phase Organic Synthesis
by Danilo Mirizzi and Maurizio Pulici
Molecules 2011, 16(4), 3252-3314; https://doi.org/10.3390/molecules16043252 - 18 Apr 2011
Cited by 15 | Viewed by 9222
Abstract
Since Gomberg’s discovery of radicals as chemical entities, the interest around them has increased through the years. Nowadays, radical chemistry is used in the synthesis of 75% of all polymers, inevitably establishing a close relationship with Solid-Phase Organic Synthesis. More recently, the interest [...] Read more.
Since Gomberg’s discovery of radicals as chemical entities, the interest around them has increased through the years. Nowadays, radical chemistry is used in the synthesis of 75% of all polymers, inevitably establishing a close relationship with Solid-Phase Organic Synthesis. More recently, the interest of organic chemists has shifted towards the application of usual “in-solution” radical chemistry to the solid-phase, ranging from the use of supported reagents for radical reactions, to the development of methodologies for the synthesis of small molecules or potential libraries. The aim of this review is to put in perspective radical chemistry, moving it away from its origin as a synthetic means for solid supports, to becoming a useful tool for the synthesis of small molecules. Full article
(This article belongs to the Special Issue Diversity Oriented Synthesis)
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1267 KiB  
Review
Two-Photon Polarization Dependent Spectroscopy in Chirality: A Novel Experimental-Theoretical Approach to Study Optically Active Systems
by Florencio E. Hernández and Antonio Rizzo
Molecules 2011, 16(4), 3315-3337; https://doi.org/10.3390/molecules16043315 - 18 Apr 2011
Cited by 23 | Viewed by 11423
Abstract
Many phenomena, including life itself and its biochemical foundations are fundamentally rooted in chirality. Combinatorial methodologies for catalyst discovery and optimization remain an invaluable tool for gaining access to enantiomerically pure compounds in the development of pharmaceuticals, agrochemicals, and flavors. Some exotic metamaterials [...] Read more.
Many phenomena, including life itself and its biochemical foundations are fundamentally rooted in chirality. Combinatorial methodologies for catalyst discovery and optimization remain an invaluable tool for gaining access to enantiomerically pure compounds in the development of pharmaceuticals, agrochemicals, and flavors. Some exotic metamaterials exhibiting negative refractive index at optical frequencies are based on chiral structures. Chiroptical activity is commonly quantified in terms of circular dichroism (CD) and optical rotatory dispersion (ORD). However, the linear nature of these effects limits their application in the far and near-UV region in highly absorbing and scattering biological systems. In order to surmount this barrier, in recent years we made important advancements on a novel non linear, low-scatter, long-wavelength CD approach called two-photon absorption circular dichroism (TPACD). Herein we present a descriptive analysis of the optics principles behind the experimental measurement of TPACD, i.e., the double L-scan technique, and its significance using pulsed lasers. We also make an instructive examination and discuss the reliability of our theoretical-computational approach, which uses modern analytical response theory, within a Time-Dependent Density Functional Theory (TD-DFT) approach. In order to illustrate the potential of this novel spectroscopic tool, we first present the experimental and theoretical results obtained in C2-symmetric, axially chiral R-(+)-1,1'-bi(2-naphthol), R-BINOL, a molecule studied at the beginning of our investigation in this field. Next, we reveal some preliminary results obtained for (R)-3,3′-diphenyl-2,2′-bi-1-naphthol, R-VANOL, and (R)-2,2′-diphenyl-3,3′-(4-biphenanthrol), R-VAPOL. This family of optically active compounds has been proven to be a suitable model for the structure-property relationship study of TPACD, because its members are highly conjugated yet photo-stable, and easily derivatized at the 5- and 6-positions. With the publication of these outcomes we hope to motivate more members of the scientist community to engage in state-of-the-art TPACD spectroscopy. Full article
(This article belongs to the Special Issue Chiroptical Techniques)
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