Molecules

15 pages, 4627 KiB

Open AccessArticle

Enhanced Photocatalytic Performance under Ultraviolet and Visible Light Illumination of ZnO Thin Films Prepared by Modified Sol-Gel Method

by Radka Gegova-Dzhurkova, Diana Nesheva, Irina Stambolova, Katerina Zaharieva, Valeri Dzhurkov and Ilko Miloushev

Molecules 2024, 29(17), 4005; https://doi.org/10.3390/molecules29174005 (registering DOI) - 24 Aug 2024

Abstract

Semiconductor oxides are frequently used as active photocatalysts for the degradation of organic agents in water polluted by domestic industry. In this study, sol-gel ZnO thin films with a grain size in the range of 7.5–15.7 nm were prepared by applying a novel [...] Read more.

Semiconductor oxides are frequently used as active photocatalysts for the degradation of organic agents in water polluted by domestic industry. In this study, sol-gel ZnO thin films with a grain size in the range of 7.5–15.7 nm were prepared by applying a novel two-step drying procedure involving hot air treatment at 90–95 °C followed by conventional furnace drying at 140 °C. For comparison, layers were made by standard furnace drying. The effect of hot air treatment on the film surface morphology, transparency, and photocatalytic behavior during the degradation of Malachite Green azo dye in water under ultraviolet or visible light illumination is explored. The films treated with hot air demonstrate significantly better photocatalytic activity under ultraviolet irradiation than the furnace-dried films, which is comparable with the activity of unmodified ZnO nanocrystal powders. The achieved percentage of degradation is 78–82% under ultraviolet illumination and 85–90% under visible light illumination. Multiple usages of the hot air-treated films (up to six photocatalytic cycles) are demonstrated, indicating improved photo-corrosion resistance. The observed high photocatalytic activity and good photo-corrosion stability are related to the hot air treatment, which causes a reduction of oxygen vacancies and other defects and the formation of interstitial oxygen and/or zinc vacancies in the films. Full article

(This article belongs to the Special Issue Advances in Composite Photocatalysts)

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13 pages, 775 KiB

Open AccessArticle

Measuring the Equilibrium Spreading Pressure—A Tale of Three Amphiphiles

by Boyan Peychev, Dimitrinka Arabadzhieva, Ivan L. Minkov, Iglika M. Dimitrova, Elena Mileva, Stoyan K. Smoukov and Radomir I. Slavchov

Molecules 2024, 29(17), 4004; https://doi.org/10.3390/molecules29174004 (registering DOI) - 24 Aug 2024

Abstract

A surfactant’s equilibrium spreading pressure (ESP) is the maximum decrease in surface tension achievable at equilibrium below the Krafft point. Difficulties in measuring the ESP have been noted previously but no well-established experimental protocols to overcome them exist. We present a case study [...] Read more.

A surfactant’s equilibrium spreading pressure (ESP) is the maximum decrease in surface tension achievable at equilibrium below the Krafft point. Difficulties in measuring the ESP have been noted previously but no well-established experimental protocols to overcome them exist. We present a case study of three solid amphiphiles with different propensities to spread on the air–water interface. Starting with the partially water soluble n-dodecanol (C₁₂H₂₅OH), which spreads instantaneously. The strong Marangoni flows associated with the spreading result in the dislocating of the Wilhelmy plate or crystals attaching to it. A temporary mechanical barrier in front of the spreading crystals mitigates the flows disturbing the plate. Presaturating the subphase with the amphiphile prevents the establishment of dynamic steady states, reduces the standard error by a factor of three and causes faster equilibration. The perfluoroalkylated analog of dodecanol (11:1 fluorotelomer alcohol, C₁₁F₂₃CH₂OH) is slow spreading. With surfactant crystals on the interface, the surface pressure reaches a pre-equilibrium plateau within an hour, followed by equilibration on day-long timescales. We show that it is better to estimate the ESP by averaging the values of multiple pre-equilibrium plateaus rather than waiting for equilibrium to be established. Finally, the nonspreading amphiphile DPPC exhibits a large barrier for the mass transfer from the DPPC crystal to the aqueous surface. This was overcome by introducing a volatile, water-immiscible solvent deposited on the surface next to the crystals to facilitate the spreading process and leave behind a monolayer. Full article

(This article belongs to the Special Issue Research Progress of Surfactants)

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21 pages, 6118 KiB

Open AccessArticle

Study on Soot and NOx Formation Characteristics in Ammonia/Ethylene Laminar Co-Flow Diffusion Flame

by Shuanglong Li, Qianqian Liu, Feng Zhang, Jingyun Sun, Yang Wang and Mingyan Gu

Molecules 2024, 29(17), 4003; https://doi.org/10.3390/molecules29174003 (registering DOI) - 24 Aug 2024

Abstract

The formation of soot and NOx in ammonia/ethylene flames with varying ammonia ratios was investigated through experimental and numerical analysis. The spatial distribution of the soot volume fraction and NOx concentrations along the flame central line were measured, and the mechanism of soot [...] Read more.

The formation of soot and NOx in ammonia/ethylene flames with varying ammonia ratios was investigated through experimental and numerical analysis. The spatial distribution of the soot volume fraction and NOx concentrations along the flame central line were measured, and the mechanism of soot and NOx formation during ammonia/ethylene co-combustion was analyzed using CHEMKIN 17.0. The experimental results indicated that the soot volume fraction decreases with an increase in ammonia ratio, with the soot peak concentration occurring in the upper region of the flame. The distribution of NOx is complex. In the initial part of the flame, a higher concentration of NOx is generated, and the lower the ammonia ratio, the higher the concentration of NOx. As the combustion process progresses, the concentration of NOx initially decreases and then subsequently increases rapidly, with higher ammonia ratios leading to higher concentrations of NOx. The addition of ammonia results in a decrease in CH₃, C₂H₂, and C₃H₃, and an increase in CN concentration. This leads to a transformation of carbon atoms within the combustion system, reducing the available carbon for soot formation and suppressing its generation. A higher ammonia ratio increases the likelihood that NH₃ will be oxidized to N₂, as well as increasing the probability that any generated NO will undergo reduction to N₂ through the action of the free radicals NH₂ and NH. Full article

(This article belongs to the Section Applied Chemistry)

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15 pages, 1446 KiB

Open AccessArticle

Efficient Hydroxyapatite Extraction from Salmon Bone Waste: An Improved Lab-Scaled Physico-Chemico-Biological Process

by Francisco Muñoz, Ziyad S. Haidar, Andreu Puigdollers, Ignacio Guerra, María Cristina Padilla, Nicole Ortega, Mercedes Balcells and María José García

Molecules 2024, 29(17), 4002; https://doi.org/10.3390/molecules29174002 (registering DOI) - 24 Aug 2024

Abstract

The demand for novel tissue grafting and regenerative wound care biomaterials is growing as traditional options often fall short in biocompatibility, functional integration with human tissue, associated cost(s), and sustainability. Salmon aquaculture generates significant volumes of waste, offering a sustainable opportunity for biomaterial [...] Read more.

The demand for novel tissue grafting and regenerative wound care biomaterials is growing as traditional options often fall short in biocompatibility, functional integration with human tissue, associated cost(s), and sustainability. Salmon aquaculture generates significant volumes of waste, offering a sustainable opportunity for biomaterial production, particularly in osteo-conduction/-induction, and de novo clinical/surgical bone regeneration. Henceforth, this study explores re-purposing salmon waste through a standardized pre-treatment process that minimizes the biological waste content, followed by a treatment stage to remove proteins, lipids, and other compounds, resulting in a mineral-rich substrate. Herein, we examined various methods—alkaline hydrolysis, calcination, and NaOH hydrolysis—to better identify and determine the most efficient and effective process for producing bio-functional nano-sized hydroxyapatite. Through comprehensive chemical, physical, and biological assessments, including Raman spectroscopy and X-ray diffraction, we also optimized the extraction process. Our modified and innovative alkaline hydrolysis–calcination method yielded salmon-derived hydroxyapatite with a highly crystalline structure, an optimal Ca/P ratio, and excellent biocompatibility. The attractive nano-scale cellular/tissular properties and favorable molecular characteristics, particularly well-suited for bone repair, are comparable to or even surpass those of synthetic, human, bovine, and porcine hydroxyapatite, positioning it as a promising candidate for use in tissue engineering, wound healing, and regenerative medicine indications. Full article

(This article belongs to the Topic Injectable Hydrogels for Cell and Drug Delivery)

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11 pages, 2377 KiB

Open AccessArticle

Aggression to Biomembranes by Hydrophobic Tail Chains under the Stimulus of Reductant

by Sijia Wang, Huifang Xu, Yuanyuan Li, Lingyi Zhang and Shouhong Xu

Molecules 2024, 29(17), 4001; https://doi.org/10.3390/molecules29174001 (registering DOI) - 24 Aug 2024

Abstract

Stimulus-responsive materials hold significant promise for antitumor applications due to their variable structures and physical properties. In this paper, a series of peptides with a responsive viologen derivative, Pep-C_nV (n = 1, 2, 3) were designed and synthesized. The process [...] Read more.

Stimulus-responsive materials hold significant promise for antitumor applications due to their variable structures and physical properties. In this paper, a series of peptides with a responsive viologen derivative, Pep-C_nV (n = 1, 2, 3) were designed and synthesized. The process and mechanism of the interaction were studied and discussed. An ultraviolet–visible (UV) spectrophotometer and fluorescence spectrophotometer were used to study their redox responsiveness. Additionally, their secondary structures were measured by Circular Dichroism (CD) in the presence or absence of the reductant, Na₂SO₃. DPPC and DPPG liposomes were prepared to mimic normal and tumor cell membranes. The interaction between Pep-C_nV and biomembranes was investigated by the measurements of surface tension and cargo leakage. Results proved Pep-C_nV was more likely to interact with the DPPG liposome and destroy its biomembrane under the stimulus of the reductant. And the destruction increased with the length of the hydrophobic tail chain. Pep-C_nV showed its potential as an intelligent antitumor agent. Full article

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14 pages, 4480 KiB

Open AccessArticle

Nacre-like Anisotropic Multifunctional Aramid Nanofiber Composites for Electromagnetic Interference Shielding, Thermal Management, and Strain Sensing

by Jin Dong, Jing Lin, Hebai Zhang, Jun Wang, Ye Li, Kelin Pan, Haichen Zhang and Dechao Hu

Molecules 2024, 29(17), 4000; https://doi.org/10.3390/molecules29174000 - 23 Aug 2024

Abstract

Developing multifunctional flexible composites with high-performance electromagnetic interference (EMI) shielding, thermal management, and sensing capacity is urgently required but challenging for next-generation smart electronic devices. Herein, novel nacre-like aramid nanofibers (ANFs)-based composite films with an anisotropic layered microstructure were prepared via vacuum-assisted filtration [...] Read more.

Developing multifunctional flexible composites with high-performance electromagnetic interference (EMI) shielding, thermal management, and sensing capacity is urgently required but challenging for next-generation smart electronic devices. Herein, novel nacre-like aramid nanofibers (ANFs)-based composite films with an anisotropic layered microstructure were prepared via vacuum-assisted filtration and hot-pressing. The formed 3D conductive skeleton enabled fast electron and phonon transport pathways in the composite films. As a result, the composite films showed a high electrical conductivity of 71.53 S/cm and an outstanding thermal conductivity of 6.4 W/m·K when the mass ratio of ANFs to MXene/AgNWs was 10:8. The excellent electrical properties and multi-layered structure endowed the composite films with superior EMI shielding performance and remarkable Joule heating performance, with a surface temperature of 78.3 °C at a voltage of 2.5 V. Additionally, it was found that the composite films also exhibited excellent mechanical properties and outstanding flame resistance. Moreover, the composite films could be further designed as strain sensors, which show great promise in monitoring real-time signals for human motion. These satisfactory results may open up a new opportunity for EMI shielding, thermal management, and sensing applications in wearable electronic devices. Full article

(This article belongs to the Special Issue Recent Advances in Functional Composite Materials)

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14 pages, 2746 KiB

Open AccessArticle

Theoretical Study on Vibrationally Resolved Electronic Spectra of Chiral Nanographenes

by Yijian Ma, Xian Feng, Wenxiong Yu and Chengshuo Shen

Molecules 2024, 29(17), 3999; https://doi.org/10.3390/molecules29173999 - 23 Aug 2024

Abstract

Nanographenes are of increasing importance owing to their potential applications in the photoelectronic field. Meanwhile, recent studies have primarily focused on the pure electronic spectra of nanographenes, which have been found to be inadequate for describing the experimental spectra that contain vibronic progressions. [...] Read more.

Nanographenes are of increasing importance owing to their potential applications in the photoelectronic field. Meanwhile, recent studies have primarily focused on the pure electronic spectra of nanographenes, which have been found to be inadequate for describing the experimental spectra that contain vibronic progressions. In this study, we focused on the vibronic effect on the electronic transition of a range of chiral nanographenes, especially in the low-energy regions with distinct vibronic progressions, using theoretical calculations. All the calculations were performed at the PBE0-D3(BJ)/def2-TZVP level of theory, adopting both time-dependent and time-independent approaches with Franck–Condon approximation. The resulting calculated curves exhibited good alignment with the experimental data. Notably, for the nanographenes incorporating helicene units, owing to the increasing π-extension, the major vibronic modes in the vibrationally resolved spectra differed significantly from those of the primitive helicenes. This investigation suggests that calculations that account for the vibronic effect could have better reproducibility compared with calculations based solely on pure electronic transitions. We anticipate that this study could pave the way for further investigations into optical and chiroptical properties, with a deeper understanding of the vibronic effect, thereby providing theoretical explanations with higher precision on more sophisticated nanographenes. Full article

12 pages, 1187 KiB

Open AccessArticle

Combined Liposome–Gold Nanoparticles from Honey: The Catalytic Effect of Cassyopea^® Gold on the Thermal Isomerization of a Resonance-Activated Azobenzene

by Guido Angelini and Carla Gasbarri

Molecules 2024, 29(17), 3998; https://doi.org/10.3390/molecules29173998 - 23 Aug 2024

Abstract

Gold nanoparticles (AuNPs) have been synthesized directly inside liposomes using honey as a reducing agent. The obtained aggregates, named Cassyopea^® Gold due to the method used for their preparation, show remarkable properties as reactors and carriers of the investigated AuNPs. A mean [...] Read more.

Gold nanoparticles (AuNPs) have been synthesized directly inside liposomes using honey as a reducing agent. The obtained aggregates, named Cassyopea^® Gold due to the method used for their preparation, show remarkable properties as reactors and carriers of the investigated AuNPs. A mean size of about 150 nm and negative surface charge of -46 mV were measured for Cassyopea^® Gold through dynamic light scattering and zeta potential measurements, respectively. The formation of the investigated gold nanoparticles into Cassyopea^® liposomes was spectroscopically confirmed by the presence of their typical absorption band at 516 nm. The catalytic activity of the combined liposome–AuNP nanocomposites was tested via the thermal cis–trans isomerization of resonance-activated 4-methoxyazobenzene (MeO-AB). The kinetic rate constants (k_obs) determined at 25 °C in the AuNP aqueous solution and in the Cassyopea^® Gold samples were one thousand times higher than the values obtained when performing MeO-AB cis–trans conversion in the presence of pure Cassyopea^®. The results reported herein are unprecedented and point to the high versatility of Cassyopea^® as a reactor and carrier of metal nanoparticles in chemical, biological, and technological applications. Full article

(This article belongs to the Section Nanochemistry)

18 pages, 738 KiB

Open AccessArticle

Phytochemical Characterization of Two New Olive Oil Genotypes Growing in Southern Tunisia

by Mbarka Ben Mohamed, Sihem Ben Ali, Gabriele Rocchetti, Samir Tlahig, Leila Bennani and Ferdaous Guasmi

Molecules 2024, 29(17), 3997; https://doi.org/10.3390/molecules29173997 - 23 Aug 2024

Abstract

This research can be considered as the first complete survey for the valorization of new olive genotypes cultivated in the South-East of Tunisia as well as their oils. The study aimed to characterize the phytochemical composition of virgin olive oil produced from two [...] Read more.

This research can be considered as the first complete survey for the valorization of new olive genotypes cultivated in the South-East of Tunisia as well as their oils. The study aimed to characterize the phytochemical composition of virgin olive oil produced from two olive cultivars, namely Nourgou and Gousalani. The pomological characterization of fruits, the quality criteria and the phytochemical profile were quantified. Additionally, antioxidant activity was evaluated using Ferric reducing antioxidant power (FRAP) and Oxygen radical absorbance capacity (ORAC) tests to also obtain a bioactive characterization of these monovarietal olive oils. The obtained results revealed that the analyzed olive oils samples can be classified into Extra Virgin category (EVOO) according to the regulated physicochemical characteristics. Our findings showed a significant variability in the chemical parameters of the analyzed EVOO likely associated with the genetic potential, mainly for chlorophylls contents (1.37–1.64 mg/kg), in carotenoids pigments (3.97–10.86 mg/kg), in α-tocopherol (175.59–186.87 mg/kg), in sterols (1036.4–1931.4 mg/kg) in oleic acid (65.33–68.73%), in palmitic acid (C16:0) (13.32–17.48%), in linoleic acid (C18:2) (11.06–13.47%). Additionally, the HPLC-MS/MS analysis showed that the two EVOOs analyzed contained appreciable amounts of total polyphenols, ranging from 348.03 up to 516.16 mg/kg, in Nourgou and Gousalani oils, respectively. Regarding the individual phenolic compounds, the EVOO samples were mainly characterized by phenolic alcohols, phenolic acids, secoiridoids, verbascoside, flavonoids and phenolic aldehydes. The prevalent simple phenolics detected were secoiridoids with the dominance of the oleuropein aglycone in Gousalani oil. In addition, findings from in vitro antioxidant assays (FRAP and ORAC) revealed that the two studied oils possessed a powerful antiradical activity and a good reducing power capacity. In conclusion, these new EVOOs exhibited a superior quality compared to other Tunisian varieties, considering their antiradical activity and reducing power capacity. Full article

(This article belongs to the Special Issue Chemical Analysis of Functional Foods)

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15 pages, 3018 KiB

Open AccessArticle

Methodology Approach for Microplastics Isolation from Samples Containing Sucrose

by Kornelia Kadac-Czapska, Beata Bochentyn, Aleksandra Maślarz, Sebastian Mahlik and Małgorzata Grembecka

Molecules 2024, 29(17), 3996; https://doi.org/10.3390/molecules29173996 - 23 Aug 2024

Abstract

The growing production and use of plastics significantly contribute to microplastics (MPs) contamination in the environment. Humans are exposed to MPs primarily through the gastrointestinal route, as these particles are present in beverages and food, e.g., sugar. Effective isolation and identification of MPs [...] Read more.

The growing production and use of plastics significantly contribute to microplastics (MPs) contamination in the environment. Humans are exposed to MPs primarily through the gastrointestinal route, as these particles are present in beverages and food, e.g., sugar. Effective isolation and identification of MPs from food is essential for their elimination. This study aimed to evaluate factors influencing the isolation of MPs from sucrose solutions to determine optimal conditions for the process. Polyethylene particles were used to test separation methods involving chemical digestion with acids and filtration through membrane filters made of nylon, mixed cellulose ester, and cellulose acetate with pore sizes of 0.8 and 10 µm. The effects of temperature and acid type and its concentration on plastic particles were examined using scanning electron microscopy and µ-Raman spectroscopy. The results indicate that increased temperature reduces solution viscosity and sucrose adherence to MPs’ particles, while higher acid concentrations accelerate sucrose hydrolysis. The optimal conditions for MPs’ isolation were found to be 5% HCl at 70 °C for 5 min, followed by filtration using an efficient membrane system. These conditions ensure a high recovery and fast filtration without altering MPs’ surface properties, providing a reliable basis for further analysis of MPs in food. Full article

(This article belongs to the Section Food Chemistry)

28 pages, 16270 KiB

Open AccessReview

Exploring the Dynamics of Charge Transfer in Photocatalysis: Applications of Femtosecond Transient Absorption Spectroscopy

by Na Li, Yanlong Ma and Wanjun Sun

Molecules 2024, 29(17), 3995; https://doi.org/10.3390/molecules29173995 - 23 Aug 2024

Abstract

Artificial photocatalytic energy conversion is a very interesting strategy to solve energy crises and environmental problems by directly collecting solar energy, but low photocatalytic conversion efficiency is a bottleneck that restricts the practical application of photocatalytic reactions. The key issue is that the [...] Read more.

Artificial photocatalytic energy conversion is a very interesting strategy to solve energy crises and environmental problems by directly collecting solar energy, but low photocatalytic conversion efficiency is a bottleneck that restricts the practical application of photocatalytic reactions. The key issue is that the photo-generated charge separation process spans a huge spatio-temporal scale from femtoseconds to seconds, and involves complex physical processes from microscopic atoms to macroscopic materials. Femtosecond transient absorption (fs-TA) spectroscopy is a powerful tool for studying electron transfer paths in photogenerated carrier dynamics of photocatalysts. By extracting the attenuation characteristics of the spectra, the quenching path and lifetimes of carriers can be simulated on femtosecond and picosecond time scales. This paper introduces the principle of transient absorption, typical dynamic processes and the application of femtosecond transient absorption spectroscopy in photocatalysis, and summarizes the bottlenecks faced by ultrafast spectroscopy in photocatalytic applications, as well as future research directions and solutions. This will provide inspiration for understanding the charge transfer mechanism of photocatalytic processes. Full article

(This article belongs to the Special Issue Design and Mechanisms of Photo(electro)catalysts for Water Splitting)

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Graphical abstract

20 pages, 4858 KiB

Open AccessReview

Overcoming Cancer Drug Resistance with Nanoparticle Strategies for Key Protein Inhibition

by Hyeonji Yoo, Yeonjin Kim, Jinseong Kim, Hanhee Cho and Kwangmeyung Kim

Molecules 2024, 29(17), 3994; https://doi.org/10.3390/molecules29173994 - 23 Aug 2024

Abstract

Drug resistance remains a critical barrier in cancer therapy, diminishing the effectiveness of chemotherapeutic, targeted, and immunotherapeutic agents. Overexpression of proteins such as B-cell lymphoma 2 (Bcl-2), inhibitor of apoptosis proteins (IAPs), protein kinase B (Akt), and P-glycoprotein (P-gp) in various cancers leads [...] Read more.

Drug resistance remains a critical barrier in cancer therapy, diminishing the effectiveness of chemotherapeutic, targeted, and immunotherapeutic agents. Overexpression of proteins such as B-cell lymphoma 2 (Bcl-2), inhibitor of apoptosis proteins (IAPs), protein kinase B (Akt), and P-glycoprotein (P-gp) in various cancers leads to resistance by inhibiting apoptosis, enhancing cell survival, and expelling drugs. Although several inhibitors targeting these proteins have been developed, their clinical use is often hampered by systemic toxicity, poor bioavailability, and resistance development. Nanoparticle-based drug delivery systems present a promising solution by improving drug solubility, stability, and targeted delivery. These systems leverage the Enhanced Permeation and Retention (EPR) effect to accumulate in tumor tissues, reducing off-target toxicity and increasing therapeutic efficacy. Co-encapsulation strategies involving anticancer drugs and resistance inhibitors within nanoparticles have shown potential in achieving coordinated pharmacokinetic and pharmacodynamic profiles. This review discusses the mechanisms of drug resistance, the limitations of current inhibitors, and the advantages of nanoparticle delivery systems in overcoming these challenges. By advancing these technologies, we can enhance treatment outcomes and move towards more effective cancer therapies. Full article

(This article belongs to the Special Issue Featured Reviews in Nanochemistry)

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9 pages, 918 KiB

Open AccessArticle

Differences in the Renal Accumulation of Radiogallium-Labeled (Glu)₁₄ Peptides Containing Different Optical Isomers of Glutamic Acid

by Kazuma Ogawa, Kota Nishizawa, Kenji Mishiro, Masayuki Munekane, Takeshi Fuchigami, Hiroaki Echigo, Hiroshi Wakabayashi and Seigo Kinuya

Molecules 2024, 29(17), 3993; https://doi.org/10.3390/molecules29173993 - 23 Aug 2024

Abstract

Acidic amino acid peptides have a high affinity for bone. Previously, we demonstrated that radiogallium complex-conjugated oligo-acidic amino acids possess promising properties as bone-seeking radiopharmaceuticals. Here, to elucidate the effect of stereoisomers of Glu in Glu-containing peptides [(Glu)₁₄] on their accumulation [...] Read more.

Acidic amino acid peptides have a high affinity for bone. Previously, we demonstrated that radiogallium complex-conjugated oligo-acidic amino acids possess promising properties as bone-seeking radiopharmaceuticals. Here, to elucidate the effect of stereoisomers of Glu in Glu-containing peptides [(Glu)₁₄] on their accumulation in the kidney, the biodistributions of [⁶⁷Ga]Ga-N,N′-bis-[2-hydroxy-5-(carboxyethyl)benzyl]ethylenediamine-N,N′-diacetic acid-conjugated (l-Glu)₁₄ ([⁶⁷Ga]Ga-HBED-CC-(l-Glu)₁₄), [⁶⁷Ga]Ga-HBED-CC-(d-Glu)₁₄, [⁶⁷Ga]Ga-HBED-CC-(dl-Glu)₁₄, and [⁶⁷Ga]Ga-HBED-CC-(d-Glu-l-Glu)₇ were compared. Although the accumulation of these compounds in the bone was comparable, their kidney accumulation and retention were strikingly different, with [⁶⁷Ga]Ga-HBED-CC-(d-Glu-l-Glu)₇ exhibiting the lowest level of kidney accumulation among these compounds. Repeated d- and l-peptides may be a useful method for reducing renal accumulation in some cases. Full article

(This article belongs to the Special Issue Collection of Scientific Papers by Outstanding Scientists in the Field of Bioorganic Chemistry)

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17 pages, 3711 KiB

Open AccessArticle

A Combined Computational and Experimental Approach to Studying Tropomyosin Kinase Receptor B Binders for Potential Treatment of Neurodegenerative Diseases

by Duc D. Nguyen, Shomit Mansur, Lukasz Ciesla, Nora E. Gray, Shan Zhao and Yuping Bao

Molecules 2024, 29(17), 3992; https://doi.org/10.3390/molecules29173992 - 23 Aug 2024

Abstract

Tropomyosin kinase receptor B (TrkB) has been explored as a therapeutic target for neurological and psychiatric disorders. However, the development of TrkB agonists was hindered by our poor understanding of the TrkB agonist binding location and affinity (both affect the regulation of disorder [...] Read more.

Tropomyosin kinase receptor B (TrkB) has been explored as a therapeutic target for neurological and psychiatric disorders. However, the development of TrkB agonists was hindered by our poor understanding of the TrkB agonist binding location and affinity (both affect the regulation of disorder types). This motivated us to develop a combined computational and experimental approach to study TrkB binders. First, we developed a docking method to simulate the binding affinity of TrkB and binders identified by our magnetic drug screening platform from Gotu kola extracts. The Fred Docking scores from the docking computation showed strong agreement with the experimental results. Subsequently, using this screening platform, we identified a list of compounds from the NIH clinical collection library and applied the same docking studies. From the Fred Docking scores, we selected two compounds for TrkB activation tests. Interestingly, the ability of the compounds to increase dendritic arborization in hippocampal neurons matched well with the computational results. Finally, we performed a detailed binding analysis of the top candidates and compared them with the best-characterized TrkB agonist, 7,8-dyhydroxyflavon. The screening platform directly identifies TrkB binders, and the computational approach allows for the quick selection of top candidates with potential biological activities based on the docking scores. Full article

(This article belongs to the Special Issue Featured Papers in Medicinal Chemistry II)

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17 pages, 3399 KiB

Open AccessArticle

How Doping Regulates As(III) Adsorption at TiO₂ Surfaces: A DFT + U Study

by Xiaoxiao Huang, Mengru Wu, Rongying Huang and Gang Yang

Molecules 2024, 29(17), 3991; https://doi.org/10.3390/molecules29173991 - 23 Aug 2024

Abstract

The efficient adsorption and removal of As(III), which is highly toxic, remains difficult. TiO₂ shows promise in this field, though the process needs improvement. Herein, how doping regulates As(OH)₃ adsorption over TiO₂ surfaces is comprehensively investigated by means of the [...] Read more.

The efficient adsorption and removal of As(III), which is highly toxic, remains difficult. TiO₂ shows promise in this field, though the process needs improvement. Herein, how doping regulates As(OH)₃ adsorption over TiO₂ surfaces is comprehensively investigated by means of the DFT + D3 approach. Doping creates the bidentate mononuclear (Ce doping at the Ti_5c site), tridentate (N, S doping at the O_2c site), and other new adsorption structures. The extent of structural perturbation correlates with the atomic radius when doping the Ti site (Ce >> Fe, Mn, V >> B), while it correlates with the likelihood of forming more bonds when doping the O site (N > S > F). Doping the O_2c, O_3c rather than the Ti_5c site is more effective in enhancing As(OH)₃ adsorption and also causes more structural perturbation and diversity. Similar to the scenario of pristine surfaces, the bidentate binuclear complexes with two Ti-O_As bonds are often the most preferred, except for B doping at the Ti_5c site, S doping at the O_2c site, and B doping at the O_3c site of rutile (110) and Ce, B doping at the Ti_5c site, N, S doping at the O_2c site, and N, S, B doping at the O_3c site of anatase (101). Doping significantly regulates the As(OH)₃ adsorption efficacy, and the adsorption energies reach −4.17, −4.13, and −4.67 eV for Mn doping at the Ti_5c site and N doping at the O_2c and O_3c sites of rutile (110) and −1.99, −2.29, and −2.24 eV for Ce doping at the Ti_5c site and N doping at the O_2c and O_3c sites of anatase (101), respectively. As(OH)₃ adsorption and removal are crystal-dependent and become apparently more efficient for rutile vs. anatase, whether doped at the Ti_5c, O_2c, or O_3c site. The auto-oxidation of As(III) occurs when the As centers interact directly with the TiO₂ surface, and this occurs more frequently for rutile rather than anatase. The multidentate adsorption of As(OH)₃ causes electron back-donation and As(V) re-reduction to As(IV). The regulatory effects of doping during As(III) adsorption and the critical roles played by crystal control are further unraveled at the molecular level. Significant insights are provided for As(III) pollution management via the adsorption and rational design of efficient scavengers. Full article

(This article belongs to the Special Issue Feature Papers in Computational and Theoretical Chemistry)

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17 pages, 3490 KiB

Open AccessArticle

Lupeol-3-carbamate Derivatives: Synthesis and Biological Evaluation as Potential Antitumor Agents

by Shuang Tian, Yinxu Zhao, Siqi Deng, Liman Hou, Juan Song, Ming Wang and Ming Bu

Molecules 2024, 29(17), 3990; https://doi.org/10.3390/molecules29173990 - 23 Aug 2024

Abstract

In the following study, a series of new lupeol-3-carbamate derivatives were synthesized, and the structures of all the newly derived compounds were characterized. The new compounds were screened to determine their anti-proliferative activity against human lung cancer cell line A549, human liver cancer [...] Read more.

In the following study, a series of new lupeol-3-carbamate derivatives were synthesized, and the structures of all the newly derived compounds were characterized. The new compounds were screened to determine their anti-proliferative activity against human lung cancer cell line A549, human liver cancer cell line HepG2, and human breast cancer cell line MCF-7. Most of the compounds were found to show better anti-proliferative activity in vitro than lupeol. Among them, obvious anti-proliferation activity (IC₅₀ = 5.39~9.43 μM) was exhibited by compound 3i against all three tumor cell lines. In addition, a salt reaction was performed on compound 3k (IC₅₀ = 13.98 μM) and it was observed that the anti-proliferative activity and water solubility of compound 3k·CH₃I (IC₅₀ = 3.13 μM), were significantly enhanced subsequent to the salt formation process. The preliminary mechanistic studies demonstrated that apoptosis in HepG2 cells was induced by compound 3k·CH₃I through the inhibition of the PI3K/AKT/mTOR pathway. In conclusion, a series of new lupeol-3-carbamate derivatives were synthesized via the structural modification of the C-3 site of lupeol, thus laying a theoretical foundation for the design of this new anticancer drug. Full article

(This article belongs to the Special Issue Natural Products: Isolation, Analysis and Biological Activity, 2nd Edition)

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19 pages, 2021 KiB

Open AccessArticle

Quality Assessment of Reconstructed Cow, Camel and Mare Milk Powders by Near-Infrared Spectroscopy and Chemometrics

by Mariem Majadi, Annamária Barkó, Adrienn Varga-Tóth, Zhulduz Suleimenova Maukenovna, Dossimova Zhanna Batirkhanovna, Senkebayeva Dilora, Matyas Lukacs, Timea Kaszab, Zsuzsanna Mednyánszky and Zoltan Kovacs

Molecules 2024, 29(17), 3989; https://doi.org/10.3390/molecules29173989 - 23 Aug 2024

Abstract

Milk powders are becoming a major attraction for many industrial applications due to their nutritional and functional properties. Different types of powdered milk, each with their own distinct chemical compositions, can have different functionalities. Consequently, the development of rapid monitoring methods is becoming [...] Read more.

Milk powders are becoming a major attraction for many industrial applications due to their nutritional and functional properties. Different types of powdered milk, each with their own distinct chemical compositions, can have different functionalities. Consequently, the development of rapid monitoring methods is becoming an urgent task to explore and expand their applicability. Lately, there is growing emphasis on the potential of near-infrared spectroscopy (NIRS) as a rapid technique for the quality assessment of dairy products. In the present work, we explored the potential of NIRS coupled with chemometrics for the prediction of the main functional and chemical properties of three types of milk powders, as well as their important processing parameters. Mare, camel and cow milk powders were prepared at different concentrations (5%, 10% and 12%) and temperatures (25 °C, 40 °C and 65 °C), and then their main physicochemical attributes and NIRS spectra were analyzed. Overall, high accuracy in both recognition and prediction based on type, concentration and temperature was achieved by NIRS-based models, and the quantification of quality attributes (pH, viscosity, dry matter content, fat content, conductivity and individual amino acid content) also resulted in high accuracy in the models. R²CV and R²pr values ranging from 0.8 to 0.99 and 0.7 to 0.98, respectively, were obtained by using PLSR models. However, SVR models achieved higher R²CV and R²pr values, ranging from 0.91 to 0.99 and 0.80 to 0.99, respectively. Full article

(This article belongs to the Section Food Chemistry)

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12 pages, 4201 KiB

Open AccessArticle

Enhancing the Performance of MoS₂ Field-Effect Transistors Using Self-Assembled Monolayers: A Promising Strategy to Alleviate Dielectric Layer Scattering and Improve Device Performance

by Li Cao, Junqing Wei, Xianggao Li, Shirong Wang and Guoxuan Qin

Molecules 2024, 29(17), 3988; https://doi.org/10.3390/molecules29173988 - 23 Aug 2024

Abstract

Field-effect transistors (FETs) based on two-dimensional molybdenum disulfide (2D-MoS₂) have great potential in electronic and optoelectronic applications, but the performances of these devices still face challenges such as scattering at the contact interface, which results in reduced mobility. In this work, [...] Read more.

Field-effect transistors (FETs) based on two-dimensional molybdenum disulfide (2D-MoS₂) have great potential in electronic and optoelectronic applications, but the performances of these devices still face challenges such as scattering at the contact interface, which results in reduced mobility. In this work, we fabricated high-performance MoS₂-FETs by inserting self-assembling monolayers (SAMs) between MoS₂ and a SiO₂ dielectric layer. The interface properties of MoS₂/SiO₂ were studied after the inductions of three different SAM structures including (perfluorophenyl)methyl phosphonic acid (PFPA), (4-aminobutyl) phosphonic acid (ABPA), and octadecylphosphonic acid (ODPA). The SiO₂/ABPA/MoS₂-FET exhibited significantly improved performances with the highest mobility of 528.7 cm² V⁻¹ s⁻¹, which is 7.5 times that of SiO₂/MoS₂-FET, and an on/off ratio of ~10⁶. Additionally, we investigated the effects of SAM molecular dipole vectors on device performances using density functional theory (DFT). Moreover, the first-principle calculations showed that ABPA SAMs reduced the frequencies of acoustic and optical phonons in the SiO₂ dielectric layer, thereby suppressing the phonon scattering to the MoS₂ channel and further improving the device’s performance. This work provided a strategy for high-performance MoS₂-FET fabrication by improving interface properties. Full article

(This article belongs to the Section Materials Chemistry)

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8 pages, 1015 KiB

Open AccessCommunication

Complex Formation of Ag⁺ and Li⁺ with Host Molecules Modeled on Intercalation of Graphite

by Yuriko Uetake and Hiroyuki Takemura

Molecules 2024, 29(17), 3987; https://doi.org/10.3390/molecules29173987 - 23 Aug 2024

Abstract

Pi-stacked and box-shaped host molecules with xanthene as the basis and pyrene as the π-plane were synthesized to verify cation–π interactions between graphene and metal cations. Since crystal structure analysis was not available, DFT calculations were performed to determine the optimized structure, and [...] Read more.

Pi-stacked and box-shaped host molecules with xanthene as the basis and pyrene as the π-plane were synthesized to verify cation–π interactions between graphene and metal cations. Since crystal structure analysis was not available, DFT calculations were performed to determine the optimized structure, and the π-planes were found to have a slipped parallel structure, with average distances of 456.2–581.0 pm for the stacked compound and 463.4–471.4 pm for the box-shaped compound. Li⁺ and Ag⁺ were chosen as acceptors for complexation with metal ions, and their interactions with the π-plane were clarified by NMR titration. Clearly, the interaction with metal ions increased when pyrene π-planes were stacked rather than the pyrene itself. In the stacked compound, the association constants of Ag⁺ and Li⁺ were similar; however, in the box-shaped host molecule, only Ag⁺ had moderate coordination ability, but the interaction with Li⁺ was very weak, comparable to the interaction with pyrene. As a result, intercalation is more likely to occur in stacked host compound 1, which has some degree of freedom in the pyrene rings, than in the box-shaped compound. Full article

(This article belongs to the Special Issue Two-Dimensional Materials: From Synthesis to Applications)

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20 pages, 6674 KiB

Open AccessArticle

The n-Butanol Extract Obtained from the Inner Bark of Tabebuia rosea (Bertol.) DC, Specioside, and Catalposide Induce Leukemia Cell Apoptosis in the Presence of Apicidin

by Nancy Yadira Guerrero-Pepinosa, Luz Angela Veloza and Juan Carlos Sepúlveda-Arias

Molecules 2024, 29(17), 3986; https://doi.org/10.3390/molecules29173986 - 23 Aug 2024

Abstract

The cell signaling pathways involved in the antiproliferative activities of T. rosea inner bark remain unexplored. This study evaluated the apoptotic effects of two iridoids from the inner bark of T. rosea and apicidin on THP-1 cells. The cytotoxic effects of the extract [...] Read more.

The cell signaling pathways involved in the antiproliferative activities of T. rosea inner bark remain unexplored. This study evaluated the apoptotic effects of two iridoids from the inner bark of T. rosea and apicidin on THP-1 cells. The cytotoxic effects of the extract and the pure compounds on THP-1 and Jurkat cells were also evaluated using the MTT assay. The apoptotic effect was determined by measuring the mitochondrial membrane potential. The expression of mRNA and MAPK kinase, Bax, and Bcl-2 proteins was detected by Western blotting and RT–qPCR, respectively. The extract and the compounds evaluated increased the percentage of apoptotic cells. Depolarization of the mitochondrial membrane was observed, and the number of cells in the G0/G1 phase increased. Catalposide and specioside significantly increased p38 protein expression, mostly in cells pretreated with apicidin. The p38 MAPK signaling pathway is at least one of the pathways by which the n-butanol extract obtained from Tabebuia rosea, catalposide, and specioside exerts its apoptotic effect on THP-1 cells, and this effect generates a response in the G0/G1 phase and subsequent cell death. In addition, there was depolarization of the mitochondrial membrane, an effect that was related to the participation of the proapoptotic protein Bax. Full article

(This article belongs to the Special Issue Research on Chemical Composition and Activity of Natural Products)

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14 pages, 1135 KiB

Open AccessArticle

Synthesis and Biological Activity of Homohypotaurine Obtained by the Enzyme-Based Conversion of Homocysteine Sulfinic Acid Using Recombinant Escherichia Coli Glutamate Decarboxylase

by Mario Fontana, Aysenur Gunaydin Akyildiz, Chiara D’Alonzo, Fabio Giovannercole, Arianna Zicchi, Antonio Francioso, Elisabetta Capuozzo and Daniela De Biase

Molecules 2024, 29(17), 3985; https://doi.org/10.3390/molecules29173985 - 23 Aug 2024

Abstract

l-Homocysteine, formed from S-adenosyl methionine following demethylation and adenosine release, accumulates when the methionine recycling pathway and other pathways become impaired, thus leading to hyperhomocysteinemia, a biomarker in cardiovascular diseases, neurological/psychiatric disorders, and cancer. The partial oxidation of the l-homocysteine thiol [...] Read more.

l-Homocysteine, formed from S-adenosyl methionine following demethylation and adenosine release, accumulates when the methionine recycling pathway and other pathways become impaired, thus leading to hyperhomocysteinemia, a biomarker in cardiovascular diseases, neurological/psychiatric disorders, and cancer. The partial oxidation of the l-homocysteine thiol group and its decarboxylation on C-alpha lead to the formation of l-homocysteinesulfinic acid (l-HCSA) and homohypotaurine (HHT), respectively. Both compounds are not readily available from commercial suppliers, which hinders the investigation of their biological activities. Herein, the chemical synthesis of l-HCSA, from l-homocystine, was the starting point for establishing the bio-based synthesis of HHT using recombinant Escherichia coli glutamate decarboxylase (EcGadB), an enzyme already successfully employed for the bio-based synthesis of GABA and its phosphinic analog. Prior to HHT synthesis, k_cat (33.92 ± 1.07) and K_M (38.24 ± 3.45 mM) kinetic constants were determined for l-HCSA on EcGadB. The results of our study show that the EcGadB-mediated synthesis of HHT can be achieved with good yields (i.e., 40% following enzymatic synthesis and column chromatography). Purified HHT was tested in vitro on primary human umbilical vein endothelial cells and rat cardiomyoblasts and compared to the fully oxidized analog, homotaurine (OT, also known as tramiprosate), in widespread pharmaceutical use. The results show that both cell lines display statistically significant recovery from the cytotoxic effects induced by H₂O₂ in the presence of HHT. Full article

(This article belongs to the Special Issue Enzymes in Biosynthesis and Biocatalysis)

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13 pages, 233 KiB

Open AccessArticle

Changes of Potent Odorants in Salted Duck Egg Yolk before and after Roasting

by Xiaofan Hao, Miao Liang, Runhu Xin and Yuping Liu

Molecules 2024, 29(17), 3984; https://doi.org/10.3390/molecules29173984 - 23 Aug 2024

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Abstract

As the second most widely consumed eggs, duck eggs are made into preserved eggs, salted duck eggs, and roasted duck eggs to extend their shelf-life. To investigate the differences in potent odorants (POs) between salted duck egg yolk (SDEY) and roasted duck egg [...] Read more.

As the second most widely consumed eggs, duck eggs are made into preserved eggs, salted duck eggs, and roasted duck eggs to extend their shelf-life. To investigate the differences in potent odorants (POs) between salted duck egg yolk (SDEY) and roasted duck egg yolk (RDEY), the volatiles in SDEY and RDEY were extracted through solvent extraction coupled with solvent-assisted flavor evaporation and were assayed with gas chromatography-mass spectrometry-olfactometry. A total of 45 volatiles were identified in two samples, 24 odor-active compounds (OACs) were screened, and more OACs were in RDEY. The flavor-dilution (FD) factors of OACs were obtained by aroma extract dilution analysis and ranged from 3 to 6561. Twenty-two OACs with FD factors ≥ 9 were quantitated, and the results indicated the concentrations of OACs in yolk increased greatly after salted duck eggs were roasted. Based on the concentrations and thresholds, odor activity values (OAVs) were determined; 17 odorants with OAVs ≥ 1 were determined as POs. Acetoin was the most PO in SDEY; there were more POs in RDEY, including 2-ethyl-3,6-dimethylpyrazine, acetoin, 2-acetyl-3-methylthiophene, dihydro-4-hydroxy-2(3H)-furanone, etc. The outcomes obtained have reference values for making better use of duck eggs in the food industry. Full article

(This article belongs to the Special Issue Selected Papers from the First Chinese (International) Flavor Science Forum and the Fourth Chinese Youth Forum on Food Flavor Science)

9 pages, 1502 KiB

Open AccessArticle

Evaluation of Saffron Quality Using Rapid Quantitative Inspection Technology with Near-Infrared Spectroscopy

by Ying Zhou, Han Zhang, Xiaohui Sheng, Rong Wang, Yao Yao, Qinglan Zhu, Ze Yi, Zhe Xu, Yi Wang, Cheng Zheng and Yu Tang

Molecules 2024, 29(17), 3983; https://doi.org/10.3390/molecules29173983 - 23 Aug 2024

Viewed by 64

Abstract

A predictive model utilizing near-infrared spectroscopy was developed to estimate the loss on drying, total contents of crocin I and crocin II, and picrocrocin content of saffron. Initially, the LD values were determined using a moisture-ash analyzer, while HPLC was employed for measuring [...] Read more.

A predictive model utilizing near-infrared spectroscopy was developed to estimate the loss on drying, total contents of crocin I and crocin II, and picrocrocin content of saffron. Initially, the LD values were determined using a moisture-ash analyzer, while HPLC was employed for measuring the total contents of crocin I, crocin II, and picrocrocin. The near-infrared spectra of 928 saffron samples were collected and preprocessed using first derivative, standard normal variable transformation, detrended correction, multivariate scattering correction, Savitzky–Golay smoothing, and mean centering methods. Leveraging the partial least squares method, regression models were constructed, with parameters optimized through a selective combination of the above six preprocessing methods. Subsequently, prediction models for loss on drying, total contents of crocin I and crocin II, and picrocrocin content were established, and the prediction accuracy of the models was verified. The correlation coefficients and root mean square error of loss on drying, total contents of crocin I and crocin II, and picrocrocin content demonstrated high accuracy, with R² values of 0.8627, 0.8851, and 0.8592 and root mean square error values of 0.0260, 0.0682, and 0.0465. This near-infrared prediction model established in the present study offers a precise and efficient means of assessing loss on drying, total contents of crocin I and crocin II, and picrocrocin content in saffron and is useful for the development of a rapid quality evaluation system. Full article

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22 pages, 1158 KiB

Open AccessArticle

Exploring the Bioactive Potential of Moroccan Lemon Grass (Cymbopogon citratus L.): Investigations on Molecular Weight Distribution and Antioxidant and Antimicrobial Potentials

by Ahmed Tazi, Sara El Moujahed, Noura Jaouad, Hamza Saghrouchni, Ibrahim Al-Ashkar, Liyun Liu and Faouzi Errachidi

Molecules 2024, 29(17), 3982; https://doi.org/10.3390/molecules29173982 - 23 Aug 2024

Viewed by 148

Abstract

Research on lemon grass (Cymbopogon citratus L.) revealed a variety of active molecules and examined their biological characteristics. However, most of these studies were conducted on wild varieties, while cultivated plants were addressed less. This study aimed to characterize the biomolecules and [...] Read more.

Research on lemon grass (Cymbopogon citratus L.) revealed a variety of active molecules and examined their biological characteristics. However, most of these studies were conducted on wild varieties, while cultivated plants were addressed less. This study aimed to characterize the biomolecules and biological activities of lemon grass growing under North African conditions in Morocco. Phenolic compound profiles of aqueous (AE), ethanol (EE), and methanol (ME) extracts and their fractions were obtained with steric exclusion chromatography on Sephadex G50 gel and identified by LC-MS/MS. Then, total polyphenols (TPC), flavonoids (TFC), and antioxidant activities (FRAP: scavenging value and TAC: Total Antioxidant Capacity) of the fraction were evaluated, as well as the antimicrobial activity. The obtained results showed that the ME contained eight major compounds (i.e., apigenine-7-O-rutinoside and myricitine-3-O-rutinoside). The AE showed the presence of five molecules (i.e., kaempferol-3-O-glucuronide), while EE showed the presence of three molecules (i.e., quercetine-3-O-rutinoside). Regarding the chemical characterization, the highest value of total phenolic content (TPC) was obtained in AE (25) (4.60 ± 0.29 mg/g), and the highest value of total flavonoid content (TFC) was obtained in ME (29) (0.7 ± 0.08 mg/g). Concerning the antioxidant activity, the highest FRAP was obtained in ME (29) (97.89%), and the highest total antioxidant capacity (TAC) was obtained in ME (29) (89.89%). Correlation between FRAP, TPC, and TFC was noted only in fractions of AE and ME. All tested extracts of C. citratus and their fractions showed a significant antimicrobial effect. The lowest minimum inhibitory concentration (MIC) was recorded for ME against E. coli. Extracts’ biological activities and their fractions were governed by their active molecules. These data are new and clarify a novel aspect of bioactive molecules in the extracts of cultivated C. citratus. Equally, throughout this research, we clarified the relationship between identified molecules and their biological properties, including antioxidant and anti-microbial activities, which is new for the study area. This study is suggested as a reference for comparative studies and other assays of other biological activities for the study plant. Full article

(This article belongs to the Section Natural Products Chemistry)

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17 pages, 11209 KiB

Open AccessArticle

Widely Targeted Metabolomics Analysis to Reveal Metabolite of Morus alba L. in Different Medicinal Parts

by Xinwei Wang, Yiyun Qian and Min Wei

Molecules 2024, 29(17), 3981; https://doi.org/10.3390/molecules29173981 - 23 Aug 2024

Viewed by 166

Abstract

Morus alba L. is a tradition medical and edible plant. It is rich in many important bioactive components. However, there is a dearth of systematic information about the components. Here, the Mori Cortex, Mori Folium, Mori Fructus, and Mori Ramulus were studied. Ultrahigh-performance [...] Read more.

Morus alba L. is a tradition medical and edible plant. It is rich in many important bioactive components. However, there is a dearth of systematic information about the components. Here, the Mori Cortex, Mori Folium, Mori Fructus, and Mori Ramulus were studied. Ultrahigh-performance liquid chromatography-mass spectrometry (UHPLC–MS) is used to study primary and secondary metabolites. Eight hundred two metabolites were identified and classified into 10 different categories in total. Correlation analysis, hierarchical clustering analysis, and principal component analysis of metabolites showed that different parts of the sample could be significantly different. In different medicinal parts, alkaloids accounted for 4.0%, 3.6%, 5.1%, and 4.5%; flavonoids accounted for 0.7%, 27.2%, 5.6%, 1.2%; terpenes accounted for 20.1%, 2.1%, 2.6%, 2.5%. Furthermore, the abundance of phenols, phenylpropanoids, and lipids metabolites sequentially accounted for 2.3–4.4%, 0.5–1.8%, and 2.4–5.3%. These results have improved our understanding of metabolites and provided a reference for research on the medicinal and edible value of Morus alba L. In addition, the study reveals the correlation between the components of Traditional Chinese medicine and the basic theory of TCM properties and reinterprets the ancient wisdom in the world’s traditional herbs through the perspective of modern science. Full article

(This article belongs to the Section Natural Products Chemistry)

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