Search Results (122)

Squalene and lanosterol are bioactive compounds with diverse physiological effects, found in relatively high concentrations in tea seed oil. Their levels are significantly influenced by cultivar and fruit maturity. As leaf-color specific tea cultivars gain popularity, parts of them tend to have a higher flower and fruit ratio than green-leaf tea cultivars. However, their fruit characteristics remain underexplored. This study investigated 15 tea cultivars with different leaf colors, analyzing phenotypic changes in seeds during maturation, and examining the variation patterns of squalene and lanosterol. The crude water content, dry kernel content, and oil content were closely related to the maturity and effectively reflected seed development. Lanosterol content showed an overall downward trend with increased maturity. Squalene content fluctuated sharply before the seeds fully matured, but gradually decreased once they were fully matured. At full maturity, leaf-color specific tea cultivars generally exhibited higher concentrations of squalene and lanosterol than those with green leaf. Full article

Background: Isoconazole nitrate (ISN), an antifungal agent that inhibits ergosterol synthesis by blocking lanosterol 14α-demethylation, is widely used to treat candidiasis, and improving its skin retention and permeability can enhance its therapeutic efficacy. Therefore, we developed an ISN nanoparticle (ISN-NP) gel by wet-bead milling in the presence of methylcellulose (MC). Methods: These ISN nanoparticles were incorporated into a carboxypolymethylene hydrogel (Carbopol). The ISN concentration was measured using HPLC, and Wistar rats and Candida albicans were used to evaluate skin absorption and antifungal activity, respectively. Results: The ISN-NP gel exhibited a particle size distribution ranging from 60 to 220 nm, with the nanoparticles remaining stable. In addition, the ISN-NP gel demonstrated superior antifungal activity against Candida albicans. The Carbopol gel maintained appropriate viscosity and physical stability, and the ISN nanoparticles were released from the gel. Compared with microparticle-based gels (ISN-MP gels), the ISN-NP gel showed significantly enhanced drug release and transdermal permeation, with 1.54- and 1.7-fold increases, respectively. Conclusions: These findings indicate that incorporating ISN nanoparticles (nanocrystalline ISN) into a Carbopol-based gel matrix provides a promising strategy to enhance the topical delivery of this poorly water-soluble antifungal drug. Overall, this nanogel system represents a valuable platform for transdermal delivery in clinical applications. Full article

Cholesterol (Chol) plays a crucial role in regulating membrane properties and biological processes such as membrane fusion, yet the molecular mechanisms underlying its function remain incompletely understood. In order to elucidate how sterol structure influences phospholipid organization relevant to membrane fusion, we compared the effects of Chol and its biosynthetic precursor lanosterol (Lan) on hydrated phosphatidylethanolamine (PE) assemblies using X-ray diffraction, the neutral flotation method, and osmotic stress measurements. Volumetric analyses revealed that Lan has a larger occupied molecular volume than Chol in the bilayers. These values were largely independent of differences between phospholipids (phosphatidylcholine and PE), indicating that sterols are deeply embedded within the bilayer. In palmitoyl-oleoyl-PE lamellar membranes, both sterols increased bilayer thickness. They both enhanced short-range repulsive hydration forces, but Chol suppressed fluctuation-induced repulsion more effectively, reflecting its greater stiffening effect. In bacterial PE systems forming the inverted hexagonal (H_II) phase, increasing sterol concentration decreased the lattice constant, with a more substantial effect for Lan, which also induced greater curvature of the water columns. These results suggest that while Chol enhances mechanical rigidity and membrane cohesion, Lan promotes molecular flexibility and curvature, properties associated with fusion intermediates. Full article

Background/Objectives: Animal and fungal sterols and stanols exhibit remarkable structural diversity, driven by variations in the number and position of C=C bonds within the steroidal tetracyclic core and side chain, along with diverse branching patterns of the latter. Similarly to phytosterols, these metabolites produce highly complex tandem mass spectra, whose interpretation has so far been limited. To address this gap, the fragmentation behavior of selected animal/fungal sterols and stanols was studied in this paper. Methods: Higher-Collisional-energy Dissociation–High-resolution tandem mass spectrometry (HCD-HRMS/MS) of protonated/dehydrated species generated via atmospheric pressure chemical ionization (APCI) was performed on structurally diverse compounds, including lathosterol, desmosterol, zymosterol, lanosterol, ergosterol, chalinasterol, and the stanols coprostanol and cholestanol. Results: Structurally diagnostic product ions originating from the side chains were unveiled, shedding light on the intramolecular migration of positive charge from the initial ionization site at C3 to alternative stable sites across the molecular structure, which is a typical mechanism also noted in cholesterol and phytosterols. In addition, characteristic fragmentation patterns related to the steroidal backbone were found and discussed for Δ⁷, Δ^5,7 and Δ⁸-sterols, and a novel elucidation of the fragmentation behavior of 4,4-dimethyl-Δ⁸-sterols, based on lanosterol as a model compound, was achieved. The relative intensities of diagnostic product ions allowed a correlation with specific structural motifs, and “cholesterol-like” and “stigmasterol-like” fragmentations pathways were recognized. These findings were integrated with prior data on cholesterol and plant sterol fragmentation acquired under identical analytical conditions. Moreover, as a proof of its relevance for novel sterol identification, MS/MS-related information was successfully applied to the identification of a positional isomer (Δ⁷) of zymosterol in baker’s yeast extract, along with typical fungal major sterols. Conclusions: The comprehensive archive of sterol/stanol fragmentations obtained by APCI-HCD-MS/MS might prove very useful for the future characterization of novel sterol/stanol species in complex matrices. Full article

Dermatophytes are highly infectious pathogenic fungi that colonize keratinized tissues like skin, hair, and nails, causing superficial infections such as tinea capitis, onychomycosis, tinea corporis, and tinea pedis in humans and animals. In immunocompromised patients, they may invade deeper tissues and organs, leading to severe or life-threatening conditions if untreated or inadequately managed. While most infections respond to topical antifungals, some require complex treatment and show resistance to standard therapies. Therefore, novel antifungal agents are needed. We investigated the antidermatophytic activity of imidazole-thiosemicarbazides against Microsporum canis, Trichophyton spp., and Chrysosporium spp. using the broth microdilution method, comparing results to ketoconazole and amphotericin B through minimal inhibitory concentration (MIC), half-maximal inhibitory concentration (IC₅₀), and selectivity index (SI). Iodine- and bromine-substituted compounds showed the strongest activity, with MICs of 15.15 (IC₅₀ < 1 μM; SI > 213) and 73.46 μg/mL (IC₅₀ < 1 μM; SI > 846) against T. tonsurans, and 3.87 (IC₅₀ = 7.21 μM; SI > 29.6) and 7.38 μg/mL (IC₅₀ = 11.06 μM; SI = 76.6) against M. canis. In silico analysis revealed interactions with α-keratin and lanosterol-14-α demethylase (the azole target enzyme), suggesting enhanced drug retention and action. These findings support these compounds as promising leads for further antifungal development. Full article

The worldwide increase in antifungal resistance, particularly in Candida sp., requires the exploration of novel therapeutic agents. Natural compounds have been a rich source of antimicrobial molecules, where peptides constitute the class of the most bioactive components. Therefore, this study looks into the target-specific binding efficacy of insect-derived antifungal peptides (n = 37) as possible alternatives to traditional antifungal treatments. Using computational methods, namely the HPEPDOCK and HDOCK platforms, molecular docking was performed to evaluate the interactions between selected key fungal targets, lanosterol 14-demethylase, or LDM (PDB ID: 5V5Z), secreted aspartic proteinase-5, or Sap-5 (PDB ID: 2QZX), N-myristoyl transferase, or NMT (PDB ID: 1NMT), and dihydrofolate reductase, or DHFR, of C. albicans. The three-dimensional peptide structure was modelled through the PEP-FOLD 3.5 tool. Further, we predicted the physicochemical properties of these peptides through the ProtParam and PEPTIDE 2.0 tools to assess their drug-likeness and potential for therapeutic applications. In silico results show that Blap-6 from Blaps rhynchopeter and Gomesin from Acanthoscurria gomesiana have the most antifungal potential against all four targeted proteins in Candida sp. Additionally, a molecular dynamics simulation study of LDM-Blap-6 was carried out at 100 nanoseconds. The overall predictions showed that both have strong binding abilities and are good candidates for drug development. In in vitro studies, Gomesin achieved complete biofilm eradication in three out of four Candida species, while Blap-6 showed moderate but consistent reduction across all species. C. tropicalis demonstrated relative resistance to complete eradication by both peptides. The present study provides evidence to support the antifungal activity of certain insect peptides, with potential to be used as alternative drugs or as a template for a new synthetic or modified peptide in pursuit of effective therapies against Candida spp. Full article

Background: Exposure to per- and polyfluoroalkyl substances (PFAS, including 7H-Perfluoro-4-methyl-3,6-dioxaoctanesulfonic acid (PFESA-BP2), perfluorooctanoic acid (PFOA), and hexafluoropropylene oxide (GenX), has been associated with liver dysfunction. While previous research has characterized PFAS-induced hepatic lipid alterations, their downstream effects on energy metabolism remain unclear. This study investigates metabolic alterations in the liver following PFAS exposure to identify mechanisms leading to hepatoxicity. Methods: We analyzed RNA sequencing datasets of mouse liver tissues exposed to PFAS to identify metabolic pathways influenced by the chemical toxicant. We integrated the transcriptome data with a mouse genome-scale metabolic model to perform in silico flux analysis and investigated reactions and genes associated with lipid and energy metabolism. Results: PFESA-BP2 exposure caused dose- and sex-dependent changes, including upregulation of fatty acid metabolism, β-oxidation, and cholesterol biosynthesis. On the contrary, triglycerides, sphingolipids, and glycerophospholipids metabolism were suppressed. Simulations from the integrated genome-scale metabolic models confirmed increased flux for mevalonate and lanosterol metabolism, supporting potential cholesterol accumulation. GenX and PFOA triggered strong PPARα-dependent responses, especially in β-oxidation and lipolysis, which were attenuated in PPARα^−/− mice. Mitochondrial fatty acid transport and acylcarnitine turnover were also disrupted, suggesting impaired mitochondrial dysfunction. Additional PFAS effects included perturbations in the tricarboxylic acid (TCA) cycle, oxidative phosphorylation, and blood–brain barrier (BBB) function, pointing to broader systemic toxicity. Conclusions: Our findings highlight key metabolic signatures and suggest PFAS-mediated disruption of hepatic and possibly neurological functions. This study underscores the utility of genome-scale metabolic modeling as a powerful tool to interpret transcriptomic data and predict systemic metabolic outcomes of toxicant exposure. Full article

Sideroxylon cinereum, an endemic Mauritian fruit, was investigated through comprehensive chemical analyses of solvent extracts from its pulp and seed. Dried fruit materials were subjected to maceration using water and organic solvents including methanol, ethanol, propanol, and acetone to obtain extracts of varying polarity. Preliminary phytochemical screening revealed the presence of several bioactive compounds, with pulp extracts generally richer in phytochemicals than seed extracts. UV-Vis and FTIR analyses confirmed key organic constituents, including sulfoxides in seeds. HPLC quantification showed notable citric acid content in the pulp (15.63 mg/g dry weight). Antioxidant assays indicated that organic solvent extracts of the pulp had superior free radical scavenging activity, while the seed’s aqueous extract exhibited the highest ferric reducing power. GC–MS profiling identified a diverse bioactive profile rich in terpenes, notably lanosterol acetate (>45% in both pulp and seeds). It is important to note that these findings are based on solvent extracts, which may differ from the phytochemical composition of the whole fruit as typically consumed. Among the extracts, aqueous fractions are likely the most relevant to dietary intake. Overall, the extracts of Sideroxylon cinereum pulp and seed show potential as sources of bioactive compounds for functional product development. Full article

Cataract formation remains a significant cause of global visual impairment. Increasing attention has been directed toward antioxidant-based interventions as potential non-surgical strategies to delay or prevent cataractogenesis, particularly in the age-related and diabetic contexts. This review summarizes recent preclinical evidence on nutritional antioxidants for the prevention of age-related and diabetic cataracts. Agents such as trimetazidine, Moringa oleifera stem extract, ginsenoside Rg1, lanosterol nanoparticles, β-casomorphin-7, and cerium oxide-based nanotherapies have been shown to mitigate oxidative damage, modulate redox signaling pathways, and preserve lens clarity. Advances in drug delivery, including topical formulations, nanoparticle carriers, and intravitreal injections, have been proposed to overcome the anatomical and pharmacokinetic barriers associated with the avascular lens. The new data support ongoing translational research to maximize the clinical use of antioxidants and highlight their therapeutic potential in the prevention of age-related and diabetic cataracts. Full article

Smith–Lemli–Opitz syndrome (SLOS) is a developmental disability arising from bi-allelic pathogenic variants in the 7-dehydrocholestrol reductase (DHCR7) enzyme and the accumulation of 7-dehydrocholesterol (7-DHC). 7-DHC spontaneously oxidizes and gives rise to cytotoxic oxysterols. Our recent high-throughput screening on Dhcr7-deficient Neuro2a cells identified hydroxyzine (HYZ) as a medication that could counteract the high levels of 7-DHC. We assessed the effects of HYZ in Dhcr7-deficient Neuro2a cells, neuronal cultures and glial cultures from Dhcr7^T93M/T93M transgenic mice, and human dermal fibroblasts from patients with SLOS. LC-MS/MS biochemical analyses revealed a strong modulatory effect of HYZ on post-lanosterol biosynthesis across all four SLOS models. However, the HYZ-induced biochemical changes were complex, dose-dependent, and variable across the four SLOS models. Dhcr7-deficient Neuro2a cells showed decreased 7-DHC, 8-dehydrocholesterol (8-DHC), and desmosterol (DES) levels (all p < 0.01), while neuronal and glial cultures from Dhcr7^T93M/T93M transgenic mice reported 8 significantly altered analytes (all p < 0.001). Human dermal fibroblast from patients with SLOS reacted to HYZ exposure with significantly decreased 7-DHC, 7-dehydrodesmosterol (7-DHD), and dihydrolanosterol (DHL) levels (p < 0.001), coupled with elevation in zymosterol (ZYM), zymostenol (ZYME), and 8-DHC (p < 0.001). Further evaluations are required to determine if the potentially beneficial effects of decreased 7-DHC, 7-DHD and DHL levels in SLOS models and patient biomaterials are counteracted by the rise in other post-lanosterol intermediates. Full article

The thiazole heterocycle is one of the most common moieties found in various drugs. Using 2-aminothiazole as the core structure, the amino group was functionalized with an amide. As a result, 30 trisubstituted 2-amino-4, 5-diarylthiazole derivatives were synthesized, with different substitutions introduced at the C2, C4, and C5 positions. The anti-Candida albicans biological activities of these synthetic compounds on five kinds of Candida albicans at different concentrations were detected by the microdilution method. In the first round, four derivatives of 2-amino-4, 5-diarylthiazole exhibited moderate anti-Candida albicans activity. Among them, 4a8 was chosen to be subjected to a demethylation process. Thus, 5a8 was synthesized successfully, giving anti-Candida albicans activity (MIC₈₀ = 9 μM) similar to that of a typical antifungal drug, fluconazole. To understand the mechanism of anti-Candida albicans, molecular docking of the most active 5a8 against four target proteins of anti-Candida albicans, such as glutamine-fructose-6-phosphoamidamitransferase (GFAT), protein kinase (Yck2), heat-shock protein 90 (Hsp90), and lanosterol 14a-demethylase (CYP51) was carried out. Our research will provide an experimental basis and theoretical guidance for the further design of a new aminothiazole-leading pharmaceutical molecule. Full article

This publication reports the controlled cultivation of Zanthoxylum chiloperone var. angustifolium Engl. (Rutaceae) in several growth substrates under controlled greenhouse conditions. This plant is well-known for its anti-Chagas (trypanocidal) activity, related to the presence of several β-carboline alkaloids. The metabolomic study of Z. chiloperone seedlings over two years of growth (2018–2020) was performed using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOFMS). The canthin-6-one alkaloids, canthin-6-one and 5-methoxy-canthin-6-one, were putatively identified in Z. chiloperone extracts. Finally, in vitro and in silico studies of trypanocidal activity were performed, suggesting that canthin-6-one alkaloids could interact with the main pharmacological targets against Trypanosoma cruzi, cruzain protease, dihydroorotate dehydrogenase, lanosterol 14-alpha-demethylase, farnesyl diphosphate, and squalene synthases. Full article

Aspergillus fumigatus is intrinsically resistant to the widely used antifungal fluconazole, and therapeutic failure can result from acquired resistance to voriconazole, the primary treatment for invasive aspergillosis. The molecular basis of substrate specificity and innate and acquired resistance of A. fumigatus to azole drugs were addressed using crystal structures, molecular models, and expression in Saccharomyces cerevisiae of the sterol 14α-demethylase isoforms AfCYP51A and AfCYP51B targeted by azole drugs, together with their cognate reductase AfCPRA2 and AfERG6 (sterol 24-C-methyltransferase). As predicted by molecular modelling, functional expression of CYP51A and B required eburicol and not lanosterol. A crowded conformationally sensitive region involving the BC-loop, helix I, and the heme makes AfCYP51A T289 primarily responsible for resistance to fluconazole, VT-1161, and the agrochemical difenoconazole. The Y121F T289A combination was required for higher level acquired resistance to fluconazole, VT-1161, difenoconazole, and voriconazole, and confirms posaconazole, isavuconazole and possibly ravuconazole as preferred treatments for target-based azole-resistant aspergillosis due to such a combination of mutations. Full article

Nanotechnological methods for creating multifunctional fabrics are attracting global interest. The incorporation of nanoparticles in the field of textiles enables the creation of multifunctional textiles exhibiting UV irradiation protection, antimicrobial properties, self-cleaning properties and photocatalytic. Nanomaterials-loaded textiles have many innovative applications in pharmaceuticals, sports, military the textile industry etc. This study details the biosynthesis and characterization of silver nanoparticles (AgNPs) using the aqueous mycelial-free filtrate of Aspergillus flavus. The formation of AgNPs was indicated by a brown color in the extracellular filtrate and confirmed by UV-Vis spectroscopy with a peak at 426 nm. The Box-Behnken design (BBD) is used to optimize the physicochemical parameters affecting AgNPs biosynthesis. The desirability function was employed to theoretically predict the optimal conditions for the biosynthesis of AgNPs, which were subsequently experimentally validated. Through the desirability function, the optimal conditions for the maximum predicted value for the biosynthesized AgNPs (235.72 µg/mL) have been identified as follows: incubation time (58.12 h), initial pH (7.99), AgNO₃ concentration (4.84 mM/mL), and temperature (34.84 °C). Under these conditions, the highest experimental value of AgNPs biosynthesis was 247.53 µg/mL. Model validation confirmed the great accuracy of the model predictions. Scanning electron microscopy (SEM) revealed spherical AgNPs measuring 8.93–19.11 nm, which was confirmed by transmission electron microscopy (TEM). Zeta potential analysis indicated a positive surface charge (+1.69 mV), implying good stability. X-ray diffraction (XRD) confirmed the crystalline nature, while energy-dispersive X-ray spectroscopy (EDX) verified elemental silver (49.61%). FTIR findings indicate the presence of phenols, proteins, alkanes, alkenes, aliphatic and aromatic amines, and alkyl groups which play significant roles in the reduction, capping, and stabilization of AgNPs. Cotton fabrics embedded with AgNPs biosynthesized using the aqueous mycelial-free filtrate of Aspergillus flavus showed strong antimicrobial activity. The disc diffusion method revealed inhibition zones of 15, 12, and 17 mm against E. coli (Gram-negative), S. aureus (Gram-positive), and C. albicans (yeast), respectively. These fabrics have potential applications in protective clothing, packaging, and medical care. In silico modeling suggested that the predicted compound derived from AgNPs on cotton fabric could inhibit Penicillin-binding proteins (PBPs) and Lanosterol 14-alpha-demethylase (L-14α-DM), with binding energies of −4.7 and −5.2 Kcal/mol, respectively. Pharmacokinetic analysis and sensitizer prediction indicated that this compound merits further investigation. Full article

Background/Objectives: The increase in fungal infections, both systemic and invasive, is a major source of morbidity and mortality, particularly among immunocompromised people such as cancer patients and organ transplant recipients. Because of their strong therapeutic activity and excellent safety profiles, azole antifungals are currently the most extensively used systemic antifungal drugs. Antibacterial properties of various topical antifungals, such as oxiconazole, which features oxime ether functionality, were discovered, indicating an exciting prospect in antimicrobial chemotherapy. Methods: In this study, eleven new oxime ether derivatives with the azole scaffold (5a–k) were synthesized and tested for their antimicrobial effects using the microdilution method to obtain broad-spectrum hits. Results: Although the title compounds showed limited efficacy against Candida species, they proved highly effective against dermatophytes. Compounds 5c and 5h were the most potent derivatives against Trichophyton mentagrophytes and Arthroderma quadrifidum, with minimum inhibitory concentration (MIC) values lower than those of the reference drug, griseofulvin. The MIC of 5c and 5h were 0.491 μg/mL and 0.619 μg/mL against T. mentagrophytes (MIC of griseofulvin: 2.52 μg/mL). The compounds were also tested against Gram-positive and Gram-negative bacteria. Briefly, 5c was the most active against Escherichia coli and Bacillus subtilis, with MIC values much better than that of ciprofloxacin (MIC of 5c = 1.56 μg/mL and 1.23 μg/mL, MIC of ciprofloxacin = 31.49 and 125.99 μg/mL, respectively). Molecular docking suggested a good fit in the active site of fungal lanosterol 14α-demethylase (CYP51) and bacterial FtsZ (Filamenting temperature-sensitive mutant Z) protein. Conclusions: As a result, the title compounds emerged as promising entities with broad antifungal and antibacterial effects, highlighting the utility of oxime ether function in the azole scaffold. Full article