Search Results (461)

Wild Ganoderma lucidum from Nepal’s high-altitude regions was studied to identify key bioactive compounds and assess the influence of solvent type—water, ethanol, methanol, and acetone—on extraction efficiency and biological activity. Extracts were evaluated for antioxidant potential, cytotoxicity against HeLa cells, and phytochemical composition via gas chromatography–mass spectrometry (GC-MS). Solvent type significantly affected both yield and bioactivity. Acetone yielded the highest crude extract (5.01%), while ethanol extract exhibited the highest total phenolic (376.5 ± 9.3 mg PG/g) and flavonoid content (30.3 ± 0.5 mg QE/g). Methanol extract was richest in lycopene (0.07 ± 0.00 mg/g) and β-carotene (0.45 ± 0.02 mg/g). Ethanol extract demonstrated consistently strong DPPH, superoxide, hydroxyl, and nitric oxide radical scavenging activity, along with high reducing power. All extracts showed dose-dependent cytotoxicity against HeLa cells, with ethanol and water extracts showing the greatest inhibition (>65% at 1000 µg/mL). GC-MS profiling identified solvent-specific bioactive compounds including sterols, terpenoids, polyphenols, and fatty acids. Notably, pharmacologically relevant compounds such as hinokione, ferruginol, ergosterol, and geranylgeraniol were detected. These findings demonstrate the therapeutic potential of G. lucidum, underscore the importance of solvent selection, and suggest that high-altitude ecological conditions may influence its bioactive metabolite profile. Full article

Background/Objectives: The diminished efficacy of azoles in treating fungal infections is attributed to the emergence of resistance among pathogenic fungi. Employing a synergistic approach with other compounds to enhance the antifungal activity of azoles has shown promise, yet the availability of clinically valuable adjuvants for azoles and allylamines remains limited. Studies have demonstrated that the human host environment provides multiple carbon sources, which can influence the susceptibility of C. albicans to antifungal agents. Therefore, a comprehensive investigation into the mechanisms by which carbon sources modulate the susceptibility of C. albicans to azoles may uncover a novel pathway for enhancing the antifungal efficacy of azoles. Methods: This study explored the impact of various carbon sources on the antifungal efficacy of azoles through methodologies including minimum inhibitory concentration (MIC) assessments, super-MIC growth (SMG) assays, disk diffusion tests, and spot assays. Additionally, the mechanism by which galactose augments the antifungal activity of azoles was investigated using a range of experimental approaches, such as gene knockout and overexpression techniques, quantitative real-time PCR (qRT-PCR), Western blot analysis, and cycloheximide (CHX) chase experiments. Results: This study observed that galactose enhances the efficacy of azoles against C. albicans by inhibiting the translation of Erg1. This results in the suppression of Erg1 protein levels and subsequent inhibition of ergosterol biosynthesis in C. albicans. Conclusions: In C. albicans, the translation of Erg1 is inhibited when galactose is utilized as a carbon source instead of glucose. This novel discovery of galactose’s inhibitory effect on Erg1 translation is expected to enhance the antifungal efficacy of azoles. Full article

Invasive infections with rare yeasts are increasing worldwide and are associated with higher mortality rates due to their resistance to antifungal drugs. Accurate antifungal susceptibility testing (AFST) is crucial for proper management of rare yeast infections. We performed AFST of 74 Candida kefyr isolates by Etest, EUCAST-based MICRONAUT-AM assay (MCN-AM) and reference Clinical and Laboratory Standards Institute broth microdilution method (CLSI). Essential agreement (EA, ±1 two-fold dilution), categorical agreement (CA), major errors (MEs) and very-major errors (VmEs) were determined using epidemiological cut-off values of ≤1.0 µg/mL, ≤0.03 µg/mL, ≤0.5 µg/mL and ≤1 µg/mL, defining wild-type isolates for fluconazole, voriconazole, micafungin and amphotericin B (AMB), respectively. Results for AMB susceptibility were correlated with ERG2/ERG3 mutations and total-cell sterols. CA of ≥97% was recorded between any two methods while EA varied between 72 and 82%, 87 and 92%, and 49 and 76% for fluconazole, voriconazole and micafungin, respectively. For AMB, CAs between CLSI and Etest; CLSI and MCN-AM; MCN-AM and Etest were 95% (4 ME, 0 VmE), 96% (3 ME, 0 VmE) and 99%, respectively, while EA varied from 32% to 69%. Non-synonymous ERG2/ERG3 mutations and no ergosterol were found in seven of eight isolates of non-wild types for AMB by Etest. Our data show that Etest, CLSI and MCN-AM methods are suitable for AFST of C. kefyr for fluconazole, voriconazole and micafungin. Excellent CAs for AMB between Etest and MCN-AM with concordant sterol profiles but not with CLSI suggest that Etest is also an excellent alternative for the detection of C. kefyr isolates with reduced susceptibility to AMB. Full article

Cordyceps takaomontana is a medicinal fungus with significant pharmacological value, but how soil microbes promote its growth remains unclear. We established a solid-state co-culture system involving C. takaomontana synnemata and its native soil fungi of Fusarium paeoniae and Bjerkandera minispora. Both F. paeoniae and B. minispora significantly promoted synnematal growth and enhanced antioxidant enzyme activities. Total triterpenoid content increased substantially. F. paeoniae markedly elevated levels of ergosterol peroxide, whereas B. minispora boosted accumulation of L-arabinose, ergotamine, and euphol. Metabolomics revealed that both fungi activated key metabolic pathways (including ABC transporters, mineral absorption, and protein digestion/absorption). F. paeoniae uniquely upregulated phenylalanine metabolism. This work elucidates the metabolic mechanisms underlying growth promotion of C. takaomontana mediated by F. paeoniae and B. minispora as well as deciphers potential pharmacologically active metabolites. These findings provide a foundation for strategically improving artificial cultivation and developing functional microbial inoculants. Full article

Molasses, a by-product of raw sugar production, is widely used as a cost-effective carbon and nutrient source for industrial fermentations, including the production of baker’s yeast (Saccharomyces cerevisiae). Due to the cost and limited availability of molasses, efforts have been made to replace molasses with cheaper and more readily available substrates such as corn syrup. However, the quality of dry yeast drops following the replacement of molasses with corn syrup, despite the same amount of total sugar being provided. Our understanding of how molasses replacement affects yeast physiology, especially during the dehydration step, is limited. Here, we examined changes in gene expression of a strain of baker’s yeast during fermentation with increasing corn syrup to molasses ratios at the transcriptomic level. Our findings revealed that the limited availability of the key metal ions copper, iron, and zinc, as well as sulfur from corn syrup (i) reduced their intracellular storage, (ii) impaired the synthesis of unsaturated fatty acids and ergosterol, as evidenced by the decreasing proportions of these important membrane components with higher proportions of corn syrup, and (iii) inactivated oxidative stress response enzymes. Taken together, the molecular and metabolic changes observed suggest a potential reduction in nutrient reserves for fermentation and a possible compromise in cell viability during the drying process, which may ultimately impact the quality of the final dry yeast product. These findings emphasize the importance of precise nutrient supplementation when substituting molasses with cheaper substrates. Full article

The selection of plant-based substrates for mushroom cultivation is a key factor influencing their growth and metabolism. The aim of this study was to demonstrate, in an innovative approach, differences in the content of biologically active compounds, bioelements, and antioxidant properties of Hericium erinaceus (Bull.) Pers. cultivated on various plant-based substrates derived from waste materials, specifically hemp straw and beech sawdust. Another objective was to compare various extraction methods in terms of their impact on the concentration of these compounds. Elemental analysis was performed using the TXRF method, while bioactive constituents were determined using the DAD/UV RP-HPLC technique. The plant-based substrate and extraction method influenced the levels of obtained metabolites. Dual extraction with moderate ethanol concentrations was most effective for isolating key bioactive compounds from H. erinaceus—notably ergothioneine, lovastatin, L-phenylalanine, and ergosterol—while antioxidant activity did not correlate with the concentration of the solvent used. Although dual extracts enhanced certain antioxidants and metabolites, whole fruiting bodies contained higher levels of bioelements. Overall, fruiting bodies grown on beech sawdust had greater amounts of most bioactive compounds compared to those cultivated on hemp straw, emphasizing that both substrate choice and extraction method critically influence the mushroom’s bioactive profile and its potential health benefits. Full article

Azole resistance in dermatophytes, particularly Trichophyton indotineae, has become a growing global concern. Current antifungal susceptibility testing protocols (EUCAST, CLSI) have limitations in reproducibility and sensitivity. This study aimed to evaluate how medium composition, incubation temperature, and spore concentration influence itraconazole susceptibility testing across various dermatophyte species. Thirty-eight clinical isolates representing Trichophyton, Microsporum, and Epidermophyton species were tested using a microplate laser nephelometry system (MLN). IC₅₀ values for itraconazole were determined in three different media (Sabouraud glucose (SG), RPMI-based (RG), and RG supplemented with casein (RGC)) at 28 °C and 34 °C. Effects of spore concentration on growth dynamics and lag phase were also analyzed. SG medium provided clear phenotypic separation between resistant and sensitive isolates. In contrast, RG and RGC showed overlapping IC₅₀ values. Lower spore concentrations revealed underlying growth differences, which were masked at higher inoculum levels. Temperature and media composition significantly affected IC₅₀ outcomes. Genotypic analysis confirmed resistance-associated Erg11B point mutations and genomic amplifications in T. indotineae, particularly in combination with Erg1 mutations, forming distinct subpopulations. SG medium combined with reduced spore concentrations offered improved differentiation of resistant versus sensitive strains. These findings support the development of more accurate susceptibility testing protocols and highlight the need to establish species-specific ECOFF values for dermatophytes. Full article

In this study, we investigated the mitochondrial defects resulting from the deletion of GCN5, a lysine-acetyltransferase, in the yeast Saccharomyces cerevisiae. Gcn5 serves as the catalytic subunit of the SAGA acetylation complex and functions as an epigenetic regulator, primarily acetylating N-terminal lysine residues on histones H2B and H3 to modulate gene expression. The loss of GCN5 leads to mitochondrial abnormalities, including defects in mitochondrial morphology, a reduced mitochondrial DNA copy number, and defective mitochondrial inheritance due to the depolarization of actin filaments. These defects collectively trigger the activation of the mitophagy pathway. Interestingly, deleting CSN5, which encodes to Csn5/Rri1 (Csn5), the catalytic subunit of the COP9 signalosome complex, rescues the mitochondrial phenotypes observed in the gcn5Δ strain. Furthermore, these defects are suppressed by exogenous ergosterol supplementation, suggesting a link between the rescue effect mediated by CSN5 deletion and the regulatory role of Csn5 in the ergosterol biosynthetic pathway. Full article

Sclerotinia sclerotiorum, known as a typical necrotrophic pathogenic fungus, exhibits a complex pathogenic mechanism. Research on S. sclerotiorum has primarily focused on oxalic acid, pathogenicity-related enzymes, and secreted proteins. In this study, we identified a transcription factor, SsSR (S. sclerotiorum Sterol-Related transcription factor), which regulates S. sclerotiorum infection by modulating virulence through ergosterol biosynthesis. We characterized the transcriptional activity of SsSR and its downstream target gene, SsCYP51. SsSR undergoes phosphorylation induced by the host plant, subsequently regulating the expression of SsCYP51. The deletion of SsSR or SsCYP51 does not affect the growth or acid production of S. sclerotiorum, but it leads to a reduction in ergosterol, significantly diminishing virulence and impairing the stress tolerance of the hyphae. In summary, this study identifies a transcription factor, SsSR, that specifically regulates the virulence of S. sclerotiorum. SsSR upregulates the expression of SsCYP51 through phosphorylation during the infection phase, leading to the synthesis of ergosterol, which enhances hyphal stress tolerance and thereby promotes infection. Full article

The emergence of antifungal-resistant Aspergillus fumigatus (A. fumigatus) became a serious public health concern, underscoring the need for new effective antifungal agents. Here, we present a strategy based on the in situ generation of radical species that are toxic to the pathogen. The synthesis of an alkoxyamine linked to a peptide substrate recognized by A. fumigatus-secreted dipeptidyl peptidase is described. Kinetic experiments show a stable prodrug prior to enzymatic activation. Ensuing peptide cleavage and spontaneous homolysis resulted in the generation of a stable nitroxide and a reactive alkyl radical moiety. Next, the exposure of A. fumigatus spores to the prodrug lead to pathogen growth inhibition in a compound concentration-dependent fashion (e.g., 42% inhibition at 10 µg/L). Importantly, the designed alkoxyamine inhibited not only the growth of a clinical voriconazole-susceptible A. fumigatus strain, but also the growth of a strain resistant to this azole. To determine the antifungal importance of the reactive alkyl radical, its substitution with a non-radical structure did not prevent A. fumigatus growth. Furthermore, the introduction of succinic group in the peptide substrate resulted in the loss of alkoxyamine antifungal properties. Our work reports a novel chemical strategy for antifungal therapy against A. fumigatus based on the pathogen enzyme-mediated generation of toxic radicals. Significantly, these findings are timely since they could overcome the emerged resistance to conventional drugs that are known to target defined pathogen biologic mechanisms such as ergosterol synthesis. Full article

Lichens, symbiotic organisms with a high tolerance to harsh environments, possess a greater diversity of sterols than other organisms. Sterols are involved in maintaining membrane integrity, hormone biosynthesis, and signal transduction. (1) Background: A characteristic feature of lichen sterols is a high degree of unsaturation, which influences membrane properties. Desaturases play an important role in the synthesis of unsaturated sterols, in particular, sterol C-5 desaturase (ERG3), which controls the conversion of episterol to ergosterol. Earlier, we demonstrated that the treatment of the lichen Peltigera canina with low and elevated temperatures results in changes in the levels of episterol and ergosterol. (2) Methods: Here, for the first time, we identified ERG3 in P. canina and, using an in silico analysis, we showed that PcERG3 belongs to the superfamily of fatty acid hydrolyases. A phylogenetic analysis was conducted to determine the evolutionary relationships of PcERG3. (3) Results: A phylogenetic analysis showed that PcERG3 clusters with ERG3 from other Peltigeralian and non-Peltigeralian lichens and also with ERG3 from free-living fungi. This suggests that PcERG3 has an ancient evolutionary origin and is related to fungi with lichenized ancestors, e.g., Penicillium. The differential expression of PcERG3 in response to temperature stress, a dehydration/rehydration cycle, and heavy metal exposure suggests that it plays a crucial role in maintaining the balance between more and less saturated sterols and, more generally, in membrane functioning. The multifaceted response of P. canina to abiotic stresses was documented by simultaneously measuring changes in the expression of PcERG3, as well as the genes encoding the heat shock proteins, PcHSP20 and PcHSP98, and PcSOD1, which encodes the antioxidant enzyme superoxide dismutase. (4) Conclusions: These findings suggest that PcERG3 is similar to the sterol C-5 desaturases from related and free-living fungi and plays important roles in the molecular mechanisms underlying the tolerance of lichens to environmental stress. Full article

Chagas disease, caused by the protozoan parasite Trypanosoma cruzi (T. cruzi), continues to pose significant public health challenges due to the toxicity, poor tolerability, and limited efficacy of current treatments. Targeted protein degradation (TPD) using proteolysis-targeting chimeras (PROTACs) represents a novel therapeutic avenue by leveraging the ubiquitin–proteasome system to selectively degrade essential parasite proteins. This review introduces the conceptual framework of “TrypPROTACs” as a prospective strategy for T. cruzi, integrating a comprehensive analysis of druggable targets across critical biological pathways, including ergosterol biosynthesis, redox metabolism, glycolysis, nucleotide synthesis, protein kinases, molecular chaperones such as heat shock protein 90 (Hsp90), and epigenetic regulators such as T. cruzi bromodomain factor 3 (TcBDF3). It is important to note that no TrypPROTAC compound has yet been synthesized or experimentally validated in T. cruzi; the approach discussed herein remains theoretical and forward-looking. Representative inhibitors for each target class are compiled, highlighting potency, selectivity, and structural features relevant to ligand design. We also examine the parasite’s ubiquitination machinery and compare it to the human system to identify putative E3 ubiquitin ligases. Key aspects of linker engineering and ternary complex stabilization are discussed, alongside potential validation techniques such as the cellular thermal shift assay (CETSA) and bioluminescence resonance energy transfer (NanoBRET). Collectively, these insights outline a roadmap for the rational design of TrypPROTACs and support the feasibility of expanding targeted protein degradation strategies to neglected tropical diseases. Full article

Background/Objectives: This study investigates the physical, rheological, and antioxidant properties of nano-liposomal formulations encapsulating Fumaria officinalis L. (fumitory) extract, focusing on their stability and performance under ultraviolet (UV) exposure, as well as polyphenol release within simulated skin conditions in a Franz diffusion cell. Methods: Liposomal formulations, composed of phospholipids with or without β-sitosterol or ergosterol, were evaluated for their encapsulation efficiency, liposome size, size distribution, zeta potential, viscosity, surface tension, density, oxidative stability, antioxidant capacity, and polyphenol recovery. Results: Encapsulation efficiency was the highest in phospholipid liposomes (72.2%) and decreased with the incorporation of sterols: 66.7% for β-sitosterol and 62.9% for ergosterol liposomes. Encapsulation significantly increased viscosity and reduced surface tension compared to the plain liposomes, suggesting modified interfacial behavior. The inclusion of fumitory extract significantly increased the viscosity of liposomes (from ~2.5 to 6.09–6.78 mPa × s), consistent with the observed reduction in particle size and zeta potential. Antioxidant assays (thiobarbituric acid reactive substances—TBARS, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid—ABTS, and 2,2-diphenyl-1-picrylhydrazyl—DPPH) confirmed enhanced lipid peroxidation inhibition and radical scavenging upon encapsulation, with ABTS activity reaching up to 95.05% in sterol-containing liposomes. Release studies showed that the free extract exhibited the fastest polyphenol diffusion (5.09 × 10⁻⁹ m²/s), while liposomes demonstrated slower/controlled release due to bilayer barriers. UV-irradiated liposomes released more polyphenols than untreated ones, particularly in the sterol-containing formulations, due to oxidative destabilization and pore formation. Conclusions: These findings highlight the potential of fumitory extract-loaded liposomes as stable, bioactive carriers with tunable polyphenol antioxidant release properties for dermal applications. Overall, liposomal formulations of fumitory extract exhibit significant potential for further development as a pharmaceutical, cosmetic, or dermo-cosmetic ingredient for use in the prevention and treatment of various skin disorders. Full article

Air pollutants are significant environmental factors that contribute to the exacerbation of respiratory, cardiopulmonary, and skin diseases in East Asia, and their impact is based on particle size. Natural products represent a promising and sustainable strategy for reducing the adverse effects of air pollutants on health. Cordyceps spp. have been integral to traditional Chinese medicine. Recently, their fruiting bodies and related supplements have gained popularity. The physiological effects of Cordyceps species are well documented and attributed to their chemical constituents, such as cordycepin, polysaccharides, cordymin, glycoprotein, ergosterol, and other bioactive extracts. Cordyceps supplementation may support lung health and enhance respiratory function. Although further clinical data are necessary, many preclinical studies have found a connection between Cordyceps and improved lung health. In addition, preclinical and clinical studies have indicated that Cordyceps and its derivatives (e.g., Ningxinbao, Corbrin, and Jinshuibao capsules) protect against vascular diseases by modulating key molecular pathways. This review provides insights into the potential of Cordyceps for clinical application in the management of air pollutant-related respiratory and vascular diseases. Full article

Background: Renal injury is a critical health issue in pet dogs, often exacerbated by drug-induced nephrotoxicity such as gentamicin (GM). This study investigated the protective effects of ergosterol (Erg), a natural compound from edible mushrooms, against GM-induced damage in Madin–Darby canine kidney (MDCK) cells. Methods: MDCK cells were treated with GM (0.5–3 mmol/L) for 12 h to establish injury. Erg (1 to 32 μg/mL) was pretreated for 12 h before GM exposure (2 mmol/L). Cell viability, nitric oxide (NO), lactate dehydrogenase (LDH), oxidative stress markers (SOD, GSH, CAT, MDA), inflammatory cytokines (IL-1β, IL-6, TNF-α), renal function indicators (Scr, BUN), and autophagy/apoptosis-related proteins (ATG5, Beclin1, P62, BAX, BCL-2) were assessed via CCK-8, ELISA, fluorescence staining, and Western blot. Statistical significance (p < 0.05) was determined by ANOVA and LSD post hoc tests. Results: GM (2 mmol/L) significantly reduced cell viability (p < 0.01) and elevated NO and LDH levels (p < 0.01). Erg pretreatment (4–8 μg/mL) restored cell viability (p < 0.01), suppressed NO (p < 0.01) and LDH release (p < 0.01), and enhanced antioxidant enzyme activities (SOD, GSH, CAT; p < 0.01). Erg attenuated GM-induced reactive oxygen species (ROS) overproduction (p < 0.01) and decreased pro-inflammatory cytokines (IL-1β, IL-6, TNF-α; p < 0.01). Renal markers Scr and BUN were reduced (p < 0.01). Mechanistically, Erg upregulated autophagy proteins ATG5 and Beclin1 (p < 0.01), reduced P62 accumulation (p < 0.01), and lowered the BAX/BCL-2 ratio (p < 0.01). Conclusions: Erg protects MDCK cells from GM-induced nephrotoxicity by restoring autophagy flux, suppressing mitochondrial apoptosis, and mitigating oxidative stress and inflammation. These findings highlight Erg’s potential as a natural therapeutic agent for canine renal injury. Further in vivo studies are needed to validate its clinical efficacy. Full article