Isolation, Identification, and Bioactivity of Monoterpenoids and Sesquiterpenoids from the Mycelia of Edible Mushroom Pleurotus cornucopiae

Clypeasterol, a novel aromatic ergosterol skeleton from the mushroom Entoloma clypeatum

Chemical investigation of the wild mushroom Entoloma clypeatum led to the isolation of one new A-nor B-aromatic C28 steroid (1), along with eight known compounds (2-9) from this mushroom. As far as we know, compound 1 represents an unprecedented type of natural product. The structure of the new compound was elucidated based on extensive spectroscopic data analysis of HR-ESI-MS, 1D, and 2D NMR, while the relative configuration was confirmed by NOESY correlations. In addition, the anti-inflammatory activity of compound 1 was evaluated against LPS induced NO production in RAW 264.7 macrophages. Compound 1 exhibited a moderate anti-inflammatory activity with an IC50 value of 24.56 ± 1.72 μM.

Isolation and target identification of antihepatoma polyprenylphenols from the edible mushroom Suillus granulatus

Eight polyprenylphenol derivatives were isolated from the wild edible mushroom Suillus granulatus, including seven novel compounds, named suillin F-L (2-8), and one previously identified compound (1). The structures of the new compounds were elucidated using HR-ESI-MS and 1D and 2D NMR data. The absolute configuration of compound 8 was assigned based on the comparison of the experimental and calculated ECD data. All isolated compounds were evaluated for their cytotoxicity against HepG2 cancer cell lines. Compounds 1 and 3-6 demonstrated significant antitumor activity compared to the positive control (cisplatin), with IC50 values ranging from 8.19 to 13.97 μM. Furthermore, DARTS assay and LC-MS/MS analysis were used to identify HSP90AA1 as the direct target of compound 5, and the interaction between compound 5 and HSP90AA1 was verified by molecular docking.

Bioassay-guided isolation of three new alkaloids from Suillus bovinus and preliminary mechanism against ginseng root rot

In order to control the occurrence of ginseng root rot caused by Fusarium solani (Mart.) Sacc., the antifungal compounds of the mushroom Suillus bovinus were investigated. And three new alkaloids (1-3), named bovinalkaloid A-C, along with one known analog (4), were isolated and identified by bioassay-guided isolation and spectroscopic analyses. Compound 1 strongly inhibited the mycelial growth and spore germination of F. solani with minimum inhibitory concentration of 2.08 mM. Increases in electrical conductivity, nucleic acid, and protein contents, and decreases in lipid content showed that the membrane permeability and integrity were damaged by compound 1. Compound 1 also increased the contents of malondialdehyde and hydrogen peroxide and the activities of antioxidant enzymes, indicating that lipid peroxidation had taken place in F. solani. Compound 1 may serve as a natural alternative to synthetic fungicides for the control of ginseng root rot.

Therapeutic Potential of Fungal Terpenes and Terpenoids: Application in Skin Diseases

Terpenes and their derivatives comprise a diverse group of natural compounds with versatile medicinal properties. This article elucidates the general characteristics of fungal terpenes and terpenoids, encompassing their structure and biogenesis. The focal point of this work involves a comprehensive overview of these compounds, highlighting their therapeutic properties, mechanisms of action, and potential applications in treating specific skin conditions. Numerous isolated terpenes and terpenoids have demonstrated noteworthy anti-inflammatory and anti-microbial effects, rivalling or surpassing the efficacy of currently employed treatments for inflammation or skin infections. Due to their well-documented antioxidant and anti-cancer attributes, these compounds exhibit promise in both preventing and treating skin cancer. Terpenes and terpenoids sourced from fungi display the capability to inhibit tyrosinase, suggesting potential applications in addressing skin pigmentation disorders and cancers linked to melanogenesis dysfunctions. This paper further disseminates the findings of clinical and in vivo research on fungal terpenes and terpenoids conducted thus far.

Concise and collective total syntheses of 2,4-disubstituted furan-derived natural products from hydroxyoxetanyl ketones

The furan moiety, prevalent in bioactive natural products and essential drugs, presents intriguing structural features that have spurred our exploration into streamlined chemical synthesis routes for related natural products. In this study, we demonstrate the concise total synthesis of eight 2,4-disubstituted furan-derived natural products (including methylfuroic acid, rabdoketones A and B, paleofurans A and B, tournefolin C, and shikonofurans A and B). Our methodology revolves around the utilization of hydroxyoxetanyl ketones as pivotal intermediates. The approach encompasses transformations such as selective organo-catalyzed cross-ketol addition, synthesis of hydroxymethyl-tethered furans through Bi(OTf)3 catalyzed dehydrative cycloisomerization of α-hydroxyoxetanyl ketones, and a hydrogen atom transfer (HAT)-mediated oxidation of primary alcohols into the corresponding acids. This comprehensive synthetic strategy highlights the versatility of hydroxyoxetanyl ketones as invaluable building blocks in the synthesis of furan-containing natural products.

Medicinal Mushrooms: Their Bioactive Components, Nutritional Value and Application in Functional Food Production-A Review

Medicinal mushrooms, e.g., Lion's Mane (Hericium erinaceus (Bull.) Pers.), Reishi (Ganoderma lucidum (Curtis) P. Karst.), Chaga (Inonotus obliquus (Ach. ex Pers.) Pilát), Cordyceps (Ophiocordyceps sinensis (Berk.) G.H. Sung, J.M. Sung, Hywel-Jones and Spatafora), Shiitake (Lentinula edodes (Berk.) Pegler), and Turkey Tail (Trametes versicolor (L.) Lloyd), are considered new-generation foods and are of growing interest to consumers. They are characterised by a high content of biologically active compounds, including (1,3)(1,6)-β-d-glucans, which are classified as dietary fibre, triterpenes, phenolic compounds, and sterols. Thanks to their low-fat content, they are a low-calorie product and are classified as a functional food. They have a beneficial effect on the organism through the improvement of its overall health and nutritional level. The biologically active constituents contained in medicinal mushrooms exhibit anticancer, antioxidant, antidiabetic, and immunomodulatory effects. In addition, these mushrooms accelerate metabolism, help fight obesity, and slow down the ageing processes thanks to their high antioxidant activity. The vast therapeutic properties of mushrooms are still not fully understood. Detailed mechanisms of the effects of medicinal mushrooms on the human organism still require long-term clinical studies to confirm their nutraceutical effects, their safety of use, and their dosage. Medicinal mushrooms have great potential to be used in the design of innovative functional foods. There is a need for further research on the possibility of incorporating mushrooms into food products to assess the interactions of their bioactive substances with ingredients in the food matrix. This review focuses on the properties of selected medicinal mushrooms and their effects on the human organism and presents current knowledge on the possibilities of their use in the production of functional foods.

Secoergostane- and ergostane-type steroids from Pleurotus cornucopiae var. citrinopileatus

In this study, we described the isolation of an 8,14-secoergostane-type, a 9,11-secoergostane-type, and three ergostane-type steroids from the fruiting bodies of Pleurotus cornucopiae var. citrinopileatus. The structure of (22Z)-3β,5α,11-trihydroxy-9,11-secoergosta-7,22-diene-6,9-dione, previously reported, have been revised to (22E). Their structures were established using NMR, UV, IR, and mass spectroscopic analyses. Three of the isolated compounds were found to exhibit inhibitory activity on the production of nitric oxide in lipopolysaccharide-stimulated RAW264.7 macrophages with IC₅₀ values of 21.3, 17.6, and 23.1 μM, respectively.

Progress in biological activities and biosynthesis of edible fungi terpenoids

The edible fungi have both edible and medicinal functions, in which terpenoids are one of the most important active ingredients. Terpenoids possess a wide range of biological activities and show great potential in the pharmaceutical and healthcare industries. In this review, the diverse biological activities of edible fungi terpenoids were summarized with emphasis on the mechanism of anti-cancer and anti-inflammation. Subsequently, this review focuses on advances in knowledge and understanding of the biosynthesis of terpenoids in edible fungi, especially in the generation of sesquiterpenes, diterpenes, and triterpenes. This paper is aim to provide an overview of biological functions and biosynthesis developed for utilizing the terpenoids in edible fungi.

Dereplication of extracts from nutraceutical mushrooms Pleurotus using molecular network approach

Pleurotus is an edible mushroom from the well-known genus of Basidiomycetes; it is the second-most commonly consumed mushroom worldwide. This genus is characterized by the presence of steroids, fatty acids, and polysaccharides. Recently, Pleurotus has become popular as a functional food owing to its health benefits, primarily because they are a source of vitamins, fibers, minerals, and lipids. In natural products chemistry, dereplication techniques identify bioactive molecules from natural sources such as plants and fungi without isolating or characterizing molecules. We used dereplication techniques aided by the Global Natural Products Social Molecular Network to analyze the chemical composition of the methanolic extracts of six Pleurotus species (P. sapidus, P. ostreaus, P. ostreaus var. Florida, P. djamor, P. citrinopileatus, and P. pulmonarius), to identify bioactive molecules with nutraceutical properties. Using this technique, we identified several molecular families, including eight fatty acids and seven steroids. Our findings suggest that dereplication is a relatively rapid tool for characterizing fungal species and determining their nutraceutical value.

Secondary Metabolites Produced by Coculture of Pleurotus ostreatus SY10 and Pleurotus eryngii SY302

A new isovaleryl-monoterpene, pleurotusin A (1), and a new cyclopentenone derivative, pleurotusin B (7), together with five related known terpenoids (2-6), were isolated from the coculture broth of two edible fungi, Pleurotus ostreatus SY10 and Pleurotus eryngii SY302. The absolute configurations of 1 and 7 were elucidated by comprehensively using the density functional theory calculation of NMR and ECD data, DP4+ probability analysis, Mo2(OAc)4-based CD experiment and optical rotation. The antimicrobial activities of these compounds except for the unstable compound 7, were evaluated against two types of human-pathogenic fungi, Candida albicans and Cryptococcus neoformans, and three types of human-pathogenic bacteria, Staphylococcus aureus, Escherichia coli,  and Shigella sp. Compound 1 displayed moderate activity against S. aureus with an MIC50 value of 90.3 μM. In addition, the antioxidant activities of high-yielding 2-6 were tested using DPPH, and compound 4 showed moderate activity with an EC50 value of 573 μM.

A RESEARCH ON QUALITY EVALUATION OF EIGHT WILD EDIBLE MACROFUNGI COLLECTED FROM EAST MEDITERRANEAN REGION OF TURKEY

Eight edible macrofungal species ( Suillus collinitus, Rhizopogon roseolus, Lactarius sanguifluus, Lycoperdon molle, Ganoderma adspersum, Pleurotus cornucopiae, Lycoperdon perlatum, Macrolepiota procera ) grown in Osmaniye were studied. Besides the evaluation of fresh forms, the mushrooms were dried at 40˚C, and the color, texture, protein and mineral contents, and bioactivities (total phenolic content, (TPC) and antioxidant activities by DPPH, FRAP and ABTS techniques) were determined. The protein, macro and micro mineral contents of dried samples were in range of 11.31-55.31%, 132.75-50844.80 and 0.30-812.05 mg/kg, respectively. TPC of fresh samples were 10227.13-42216.89 mg gallic acid equivalent (GAE)/kg dry matter (DM) in methanolic solution, 3625.31-28809.99 mg GAE/kg DM in ethanolic solution, and decreased by drying process. ABTS method yielded higher results in fresh specimens, however DPPH method in ethanol and FRAP method in methanol were the superior in dried forms.

Two new compounds from edible mushroom Sarcomyxa edulis

Chemical investigation of the edible mushroom Sarcomyxa edulis led to the isolation of one new highly degraded sterol (1), and one new β-carboline alkaloid (2), along with nine known compounds (3-11) for the first time from this mushroom. The structures of new compounds were elucidated using HR-ESI-MS data and NMR spectroscopy. In addition, anti-inflammatory activity of new compounds was evaluated against lipopolysaccharide-induced NO production in RAW 264.7 macrophages. Compound 2 exhibited a good anti-inflammatory activity with IC₅₀ value of 9.88 ± 0.48 μM, and compound 1 exhibited a weak inhibitory effect with IC₅₀ value of 71.36 ± 5.11 μM.

Nutraceutical potential of mushroom bioactive metabolites and their food functionality

Numerous mushroom bioactive metabolites, including polysaccharides, eritadenine, lignin, chitosan, mevinolin, and astrakurkurone have been studied in life-threatening conditions and diseases such as diabetes, cardiovascular, hypertension, cancer, DNA damage, hypercholesterolemia, and obesity attempting to identify natural therapies. These bioactive metabolites have shown potential as antiviral and immune system strengthener natural agents through diverse cellular and physiological pathways modulation with no toxicity evidence, widely available, and inexpensive. In light of the emerging literature, this paper compiles the most recent information describing the molecular mechanisms that underlie the nutraceutical potentials of these mushroom metabolites suggesting their effectiveness if combined with existing drug therapies while discussing the food functionality of mushrooms. The findings raise hope that these mushroom bioactive metabolites may be utilized as natural therapies considering their therapeutic potential while anticipating further research designing clinical trials and developing new drug therapies while encouraging their consumption as a natural adjuvant in preventing and controlling life-threatening conditions and diseases. PRACTICAL APPLICATIONS: Diabetes, cardiovascular, hypertension, cancer, DNA damage, hypercholesterolemia, and obesity are among the world's largest life-threatening conditions and diseases. Several mushroom bioactive compounds, including polysaccharides, eritadenine, lignin, chitosan, mevinolin, and astrakurkurone have been found potential in tackling these diseases through diverse cellular and physiological pathways modulation with no toxicity evidence, suggesting their use as nutraceutical foods in preventing and controlling these life-threatening conditions and diseases.

Novel hypoglycemic compounds from wild mushroom Paxillus involutus

Wild mushrooms are an important source of secondary metabolites possessing a broad range of biological activities. In this study, eight new compounds, named furanopaxin A-F (1-6), deoxybisinvolutone (7), and coumarinvol (8) along with two known compounds were isolated from fruiting bodies of the wild mushroom Paxillus involutus (Batsch) Fr. Their structures were established based on HR-ESI-MS and 1D and 2D NMR spectroscopic data. The results of hypoglycemic assays indicated that compounds 5-8 possessed significant α-glucosidase inhibitory activities, with IC₅₀ values ranging from 14.65 ± 1.68 to 47.55 ± 1.47 μM, and each compound could enhance glucose consumption in insulin-resistance HepG2 cells. Further analysis by molecular docking implied that compounds 5-8 could interact with the amino acid residues of α-glucosidase, supporting the hypoglycemic activity of the compounds.

Novel 2,5-Diarylcyclopentenone Derivatives from the Wild Edible Mushroom Paxillus involutus and Their Antioxidant Activities

Wild edible mushrooms are important as a source of nutraceuticals and for the discovery of bioactive metabolites as pharmaceuticals. In this work, 10 rare 2,5-diarylcyclopentenone derivatives were isolated from the wild edible mushroom Paxillus involutus (Batsch) Fr., including eight novel compounds termed involutenone A-H (1-8) and two previously identified compounds (9-10). Their structures were established using high-resolution electrospray ionization mass spectroscopy and 1D and 2D nuclear magnetic resonance data. The absolute configurations of compounds 1-3 and 6-8 were assigned based on the comparison of the experimental and calculated electronic circular dichroism data. The antioxidant activities of 1-8 were tested through DPPH free radical scavenging, hydroxyl radical scavenging, and superoxide anion radical scavenging assays. Compounds 3, 5, 6, and 7 demonstrated significant antioxidant activity compared to the positive control (tert-butylhydroquinone). These compounds could be effective natural antioxidants with considerable pharmaceutical value.

New bioactive α-pyrone from wild mushroom Paxillus involutus

Chemical investigation of Paxillus involutus (Batsch) Fr. led to the isolation of a pair of new enantiomers (E)-5-(4-methoxy-2-oxo-2H-pyran-6-yl)pent-4-en-1-yl 2-hydroxypropanoate (1a/1b) along with 14 known compounds (2-15) for the first time from this mushroom. The structures of new compounds were elucidated based on extensive spectroscopic data analysis of MS, 1D and 2D NMR, and their absolute configurations were confirmed by comparison of the experimental and calculated ECD data. Compounds 1a and 1b exhibited radical scavenging activities with IC₅₀ values ranging from 10.39 ± 2.26 to 20.43 ± 3.74 μg/mL. Compounds 1a and 1b also showed moderate anti-tyrosinase activity with IC₅₀ value of 25.66 ± 2.84 and 26.82 ± 3.19 μg/mL.

Immunomodulatory Effects of Edible and Medicinal Mushrooms and Their Bioactive Immunoregulatory Products

Mushrooms have been valued as food and health supplements by humans for centuries. They are rich in dietary fiber, essential amino acids, minerals, and many bioactive compounds, especially those related to human immune system functions. Mushrooms contain diverse immunoregulatory compounds such as terpenes and terpenoids, lectins, fungal immunomodulatory proteins (FIPs) and polysaccharides. The distributions of these compounds differ among mushroom species and their potent immune modulation activities vary depending on their core structures and fraction composition chemical modifications. Here we review the current status of clinical studies on immunomodulatory activities of mushrooms and mushroom products. The potential mechanisms for their activities both in vitro and in vivo were summarized. We describe the approaches that have been used in the development and application of bioactive compounds extracted from mushrooms. These developments have led to the commercialization of a large number of mushroom products. Finally, we discuss the problems in pharmacological applications of mushrooms and mushroom products and highlight a few areas that should be improved before immunomodulatory compounds from mushrooms can be widely used as therapeutic agents.

A critical review on submerged production of mushroom and their bioactive metabolites

Mushrooms are ubiquitous in nature. Even though humankind has been consuming mushrooms for ages, their medicinal and nutraceutical properties are not used to its fullest potential in the present market. Edible mushrooms are not only a cheap and nutritious option to mitigate malnutrition, but they also produce effective biomass. Submerged fermentation (SmF) is not only a cost-effective method to produce biomass along with exquisite bioactive metabolites but it also reduces the chances of contamination and the time of production. Therefore, this study unveils the bioactive metabolites being produced by mushrooms. Moreover, it also showcases the recent advances in the areas of bio-active compounds and their judicious implementations in daily life and pharmaceutical industries. Moreover, there is a distinct lack in utilizing the potential benefits of bioactive compounds from mushroom unless in vivo and in vitro studies are demonstrated.

Pleurocorols A and B: rearranged steroids from the fruiting bodies of Pleurotus cornucopiae

Pleurocorols A and B, unprecedented steroids with an 11(9 → 8)abeo-ergostane and a 5(6 → 7), 11(9 → 7)diabeo-ergostane skeleton, respectively, were isolated from Pleurotus cornucopiae.

Pleurotus spp. Cultivation on Different Agri-Food By-Products: Example of Biotechnological Application

Agri-food industry generally produces huge volumes of wastes all over the world, and their disposal is a threat to the environment and public health. The chemical composition of most of these wastes make them be defined as lignocellulosic materials, so they could be a suitable substrate for solid-state fermentation process operated by mushrooms. White-rot fungi are well known for their degradation ability of lignocellulosic material, and many scientific works reported the use of different substrates for their production. Biotechnological treatments of agri-food wastes by mushrooms could be considered an eco-friendly solution to reuse and valorize them, besides to reduce their environmental impact. In this way, wastes would be transformed into new resources to produce added-value food products, besides representing an economic return for the same industries. The aim of this review is to provide an overview of the recent literature concerning the use of different agri-food residues as growth substrates for Pleurotus spp. cultivation, with attention to their effects on the growth and chemical composition of the cultivated mushrooms.

Antitumor potential of new low molecular weight antioxidative preparations from the white rot fungus Cerrena unicolor against human colon cancer cells

The aim of this study was to investigate the anticancer and antioxidant activities of low molecular weight subfractions isolated from secondary metabolites produced by the wood degrading fungus Cerrena unicolor. Human colon cancer cells (stage I) HT-29 and human normal colon epithelial cells CCD 841 CoTr were used in the research. The present study demonstrated that the low molecular weight subfractions exhibited inhibitory activity towards human colon cancer cells HT-29 at a concentration range of 25–200 μg/mL. All 6 subfractions inhibited proliferation of cells down to 47.5–9.2% at the highest concentrations in a dose-dependent manner. The most desired activity was exhibited by subfractions S, 3, 4, and 5, as the proliferation of HT-29 cells was inhibited to the greatest extent (16.5, 47.5, 42.7, and 26.1% of the control, respectively), while the effect on CCD 841 CoTr cells was the mildest (inhibition to 54.4, 71.4, 79.4, and 53.4%, compared to the control, respectively). The microscopic observation revealed that all extracts induced programmed cell death, i.e. apoptosis (up to 44.4% (subfraction 6) towards HT-29 and less than 20% (most fractions) towards CCD 841 CoTr), with no or a significantly low level of necrosis in both cell lines at the same time.

Transition-metal-free C–C σ-bond activation of α-aryl ketones and subsequent Zn-catalyzed intramolecular cyclization: synthesis of tetrasubstituted furans

Atom-economical synthesis of tetrasubstituted furans from α-aryl ketones and alkynones through base-promoted cleavage of unstrained C–C single bonds of ketones and subsequent Zn-catalyzed cyclization.

Catalytic palladium-oxyallyl cycloaddition

Exploration of intermediates that enable chemoselective cycloaddition reactions and expeditious construction of fused- or bridged-ring systems is a continuous challenge for organic synthesis. As an intermediate of interest, the oxyallyl cation has been harnessed to synthesize architectures containing seven-membered rings via (4+3) cycloaddition. However, its potential to access five-membered skeletons is underdeveloped, largely due to the thermally forbidden (3+2) pathway. Here, the combination of a tailored precursor and a Pd(0) catalyst generates a Pd-oxyallyl intermediate that cyclizes with conjugated dienes to produce a diverse array of tetrahydrofuran skeletons. The cycloaddition overrides conventional (4+3) selectivity by proceeding through a stepwise pathway involving a Pd-allyl transfer and ring closure sequence. Subsequent treatment of the (3+2) adducts with a palladium catalyst converts the heterocycles to the carbocyclic cyclopentanones.

Three New Heptelidic Acid Derivatives from the Culture of Mushroom Lentinellus ursinus

Three new heptelidic acid derivatives (1-3) including two new dimeric esters and two known heptelidic acid analogues (4 and 5) were isolated from the solid culture of mushroom Lentinellus ursinus. The structures of new compounds were confirmed by the analysis of NMR and HRESIMS spectroscopic data. The biosynthetic origin of compounds 1-5 was postulated. Compounds 1-5 exhibited no antibacterial activity against Staphylococcus aureus and Escherichia coli at the dose of 100 μM.

Three bisabolane-type sesquiterpenes from edible mushroom Pleurotus eryngii

Three bisabolane-type sesquiterpenes (1-3) were isolated from the fruiting bodies of king trumpet mushrooms (Pleurotus eryngii), together with a known compound (4). All isolated compounds were evaluated for their inhibitory effects on nitric oxide (NO) production. Among these, 2 exhibited a moderate inhibitory effect on NO production with an IC₅₀ of 90.9 μM.

Asperpyrone F, a new dimeric naphtho-γ-pyrone from the edible fungus Pleurotus ostreatus

A new dimeric naphtho-γ-pyrone, asperpyrone F (1), along with six known ones, asperpyrones B (2) and C (3), fonsecinones A (4) and B (5), aurasperones A (6) and E (7), have been isolated from the solid culture of the edible fungus Pleurotus ostreatus. The structures of 1-7 were determined mainly by NMR and MS experiments. The absolute configuration of compound 1 was assigned via the circular dichroism (CD) data analysis. Compounds 1-7 showed modest antioxidant and immunomodulatory activities. All compounds were isolated from the fungus P. ostreatus for the first time.

Asymmetric total synthesis of pleurospiroketals A and B

The first asymmetric total synthesis of pleurospiroketals A and B has been accomplished in 16 steps from 5-methyl-5-hexenoic acid.

Three new amino acid derivatives from edible mushroom Pleurotus ostreatus

Three new amino acid derivatives, oxalamido-L-phenylalanine methyl ester (1), oxalamido-L-leucine methyl ester (2), and lumichrome hydrolyzate (3), together with nine known compounds (4-12), were isolated from the solid culture of edible mushroom Pleurotus ostreatus. Their structures were elucidated on the basis of extensive spectroscopic analysis. The absolute configurations of 1 and 2 were established by the chiral synthesis and confirmed by circular dichroism (CD) analysis of their total synthesis products and natural isolates. All new compounds were evaluated for their antioxidant effects, antimicrobial activities, and cytotoxic activity. Compounds 1-3 showed weak antifungal activities against Candida albicans with minimum inhibitory concentration (MIC) value of 500 μg/ml.

Antimicrobial Activities and Time-Kill Kinetics of Extracts of Selected Ghanaian Mushrooms

The rapid rise of antimicrobial resistance is a worldwide problem. This has necessitated the need to search for new antimicrobial agents. Mushrooms are rich sources of potential antimicrobial agents. This study investigated the antimicrobial properties of methanol extracts of Trametes gibbosa, Trametes elegans, Schizophyllum commune, and Volvariella volvacea. Agar well diffusion, broth microdilution, and time-kill kinetic assays were used to determine the antimicrobial activity of the extracts against selected test organisms. Preliminary mycochemical screening revealed the presence of tannins, flavonoids, triterpenoids, anthraquinones, and alkaloids in the extracts. Methanol extracts of T. gibbosa, T. elegans, S. commune, and V. volvacea showed mean zone of growth inhibition of 10.00 ± 0.0 to 21.50 ± 0.84, 10.00 ± 0.0 to 22.00 ± 1.10, 9.00 ± 0.63 to 21.83 ± 1.17, and 12.00 ± 0.0 to 21.17 ± 1.00 mm, respectively. The minimum inhibitory concentration of methanol extracts of T. gibbosa, T. elegans, S. commune, and V. volvacea ranged from 4.0 to 20, 6.0 to 30.0, 8.0 to 10.0, and 6.0 to 20.0 mg/mL, respectively. Time-kill kinetics studies showed that the extracts possess bacteriostatic action. Methanol extracts of T. gibbosa, T. elegans, S. commune, and V. volvacea exhibited antimicrobial activity and may contain bioactive compounds which may serve as potential antibacterial and antifungal agents.

Biochemical characteristics of a novel protease from the basidiomycete Amanita virgineoides

The characterization of a novel protease from Amanita virgineoides is described. The A. virgineoides protease was purified to homogeneity using Q-Sepharose, carboxymethyl-cellulose, diethylaminoethyl-cellulose, and a gel filtration step on Superdex 75. The molecular mass of the purified protease was estimated to be 16.6 kDa. The protease was purified 32.1-fold, and its specific activity was 301.4 U/mg. The optimum pH was 4.0, and the optimum temperature was 50 °C. Kinetic constants (K_m , V_max ) were determined under the optimum reaction conditions, with K_m and V_max , being 3.74 mg/mL and 9.98 μg mL^-1 Min^-1 , respectively. The activity of the protease was curtailed by Cu²⁺ , Pb²⁺ , Fe³⁺ , Cd²⁺ , and Hg²⁺ ions but enhanced by Mg²⁺ , Ca²⁺ , and K⁺ ions at low concentrations. The protease activity was adversely affected by ethylene diamine tetraacetic acid, suggesting that it is a metalloprotease. Four peptide sequences were obtained from liquid chromatography-tandem mass spectrometry, including KQALSGIR, TIAMDGTEGLVR, VALTGLTVAEYFR, and AGAGSATLSMAYAGAR, which showed 86%, 64%, 60%, and 75% identity with peptides of Hypsizygus marmoreus, Dacryopinax sp. DJM-731 SS1, Trametes versicolor FP-101664 SS1, and Paxillus involutus ATCC 200175, respectively. The newly isolated protease showed good hydrolytic activity and biochemical characteristics, which expanded the knowledge of biologically active proteins and provided further insight on this poisonous fungus.

New apoptosis-inducing sesquiterpenoids from the mycelial culture of Chinese edible fungus Pleurotus cystidiosus

Two new bisabolane-type sesquiterpenoids, pleuroton A (1) and pleuroton B (2), and three clitocybulol derivatives, clitocybulol D (3), clitocybulol E (4), and clitocybulol F (5), were obtained from the mycelial culture of edible fungus Pleurotus cystidiosus O. K. Mill by repeated column chromatography over RP-18, Sephadex LH-20, and silica gel. Their structures were determined according to nuclear magnetic resonance data, high-resolution electron impact mass spectrometry, and circular dichroism spectra. These new sesquiterpenoids exhibited significant cytotoxicity against two human prostate cancer DU-145 and C42B cells in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The median inhibitory concentration (IC50) of compounds 1, 2, 3, 4, and 5 was 174, 28, 233, 162, and 179 nM, respectively, against the DU-145 cell and was 104, 52, 163, 120, and 119 nM, respectively, against the C42B cell. Especially, pleuroton B (2) exhibited the strongest cytotoxity among these sesquiterpenoids, which was confirmed by the colony formation assay. Furthermore, pleuroton B (2) could trigger the apoptosis of DU-145 cells through the detection of apoptosis cells using annexin V-FITC staining by flow cytometry, the observation of condensed nuclei in the apoptosis cells, and the western blot analysis for the expression of apoptosis-related proteins Bcl-2, Bak, and Bax. Analysis of structure-activity relationships of these sesquiterpenoids revealed that the unusual functional moiety of pleuroton B should contribute to its significant bioactivity. These results display the pharmacological potential of P. cystidiosus.

Selective synthesis of 2,5-disubstituted furan-3-carboxylates and the isomeric 2,4-disubstituted furan-3-carboxylates

Regioselective formation of 2,5-disubstituted furan-3-carboxylates and the isomeric 2,4-disubstituted furan-3-carboxylates from the same substrates was realized under different reaction condition.