Chemical constituents of Stereum subtomentosum and two other birch-associated basidiomycetes: an interspecies comparative study

Polyprenylated Xanthones Isolated from Garcinia Resins and Their Beneficial Effects on Rice Blast Disease

Five undescribed polyprenylated xanthones (1, 3, 4, 22, and 23) and 27 known compounds were isolated from Garcinia resins, and the antifungal activities of 15 of them were investigated. Compound 7 exhibited notable in vitro antifungal effects against Magnaporthe grisea with an IC50 value of 3.54 μg/mL, superior to isoprothiolane (10.30 μg/mL), and showed an excellent protective efficiency of 78.4% at 200 μg/mL against RB (rice blast), equivalent to isoprothiolane (87.2%). Its antifungal activity may be related to the destruction of the cell membrane and the effect of absorption and utilization of sugar by the mycelium, which was proven by the transcriptome sequencing and preliminary mechanism, showing a good application prospect for replacing agrochemical fungicides in the control of RB disease.

Deep-Sea-Derived Isobisvertinol Targets TLR4 to Exhibit Neuroprotective Activity via Anti-Inflammatory and Ferroptosis-Inhibitory Effects

Neuroinflammation and neuronal cell death are leading causes of death in the elderly and underlie various neurodegenerative diseases. These diseases involve complex pathophysiological mechanisms, including inflammatory responses, oxidative stress, and ferroptosis. Compounds derived from deep-sea fungi exhibit low toxicity and potent neuroprotective effects, offering a promising source for drug development. In this study, we isolated 44 natural products from deep-sea-derived fungi and identified isobisvertinol (17) as a compound with anti-inflammatory and ferroptosis-inhibiting effects. Using LPS-induced microglial inflammation and RSL3-induced neuronal ferroptosis models, we found that 17 targets TLR4 to provide neuroprotection. Molecular docking studies revealed that 17 inhibits TLR4 activation by occupying the hydrophobic pocket at the TLR4-MD2 binding site. Additionally, 17 suppresses TLR4, reducing p38 MAPK phosphorylation, and inhibits ferroptosis by decreasing lipid peroxidation and modulating mitochondrial membrane potential. Metabolomic analysis showed that 17 rescues alterations in multiple metabolic pathways induced by RSL3 and increases levels of antioxidant metabolites, including glutamine, glutamate, and glutathione. In summary, our results indicate that isobisvertinol (17) targets TLR4 in neural cells to reduce inflammation and inhibit p38 MAPK phosphorylation, while regulating metabolic pathways, mainly GSH synthesis, to provide antioxidant effects and prevent ferroptosis in neurons.

Chemical Constituents of the Deep-Sea-Derived Penicillium citrinum W22 and Their Ferroptosis Inhibitory Activity

One new monomeric citrinin analog (1) and 42 known compounds (2-43) were isolated from Penicillium citrinum W22. The structure of 1 was determined by detailed analysis of the 1D and 2D nuclear magnetic resonance (NMR), HRESIMS, and time-dependent density functional theory (TD-DFT)-based electronic circular dichroism (ECD) calculation. Penicitrinol A (2) and methyl 2-(2-acetyl-3,5-dihydroxy-4,6-dimethylphenyl) acetate (11) significantly inhibited renin-angiotensin system-selective lethal 3 (RSL3)-induced ferroptosis with half maximal effective concentration (EC50) values of 1.6 and 34.0 µM, respectively.

Identification of antibacterial constituents from Rhododendron simsii Planch with an activity-guided method

Bacterial infections and antibiotic resistance pose significant public health challenges globally. Natural products serve as valuable sources for discovering antimicrobial agents. Rhododendron simsii Planch, a folk medicine, is traditionally used to treat various inflammatory diseases. In this study, we investigated the antibacterial metabolites derived from R. simsii Planch. Rhodosimsiin A (1), bearing a 1,5-seco-1,6 and 3,6-epoxy grayanane diterpene skeleton, representing a novel 5/6/7/6/5 pentacyclic ring system, and 3β,16α-dihydroxy-6β-ethoxy-14β-acetoxy-grayan-1(5)-ene-10-one (4), which represents the first example of the degradation of C-20 and carbonylation in C-10 diterpenoid, together with two new grayanane diterpenes (2-3), three new triterpenes (13-15), and known analogs (5-12, 16-30), were isolated from the leaves of R. simsii Planch by using the bioassay-guided method. Their structures were elucidated by comprehensive spectroscopic analyses, and absolute configurations were established by single-crystal X-ray diffraction and calculated ECD spectra. Compounds 14, 15, 18, 20, 27, 28, and 30 exhibited potent antibacterial activity with an MIC50 of 1.4-24.3 μg/mL against Staphylococcus aureus. The findings of this research indicate that secondary metabolites derived from R. simsii Planch are promising natural antimicrobial candidates.

Diaporchalasin A, a new PDE4 inhibitory cytochalasin from Conus marmoreus-derived fungus Diaporthe sp. XMA007

A novel cytochalasin named diaporchalasin A (1) bearing a cinnamenyl and an epoxy-macrocycloketone, and a new benzenepropionic acid derivative (2), and two known compounds (3 and 4) were isolated from Conus marmoreus-derived fungus Diaporthe sp. XMA007. Their structures were elucidated through detailed spectroscopic analysis, and the absolute configuration of 1 was determined by conformational analysis and TDDFT-ECD calculation. Their activity evaluation on PDE4 inhibition and breast cancer cell cytotoxicity were conducted, and compound 1 showed moderate inhibition on PDE4.

Two new acorane-type sesquiterpenoids from an endophytic Trichoderma harzianum associated with Paeonia lactiflora Pall

Two new acorane-type sesquiterpenoids, harzianes A and B (1 and 2), together with two known cyclonerodiol-type sesquiterpenoids (3-4) and four known sterols (5-8) were isolated from the endophytic Trichoderma harzianum, associated with the medicinal plant Paeonia lactiflora Pall. Compounds 1 and 2 were identified as a pair of heterotropic isomers by spectroscopic analysis (HR-ESI-MS, 1D and 2D NMR), and their absolute configurations were determined by ECD calculations. All compounds were tested for anti-inflammatory activity, however, none demonstrated such activity.

Iridoids and other constituents from the leaves and stems of Valeriana officinalis var. latifolia

Fifty-nine compounds, including nineteen previously undescribed iridoids (valeriananols A-S) and an undescribed alkaloid (5'-isovaleryl uridine), were isolated from the leaves and stems of Valeriana officinalis var. latifolia. Their structures were elucidated based on Mass spectrometry and NMR spectroscopy. The absolute configuration of valeriananols A-C, E-N, P, Q and S was determined by experimental and calculated electronic circular dichroism. Structurally, valeriananols A and B were two 1,3-seco-iridoids with a 3,6-epoxy moiety, valeriananols K and L were a pair of C-4 epimers, while valeriananol S was a 4'-deoxy iridoid glycoside. In addition, valeriananol P, stenopterin A and patriscabioin C exhibited significant inhibition on nitric oxide production with IC50 values of 10.31, 3.93 and 8.69 μM, respectively. Furthermore, stenopterin A and patriscabioin C showed anti-proliferation activity on the MCF-7 cell line with IC50 values of 17.28 and 13.89 μM, respectively.

Two New Compounds from the Endophytic Fungi of Dryopteris crassirhizoma and Their Antimicrobial Activities

Two endophytic fungi Trichoderma afroharzianum (HP-3) and Alternaria alstroemeriae (HP-7) were isolated and purified from the fresh root of Dryopteris crassirhizoma. Chemical investigation of the two fungi resulted in the isolation of two new phenols 2,4-dihydroxy-3-farnesyl-5-methoxy benzoic acid (1) and 2-hydroxyphenethyl 2-phenylacetate (2), together with 22 known compounds. Their structures were elucidated by NMR, UV, IR, HRESIMS, and comparison to the literature data. Compounds 15 and 16 showed significant antibacterial activity against Micrococcus lysodeikticus with MIC value of 6.25 μg/mL, while 8 and 14 displayed moderate inhibitory activities against several plant pathogenic fungi and clinically important bacterial strains. This is the first study to report the isolation, identification, and antimicrobial properties of metabolites from endophytic fungi of D. crassirhizoma. Our findings may provide lead compounds for the development of new antibacterial agents.

Two new compounds from the Hainan Soft Corals Sinularia tumulosa and Sinularia depressa with their anti-inflammatory or cytotoxic activities

The detailed chemical investigations of the South China Sea soft corals Sinularia tumulosa and Sinularia depressa, yielded two new compounds, namely tumulosterol A (1) and 11'-hydroxy-α-tocopherylquinone (3), along with four related known ones (2, 5-7). Their structures were determined by extensive spectroscopic analysis and comparison with the spectral data previously reported in the literature. In bioassays, compound 1 displayed significant cytotoxic effects against H1975 and MDA-MB-231 cells with IC50 values of 6.0 and 6.3 µM, respectively. In addition, compound 3 exhibited interesting inhibitory effect on lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 cells with IC50 value of 9.5 µM.

Metabolic profiling for the discovery of two rare fusidane-type heterodimers from the fungal endophyte Acremonium pilosum F47

In our process of studying fusidane-type antibiotics, metabolomics-guided chemical investigation on the endophytic Acremonium pilosum F47 led to the isolation of two unique heterodimers, acremonidiols B and C (1 and 2) consisting of a fusidane-type triterpenoid motif and a steroid unit. Four biosynthetically related known natural products including fusidic acid (FA, 3), as well as ergosterol derivatives (4-6) were also obtained. Their structures were determined by the analyses of ESI-HRMS and NMR data. Compounds 1 and 2, as hybrid molecules comprising the fusidane triterpenoid and steroid, are rare in nature. Compared with the clinically used antibiotic FA (3), new compounds 1 and 2 showed no obvious antibiotic activity, indicating the importance of free C-21 carboxyl group for antibacterial activity.

Undescribed C-Glycosylflavones from Corn Silk and Potential Anti-inflammatory Activity Evaluation of Isolates

Phytochemical investigation of corn silk resulted in isolation and characterization of four flavone C-glycosides, chrysoeriol 6-C-β-oliopyranosyl-7-O-β-D-glucopyranoside (1: ), 3'-methoxycassiaoccidentalin A (2: ), chrysoeriol 6-C-β-boivinopyranosyl-7-O-β-D-glucopyranoside (3: ), and ax-4″-OH-3'-methoxymaysin (4: ), a triterpenoid, friedelin (5: ), two sterols, (22E)-5α,8α-epidioxyergosta-6,22-dien-3β-ol (6: ) and 6β-hydroxystigmasta-4,22-diene-3-one (7: ), and a mixture of β-sitosterol and stigmasterol. Compounds 1: and 2: were previously undescribed. Structure elucidation of the isolated compounds was attained using spectral data including 1D and 2D NMR and HRESIMS. Compounds1, 2, 5: , and 6: inhibited iNOS activity in LPS-induced macrophages and decreased nitrite levels by 68.64 ± 4.46, 65.67 ± 6.47, 88.50 ± 0.50, and 94.00 ± 4.00%, respectively, at 50 µM. Compound 5: also showed inhibition of NF-κB (51.00 ± 1.50%). Compounds 1: and 2: induced NAG-1 activity in chondrocytes by 1.80 ± 0.05 and 2.00 ± 0.13 fold, respectively. The extract of corn silk, however, did not exhibit inhibition of iNOS or NF-κB but induced NAG-1 by 1.80 ± 0.51 fold.

Ergostane-Type Sterols From Several Cordyceps Strains

Ergosterol is an essential component for fungi, including entomopathogenic fungi like Cordyceps. Cordyceps has been used as a traditional medicine in Japan and China and possesses various unique ergostane-type sterols, those exhibit bioactivities. In this manuscript, we reported the isolation of 2 new ergostane-type sterols, 1 and 2 along with ten sterols (3-12) from 7 strains of Cordyceps related fungal strains, Cordyceps takaomontana NBRC 101754, Metarhizium owariense NBRC 33258, Polycephalomyces formosus NBRC 109994, Cordyceps tuberculata NBRC 106948, Cordyceps tenuipes NBRC 108997, Cordyceps sp. NBRC 106954, and Tolypocladium paradoxum NBRC 106958 collected fruiting bodies of Ophiocordyceps heteropoda. In addition, the antitrypanosomal activity and antimicrobial activity of isolates were tested to find 6 showed the antitrypanosomal activity, and the minimum inhibitory concentration (MIC) value was confirmed as 1.41 µg/mL. In the antimicrobial assay, the MIC value of 8 against methicillin-resistant Staphylococcus aureus was determined to be 3.1 µg/mL.

Secondary metabolites with diversified structures from an endophytic fungus Colletotrichum gloeosporioides associated with a toxic medicinal plant Tylophora ovata

Six new secondary metabolites, including two new nor-triterpenes (1 and 2), one new sesquiterpene (4), two new α-pyrone derivatives (6 and 7), and one new natural product (5) along with two known compounds (3 and 8) were isolated from an endophytic fungus Colletotrichum gloeosporioides obtained from a toxic medicinal plant Tylophora ovata. Their structures were elucidated by spectroscopic data analyses, while their absolute configurations were determined by CD and X-ray diffraction analyses. The in vitro anti-inflammatory activities of these compounds were evaluated.

Acremocholone, an Anti-Vibrio Steroid from the Marine Mesophotic Zone Ciocalypta Sponge-Associated Fungus Acremonium sp. NBUF150

Mesophotic coral ecosystems (MCEs) represent an underexplored source of intriguing natural products. Efforts to discover bioactive metabolites from sponge-associated fungi in MCEs identified a new steroid, acremocholone (1) and its three known analogs (2-4), from Acremonium sp. NBUF150. The Acremonium sp. NBUF150 was isolated from a Ciocalypta sponge located 70 m deep within the South China Sea. The planar structures and absolute configuration of 1-4 were determined from NMR-derived spectroscopic data, HR-ESI-MS, and X-ray crystallography. Compound 1 exhibited antimicrobial inhibition against Vibrio scophthalmi, V. shilonii and V. brasiliensis at minimum inhibitory concentrations of 8 μg/mL; compound 2 inhibited V. shilonii and V. brasiliensis at 8 and 32 μg/mL, respectively, and compound 4 inhibited growth of V. brasiliensis at 16 μg/mL. Sponge associated fungi from MCEs represent a promising resource of anti-Vibrio drug leads for aquaculture use.

Secondary Metabolites from Hericium erinaceus and Their Anti-Inflammatory Activities

Hericium erinaceus, a culinary and medicinal mushroom, is widely consumed in Asian countries. Chemical investigation on the fruiting bodies of Hericium erinaceus led to the isolation of one new ergostane-type sterol fatty acid ester, erinarol K (1); and eleven known compounds: 5α,8α -epidioxyergosta-6,22-dien-3β-yl linoleate (2); ethyl linoleate (3); linoleic acid (4); hericene A (5); hericene D (6); hericene E (7); ergosta-4,6,8(14),22-tetraen-3-one (8); hericenone F (9); ergosterol (10); ergosterol peroxide (11); 3β,5α,6α,22E-ergosta-7,22-diene-3,5,6-triol 6-oleate (12). The chemical structures of the compounds were determined by 1D and 2D NMR (nuclear magnetic resonance) spectroscopy, mass spectra, etc. Anti-inflammatory effects of the isolated aromatic compounds (5–7, 9) were evaluated in terms of inhibition of pro-inflammatory mediator (TNF-α, IL-6 and NO) production in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophage cells. The results showed that compounds 5 and 9 exhibited moderate activity against TNF-α (IC₅₀: 78.50 μM and 62.46 μM), IL-6 (IC₅₀: 56.33 μM and 48.50 μM) and NO (IC₅₀: 87.31 μM and 76.16 μM) secretion. These results supply new information about the secondary metabolites of Hericium erinaceus and their anti-inflammatory effects.

Saccharides in atmospheric particulate and sedimentary organic matter: Status overview and future perspectives

Saccharides are omnipresent compounds in terrestrial and marine ecosystems. Since the 2000s, their role in environmental and geochemical studies has significantly increased, but only anhydrosaccharides (mainly levoglucosan) have been reviewed. Here we present the wider knowledge about saccharides in organic matter of aerosols, bottom sediments, soils, dust, and sedimentary rocks. The main purpose here is to characterize the possible sources of saccharides, as well as sacharol formation, seasonal variability, and the possible applications in environmental and paleoenvironmental interpretations. Different saccharide sources were designated, including biomass burning, and particulate matter such as pollen, spores, lichen, and fungi, as well as polysaccharide decomposition as possible inputs of monosaccharides. The main focus was on the most common saccharides encountered in environmental samples and sedimentary rocks. These are the mono- and disaccharides glucose, fructose, sucrose, and trehalose, and sacharols arabitol and mannitol. The anhydrosaccharides levoglucosan, mannosan, and galactosan were evaluated as ancient wildfire indicators and industrialization tracers found in lacustrine sediments starting from Pleistocene to contemporary deposits. However, other anhydrosaccharides like xylosan and arabinosan were also found as products of fossil wood burning. These anhydrosaccharides have the potential to be further tracers of hemicellulose burning. Additional recommendations are proposed for future research, including environmental and paleoenvironmental topics that need to be addressed.

A new look at edible and medicinal mushrooms as a source of ergosterol and ergosterol peroxide - UHPLC-MS/MS analysis

Ergosterol (ES) and ergosterol peroxide (EP) are secondary metabolites common for different mushrooms and responsible for health promoting effects, including anti-inflammatory, anticancer, antiviral activity, and reduction of the incidence of cardiovascular disease. In this study, a new method for determination of both ES and EP in mushroom extracts was developed. Two methods for UHPLC-MS/MS with the use of APCI and APPI sources were developed and compared. The UHPLC-APPI-MS/MS method was found to be more effective and convenient for the analysis of both compounds in 21 edible and 9 medicinal mushrooms. Among the investigated mushrooms, M. procera was found to contain the highest level of ES, while G. dryophilus constituted the richest source of EP. Therefore, it can be suggested that mushrooms are a valuable source of ES and EP in everyday human diet and can be used for development of nutraceuticals and functional food ingredients.

Acorenone C: A New Spiro-Sesquiterpene from a Mangrove-Associated Fungus, Pseudofusicoccum sp. J003

Mangrove-derived endophytes are rich in bioactive secondary metabolites with a variety of biological activities. Recently, a fungus Pseudofusicoccum sp. J003 was first isolated by our research group from mangrove species Sonneratia apetala Buch.-Ham. The subsequent chemical investigation of the methanol extract of the culture broth of this strain has led to the isolation of a new sesquiterpenoid named acorenone C (1), two alkaloids (2-3), four phenolic compounds (4-7), and four steroid derivatives (8-11). The new structure of 1 was established by extensive spectroscopic analysis, including 1D, 2D NMR spectroscopy, and HRESIMS. Its absolute configuration was elucidated by experimental ECD and ECD calculation. The in vitro AChE inhibitory, anti-inflammatory, and cytotoxic activities of the selected compounds were evaluated. The results showed that compound 1 showed mild AChE inhibitory activity, with an inhibition rate of 23.34% at the concentration of 50 μM. Compound 9 exerted a significant inhibitory effect against nitric oxide (NO) production in LPS-stimulated RAW 264.7 mouse macrophages, with an inhibition rate of 72.89% at the concentration of 25 μM, better than that of positive control L-NMMA. Compound 9 also displayed obvious inhibition effects on the growth of two human tumor cell lines, HL-60 and SW480 (inhibition rates 98.68 ± 0.97% and 60.40 ± 4.51%, respectively). The antimicrobial activities of the compounds (1-11) against Escherichia coli, Bacillus subtilis, Staphylococcus aureus, and Pseudomonas aeruginosa were also tested; however, none of them showed antimicrobial activities.

Three New Metabolites From the Marine-Derived Fungus Aspergillus sp. WHUF03110

Two new xanthone derivatives, spinosusones A (1) and B (2), and a new tryptoquivaline analogue, asperdiazapinone G (3), together with nine known compounds (4-12) were isolated from the EtOAc extract of the marine-derived fungus Aspergillus sp . WHUF03110. The structures of 1-3 were determined by spectroscopic analysis, and comparison with literature data. Most of these isolated compounds were evaluated for their antimicrobial activities against ten Gram-negative and seven Gram-positive bacteria, Mycobacterium smegmatis ATCC 607, Candida albicans ATCC SC5314, and C. albicans YY-1-4. Compound 10 displayed strong antibacterial activity against five Gram-positive bacteria ( Bacillus subtilis 168, Staphylococcus aureus ATCC25923, S. aureus NEWMAN, S. aureus USA300, S. aureus NRS 271) with MIC values ranging from 1.0 to 2.0 μg/mL, and displayed moderate antibacterial activity against four Gram-negative bacteria ( Helicobacter pylori 26695, H. pylori G27, H. pylori 159, H. pylori 129) and M. smegmatis ATCC 607 with a MIC value of 8.0 μg/mL.

Mushroom Species Stereum hirsutum as Natural Source of Phenolics and Fatty Acids as Antioxidants and Acetylcholinesterase Inhibitors

Many lignicolous mushroom species are used as a food supplement and may represent an alternative treatment of Alzheimer's disease (AD). This study aimed to evaluate acetylcholinesterase inhibition (AChEI) of Stereum hirsutum together with antioxidant activity (AO) and cytotoxic activity against HepG2 cells. Different extracts (water, ethanol, methanol, polysaccharide) were analyzed, with respect to their mineral composition and chemical content. Ethanol extract was the most potent in AChEI (98.44 %) and demonstrated cytotoxic activity (91.96 % at 900.00 μg/mL), while the highest AO was demonstrated for polar extracts (methanol and water) as well. These activities may be attributed to determined phenolics (hydroxybenzoic and quinic acid) and fatty acids (FA), while biflavonoid amentoflavone may be responsible for cytotoxic activity. The most prevalent FA was linoleic (40.00 %) and the domination of unsaturated FA (UFA) (71.91 %) over saturated (26.96 %) was observed. This is the first report of AChEI of S. hirsutum extracts and first detection of amentoflavone. Due to high amount of UFA and well-expressed AChEI, this species can be considered as a potent food supplement in the palliative therapy of AD.

Bioactive Phenolic Compounds of Two Medicinal Mushroom Species Trametes versicolor and Stereum subtomentosum as Antioxidant and Antiproliferative Agents

Medicinal mushrooms have tremendous potential in production of bioactive compounds with diverse bioactivities while the biochemical potential of some specific mushroom strains (autochthonous for the region) in production of specific bioactive agents may be of the main importance in a continuous search for novel strains with supreme activities all over the world. In this study, the ethanolic (EtOH) and water (H₂ O) extracts of wild-growing polypore mushroom species were investigated: Trametes versicolor (L.) Lloyd and Stereum subtomentosum Pouzar. This study was designed to determine total phenol (TP), flavonoid (TF) and protein content (TPR) as well as LC/MS/MS phenolic profile related to in vitro antioxidant, antiproliferative (MTT assay) (AP) and DNA fragmentation properties. The H₂ O extracts expressed better antioxidant scavenging potential than EtOH showing the highest activity for the T. versicolor (IC₅₀ =5.6 μg/mL, IC₅₀ =0.6 μg/mL for DPPH^. and OH^. , respectively) while O₂ ^.- activity achieved the best activity for S. subtomentosum (IC₅₀ =4.1 μg/mL). In contrary, the highest AP activity was obtained for the EtOH extracts of S. subtomentosum (IC₅₀ =141.1 μg/mL). The EtOH extracts of both species showed the highest TP, TF and TPR content. Obtained results of DNA degradation indicate genotoxicity potential of the extracts at high concentration. The LC/MS/MS detection showed that the majority of analyzed extracts contained phenolic acids, p-hydroxybenzoic and protocatechuic acid. The obtained results suggest that analyzed medicinal mushroom species, T. versicolor and S. subtomentosum, could be of potential interest as new sources of strong natural antioxidants as well as antiproliferative agents in the future.

In Depth Natural Product Discovery from the Basidiomycetes Stereum Species

Natural metabolites from microorganisms play significant roles in the discovery of drugs, both for disease treatments in humans, and applications in agriculture. The Basidiomycetes Stereum genus has been a source of such bioactive compounds. Here we report on the structures and activities of secondary metabolites from Stereum. Their structural types include sesquiterpenoids, polyketides, vibralactones, triterpenoids, sterols, carboxylic acids and saccharides. Most of them showed biological activities including cytotoxic, antibacterial, antifungal, antiviral, radical scavenging activity, autophagy inducing activity, inhibiting pancreatic lipase against malarial parasite, nematocidal and so on. The syntheses of some metabolites have been studied. In this review, 238 secondary metabolites from 10 known species and various unidentified species of Stereum were summarized over the last seven decades.

Pyoluteorin induces cell cycle arrest and apoptosis in human triple-negative breast cancer cells MDA-MB-231

Objectives

To screen the cytotoxic activity of six secondary metabolites isolated from soil fungus Aspergillus niger. Importantly, to investigate the mechanism that pyoluteorin induced human triple-negative breast cancer MDA-MB-231 cells apoptosis in vitro.

Methods

The cell viability assay was tested with CTG assay. Cell cycle, apoptosis and intracellular reactive oxygen species (ROS) production assay were tested with flow cytometry. Additionally, intracellular ROS production assay and mitochondrial membrane potential assay were determined with laser scanning confocal microscopy. The expression of apoptosis-related proteins was determined with Western blot.

Key findings

Pyoluteorin displayed significantly selective cytotoxicity against human triple-negative breast cancer MDA-MB-231 cells (IC50 = 0.97 µm) with low toxicity against human breast epithelial cell MCF-10A. It was found that pyoluteorin could arrest MDA-MB-231 cells cycle at G2/M phase and induce cell apoptosis. Further experiments demonstrated that the apoptosis-inducing effect of pyoluteorin was related to reduction of mitochondrial membrane potential, accumulation of ROS and change of apoptosis-related protein expressions.

Conclusion

Our studies revealed that pyoluteorin had potent proliferation inhibition against MDA-MB-231 cells through arresting cell cycle at G2/M phase and inducing caspase-3-dependent apoptosis by mitochondrial pathway, implying that pyoluteorin may be a potential lead compound for drug discovery of human triple-negative breast cancer.

Formation of Decatrienones with a Pineapple-like Aroma from 1-13C-Acetate by Cell Cultures of the Birch Polypore, Fomitopsis betulina

During submerged cultivation, the edible basidiomycete Fomitopsis betulina (previously Piptoporus betulinus) developed a fruity odor, strongly reminding of pineapple. Olfactometric analysis showed that this impression was mainly caused by the two (5E/Z,7E,9)-decatrien-2-ones. At the time of maximum concentration on the 5th day, the (5E/5Z)-ratio was 94:6. Three hypotheses were experimentally examined to shed light onto the genesis of the uncommon volatiles: first, an indirect effect of agro-industrial side-streams, such as cabbage cuttings, supporting good growth; second, an unsaturated odd-numbered fatty acid precursor; and third, a polyketide-like pathway. In the presence of 1-¹³C- or 2-¹³C-acetate up to five acetates were incorporated into the molecular ions of the C10-body. Addition of 1-¹³C-pyruvate or 1-¹³C-lactate did not confirm an odd-numbered starter of the polyketide chain. None of the methylketones was found in pineapple or any other food before.

Sarocladione, a unique 5,10:8,9-diseco-steroid from the deep-sea-derived fungusSarocladium kiliense

Sarocladione was isolated from the deep-sea-derived fungusSarocladium kilienseas the first example of a 5,10:8,9-diseco-steroid.

Chemical Constituents of the Marine-Derived Fungus Aspergillus sp. SCS-KFD66

Five new compounds named asperpenes A-C (1–3), 12,13-dedihydroversiol (4), and methyl 6-oxo-3,6-dihydro-2H-pyran-4-carboxylate (5), along with 10 known compounds (6–15), were isolated from the fermentation broth of Aspergillus sp. SCS-KFD66 associated with a bivalve mollusk, Sanguinolaria chinensis, collected from Haikou Bay, China. The structures of the compounds, including the absolute configurations of their stereogenic carbons, were unambiguously determined by spectroscopic data, single-crystal X-ray diffraction analysis, and electronic circular dichroism (ECD) spectral analysis, along with quantum ECD calculations. The growth inhibitory activity of the compounds against four pathogenic bacterial (Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538, Listeria monocytogenes ATCC 1911, and Bacillus subtilis ATCC 6633), their enzyme inhibitory activities against acetylcholinesterase and α-glucosidase, and their DPPH radical scavenging activity were evaluated.

Two novel bioactive sulfated guaiane sesquiterpenoid salt alkaloids from the aerial parts of Scorzonera divaricata

Extracts of the aerial parts of Scorzonera divaricata afforded sulfoscorzonin D (1) and sulfoscorzonin E (2), two novel pyrrolidine inner salt alkaloids with a sulfated guaiane sesquiterpene lactone nucleus, along with 22 known compounds. Especially, sulfoscorzonin D containing a unusual monoterpene moiety is very rare. The structures of new compounds were established using spectroscopic analysis including one- and two-dimensional NMR and HRESIMS. The cytotoxicities of compounds 1-4 and 10 against three tumor cell lines (K562, Hela, and HepG2) were evaluated using the MTT assay. Compounds 2 and 10 exhibited moderate cytotoxic activity. The biological properties of 1-3, 5-8, 10-14, and 16-24, were screened against nine different gram-positive and gram-negative bacteria. Compounds 1, 5-8, 10, and 18, showed potent antibacterial activities.

CHEMICAL COMPOUNDS STUDIED IN THIS ARTICLE

Glucozaluzanin C (PubChem CID: 442320); 1β,4α-dihydroxy-5α,6β,7α,11βH-eudermn-12; 6-olide (CID: 11119093); oleanolic acid (CID: 10494); lup-20(29)-ene-3β,28-diol (CID: 72326); (22E)-5α,8α-epidioxyergosta-6,22-dien-3β-ol (CID: 5469431); ergosta-3β,5α, 6β-trialcohol (CID: 44558918); stigma-5-en-3-O-β-glucoside (CID: 5742590); vomifoliol (CID: 12444927); trans-caffeic acid (CID: 689043); trans-p-hydroxy coumaric acid (CID: 637542); 4-hydroxy-3-methoxyphenyl ferulate (CID: 11500646); 7,3',4'-trihydroxyflavonol (CID: 5281614); tricin (ID: 5281702); luteolin (CID: 5280445); diosmetin (CID: 5281612); 5,7-dihydroxy-8-methoxyflavone (CID: 5281703); 5,7-dihydroxy-6-methoxyflavone (CID: 5320315); methyl-3,4-dihydroxy benzoate (CID: 287064); m-hydroxy benzoic acid (CID: 7420); 7-hydroxy-coumarin (CID: 5281426); and scopoletin (CID: 5280460).

Fomitopsis betulina (formerly Piptoporus betulinus): the Iceman's polypore fungus with modern biotechnological potential

Higher Basidiomycota have been used in natural medicine throughout the world for centuries. One of such fungi is Fomitopsis betulina (formerly Piptoporus betulinus), which causes brown rot of birch wood. Annual white to brownish fruiting bodies of the species can be found on trees in the northern hemisphere but F. betulina can also be cultured as a mycelium and fruiting body. The fungus has a long tradition of being applied in folk medicine as an antimicrobial, anticancer, and anti-inflammatory agent. Probably due to the curative properties, pieces of its fruiting body were carried by Ötzi the Iceman. Modern research confirms the health-promoting benefits of F. betulina. Pharmacological studies have provided evidence supporting the antibacterial, anti-parasitic, antiviral, anti-inflammatory, anticancer, neuroprotective, and immunomodulating activities of F. betulina preparations. Biologically active compounds such as triterpenoids have been isolated. The mushroom is also a reservoir of valuable enzymes and other substances such as cell wall (1→3)-α-D-glucan which can be used for induction of microbial enzymes degrading cariogenic dental biofilm. In conclusion, F. betulina can be considered as a promising source for the development of new products for healthcare and other biotechnological uses.

Medicinal properties of fungi occurring on Betula sp. trees. A review

The article presents the chemical costituents and pharmacological properties of polyporoid fungi found on birch, namely Piptoporus betulinus, Inonotus obliquus, Lenzites betulina, Fomes fomentarius, and Trametes versicolor. The in vitro and in vivo studies on the effect of different extracts from above-mentioned fungi on the human organism shown anti-cancer, anti-inflammatory, antiviral, antibacterial and immunostimulant activity, conditioned by the presence of such compounds as polysaccharides, polyphenols or terpenes. These fungi are commonly found in Poland and may superbly compete with Ganoderma lucidum (Reishi) or Lentinula edodes (Shitake) used in Asia for medicinal purposes.

α-Glucosidase Inhibitors from the Fungus Aspergillus terreus 3.05358

One new diketopiperazine alkaloid amauromine B (1), along with three known meroterpenoids, austalide B (2), austalides N and O (3 and 4), and two known steroids (5 and 6), was isolated and identified from the culture broth of the fungus Aspergillus terreus 3.05358. Their structures were elucidated by extensive spectroscopic techniques, including 2D-NMR and MS analysis, the absolute configuration of 1 was unambiguously established by single crystal X-ray diffraction analysis. All the isolates were evaluated for their inhibitory effects on α-glucosidase. Amauromine B (1) and austalide N (3) exhibited more potent α-glucosidase inhibitory activities than the positive control acarbose.

European medicinal polypores--a modern view on traditional uses

ETHNOPHARMACOLOGICAL RELEVANCE

In particular five polypore species, i.e. Laetiporus sulphureus, Fomes fomentarius, Fomitopsis pinicola, Piptoporus betulinus, and Laricifomes officinalis, have been widely used in central European folk medicines for the treatment of various diseases, e.g. dysmenorrhoea, haemorrhoids, bladder disorders, pyretic diseases, treatment of coughs, cancer, and rheumatism. Prehistoric artefacts going back to over 5000 years underline the long tradition of using polypores for various applications ranging from food or tinder material to medicinal-spiritual uses as witnessed by two polypore species found among items of Ötzi, the Iceman. The present paper reviews the traditional uses, phytochemistry, and biological activity of the five mentioned polypores.

MATERIALS AND METHODS

All available information on the selected polypore taxa used in traditional folk medicine was collected through evaluation of literature in libraries and searches in online databases using SciFinder and Web of Knowledge.

RESULTS

Mycochemical studies report the presence of many primary (e.g. polysaccharides) and secondary metabolites (e.g. triterpenes). Crude extracts and isolated compounds show a wide spectrum of biological properties, such as anti-inflammatory, cytotoxic, and antimicrobial activities.

CONCLUSIONS

The investigated polypores possess a longstanding ethnomycological tradition in Europe. Here, we compile biological results which highlight their therapeutic value. Moreover, this work provides a solid base for further investigations on a molecular level, both compound- and target-wise.