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Three previously undescribed triquinane type sesquiterpenoids, antrodiellins A‒C (1‒3), together with three known analogues 4‒6, were isolated from wild fungus Antrodiella albocinnamomea. Their structures were elucidated by means of spectroscopic analysis and single crystal X-ray diffraction. Compounds 3 and 4 exhibited weak inhibitions against Staphylococcus aureus with MIC values of 128 and 64 μg/mL, respectively.

Three previously undescribed compounds including two ergosterols, diaporthins A and B (1 and 2), and a pyrrolidinone derivative, (±)-diaporthin C (3), together with three known compounds 4‒6, were isolated from cultures of kiwi-associated fungus Diaporthe phragmitis. The racemic 3 was further separated into pure enantiomers. Their structures with absolute configurations were elucidated by means of spectroscopic analysis, as well as single crystal X-ray diffraction analysis and electronic circular dichroism (ECD) calculations. Compounds 5 and 6 showed antibacterial activity against Pseudomonas syringae pv. actinidae with MIC values of 25 and 6.25 μg/mL, respectively.

(-)-5-Methylmellein (1) and its new dimer (2) were isolated from cultures of the basidiomycete Inonotus sinensis. Their structures were elucidated on the basis of extensive spectroscopic methods including UV, IR, HR-EI-MS, 1D NMR and 2D NMR. The structure of Compound 2 was determined by single-crystal X-ray crystallographic analysis. Compound 2 was tested for the cytotoxicities against five human cancer cell lines.

Xylongoic acids A–C, three isopimarane diterpene derivatives were isolated from the rice cultures of Xylaria longipes HFG1018, a fungicolous fungus isolated from the fruiting bodies of the wood-decay and medicinal fungus Fomitopsis betulina. The structures of the isolated compounds were determined by extensive analysis of NMR and HRESIMS data.

Four polyketide-amino acid derivatives, pardinumones A-D (1-4), were isolated from the wild mushroom Tricholoma pardinum. Their structures together with absolute configurations were characterized by means of spectroscopic data analyses, as well as calculated electronic circular dichroism (ECD) and NMR with sorted training set (STS) protocol analysis. Compounds 1-4 exhibited antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli with MIC values in the range of 6.25-50 μg/mL.

Two new homosioflavonoids, ophiopogonanone I (1) and methylophiopogonanone C (2) were isolated from the tuberous roots of Ophiopogon japonicus. Their structures were elucidated on the basis of extensive spectroscopic analyses. The absolute configuration of compounds 1 and 2 were assigned on the basis of CD method. In addition, compounds 1–2 were tested for their cytotoxic activities against HL-60, SMMC-7721, and MCF-7 human cancer cell lines, and compound 2 showed significant cytotoxic activity against HL-60 cell line with IC50 value of 14.42 μM.

Cancer is the main cause of death, and the emergence of resistance by cancer cells towards existing anticancer agents is one of the major problems for effective chemotherapy, creating a great demand for the development of novel anticancer drugs. Coumarins, abundantly found in nature, constitute an important class of pharmacological agents possessing physiological activities. The mechanism investigations elucidated that coumarins could lead to self-programmed cancer cell death (apoptosis) via different mechanisms; thereby coumarin-based derivatives possess potential activity against various forms of cancers, including drug-resistant, even multidrug-resistant cancers. This review article describes the recent progress in the discovery, structural modification, structure-activity relationship, and mechanism of action studies of coumarin-based derivatives with potential activity against drug-resistant cancers, covering articles published between 2010 and 2020.

Two new alkaloids, phranisines A–B (1–2), along with two known compounds, N-p-Coumaroyl serotonin (3) and N-p-coumaroyl-tryptamine (4), were isolated from the roots of Phragmites australis. The structures of 1–4 were established on the basis of extensive spectroscopic. The absolute configuration of compounds 1–2 were identified through quantum-chemical electronic circular dichroism (ECD) calculation compared with their experimental CD. All the isolated compounds were tested for their cytotoxic activities against HeLa and MCF-7 human cancer cell lines, and compounds 2–4 showed moderate cytotoxic activities against HeLa cell lines with IC50 values ranging from 13.2 to 18.6 μM.

Exercise-induced benefits are being increasingly recognized in promoting health and preventing diseases. However, initial adaption to exercise response can have different effects on cells, including an increase in the formation of oxidants and inflammatory mediators that ultimately leads to oxidative stress, but this scenario depends on the exercise type and intensity and training status of the individual. Therefore, we aimed to understand the effect of different types of exercise on oxidative stress. Indeed, exercise-induced minimum oxidative stress is required for regulating signaling pathways. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, a search for relevant articles was carried out on PubMed/Medline, ISI Web of Science, and Google Scholar using a broad range of synonyms such as oxidants, reactive oxygen species (ROS), oxidative stress, exercise, physical training, aerobic exercise, and strength exercise until 2019. This study selected a total of 18 articles for assessing the oxidative damage using various parameters such as malondialdehyde (MDA), protein carbonyl (PCO), and F1-isoprostanes and enzymatic antioxidants. We observed that any type of exercise can increase the oxidative damage in an exercise type and intensity manner. Further, the training status of the individual and specific oxidative damage marker plays a crucial role in predicting earlier oxidative damage in the exercise condition. However, some of the studies that we included for review did not perform follow-up evaluations. Therefore, follow-up programs using larger numbers need to be performed to confirm our findings.

Melodinines Y1–Y4 (1–4), four undescribed alkaloids were isolated from Melodinus henryi. Their structures were elucidated by extensive NMR, mass spectroscopic analyses, theoretical NMR and electronic circular dichroism (ECD) calculations. Compounds 1 and 2 are the first examples of bisindole alkaloids possessing an eburnamine–leuconoxine combination. Compound 3 is a rare 2,3-seco pleiocarpamine type monoterpene indole alkaloid. Compound 1 showed cytotoxic activities against six human cancer cell lines with IC50 values of 0.5–15.2 μM.

Four rare 3-decalinoyltetramic acid derivatives, zofielliamides A–D (1–4), were obtained from cultures of kiwi-associated fungus Zopfiella sp. Their structures with absolute configurations were established by extensive spectroscopic methods and single crystal X-ray diffraction. The compounds possessed rare pentacyclic systems that might derive from a polyene precursor via [4 + 2] intramolecular Diels–Alder reactions. Compounds 1, 2, and 4 showed antibacterial activity against plant pathogen Pseudomonas syringae with MIC values of 64, 32, and 64 μg mL−1, respectively.

Ochracines F–L (1–7), seven previously undescribed chamigrane and cadinane sesquiterpenoids, together with four known chamigranes were isolated from cultures of the wood-decaying fungus Steccherinum ochraceum HFG119. Ochracines F–L were structurally characterized by extensive analysis of HRMS and NMR spectroscopic data. The relative configurations were assigned through a combination of NOE correlations and J-based configuration analysis (JBCA), while the absolute configurations were determined by X-ray single-crystal diffraction, and calculated methods (ECD, [α], 13C NMR). All the new isolates were evaluated for their cytotoxicity against five human cancer cell lines HL-60, SMMC-7721, A549, MCF-7, and SW-480, and inhibitory activity on NO production in RAW 264.7 macrophages.

Two undescribed Tricholoma triterpenoids, namely tricholopardins C (1) and D (2), were isolated from the wild mushroom Tricholoma pardinum. Their structures with absolute configurations were elucidated by spectroscopic methods, as well as the single crystal X-ray diffraction. Compounds 1 and 2 were further obtained by chemical conversions from the known analogues. Compound 1 showed significant cytotoxicity to MCF-7 and Hela cell lines with IC50 values of 4.7 μM and 9.7 μM, respectively. Its mechanism of inducing MCF-7 cell apoptosis was studied briefly. Graphical Abstract

An efficient [3 + 2] cycloaddition of in situ generated nitrile imines with enamides has been established. A wide range of functionalized pyrazoline derivatives (53 examples) were obtained in moderate to good yields (up to 96%) under very mild conditions. This protocol features broad substrate scope, good functional group tolerance, and operational simplicity. Practical transformation of the products into useful pyrazoles via a one-pot process and the scalability of this protocol highlight the utility of this synthetic methodology.

A visible-light-induced and iron-catalyzed oxidative radical addition/cyclization cascade reaction of N-(o-cyanoaryl)acrylamides with dimethyl sulfoxide has been developed. The method exhibits a wide substrate scope and an excellent functional-group tolerance, thus providing an efficient and convenient access to a variety of methylated quinoline-2,4-diones.

Seven new merosesquiterpenoids, trichothecrotocins D-J (1-7), two new trichothecene sesquiterpenoids, trichothecrotocins K (12) and L (13), and six known compounds (8-11, 14, and 15), were isolated from a potato-associated fungus, Trichothecium crotocinigenum. Compounds 5 and 6 were racemates which were further separated as pure enantiomers. Structures together with absolute configurations were established by extensive spectroscopic analysis, as well as quantum chemistry calculations on ECD and optical rotations. Compounds 1-4 are rare meroterpenoids featuring a seco-phenyl group, while 1 and 2 possessed a novel 6-6/5 fused ring system. Compounds 1-4, 8, 11, and 12 showed antifungal activity against four plant pathogens with MIC values of 8-128 μg/mL. It is suggested that the meroterpenoids produced by T. crotocinigenum may play an important role in the antifungal property of the fungus, thereby protecting the host plant, i.e., potato.

Conosiligins A-D (1-4), four ring-rearranged sesquiterpenoids, were isolated from cultures of the basidiomycete Conocybe siliginea. Their structures and absolute configurations were determined by detailed spectroscopic analyses and equivalent circulating density (ECD) calculations. Compounds 1 and 2 possess a 5/8-fused ring system, while 3 has a 5/6-fused backbone conjugated with a γ-lactone. Compound 4 is a 5,6-seco tremulane derivative with the loss of a skeletal carbon, featuring a tetracyclic system involving a pyranone moiety. Compounds 3 and 4 inhibited Con A-induced T cell proliferation with IC50 values of 12.3 and 6.6 μM, respectively.

To comprehensively understand the chemical constituents of the edible mushroom Agrocybe salicacola and their biological functions, a phytochemical separation of the cultural broth of A. salicacola led to the isolation of four new illudane sesquiterpenoids, agrocybins H-K (1-4), along with 10 known analogues (5-14). Compounds 2-4 were racemates of which 2 and 3 were further separated into single enantiomers as 2a/2b and 3a/3b. All new structures with absolute configurations were elucidated on the basis of an extensive spectroscopic analysis and quantum chemistry calculations. Compound 1 possesses a new carbon skeleton that might be derived from the protoilludane backbone. Compounds 1, 5, 8, and 9 show a certain degree of cytotoxicity to five human cancer cell lines. Compound 1 shows a mild inhibitory effect on nitric oxide production with an IC50 value of 31.4 μM. It is concluded that A. salicacola is rich in illudin derivatives with potential bioactivity prospects, which would make A. salicacola a good material of medicine and food homology.

GIAO 13C NMR calculation plays important roles in structural assignment for small organic molecules. Especially, higher accuracy and confidence are required for the structural assignation of complex organic molecules. In this GIAO 13C NMR calculation strategy, carbons were sorted according to their type of hybridization, radii of solvation cavity, or solvent interactions. The calculated shielding tensors of carbons in each sorted training set were linear-regressed with experimental data separately, and the obtained linear parameters were used to convert calculated shielding tensors into calculated chemical shifts. This approach shows significantly improved accuracy, especially for sp2 carbons, compared to conventional GIAO 13C NMR calculation protocols. A statistic-based probability algorithm was proposed to quantify the reliability of structural assignation. With empirical linear parameters for three commonly used NMR solvents as well as an easy-to-use script and a spreadsheet, this 13C NMR calculation protocol provides a useful tool for structural validation or assignation of ambiguous organic structures.

Three undescribed bisabolane sesquiterpenoids, zopfiellins A–C (1‒3), and one new α-pyrone derivative, zofiellone (4), have been isolated from cultures of the endophytic fungus Zopfiella sp. Compound 2 is a rare trinor-bisabolane sesquiterpenoid and 3 has an unusual aromatic core. Compounds 3 and 4 possess mild cytotoxicities against three human cancer cell lines with a range of IC50 values from 12.3–27.3 μM.

Two skeletally novel tetracyclic diterpenoids, psathyrins A (1) and B (2), have been characterized from cultures of the basidiomycete Psathyrella candolleana. Their structures including absolute co...

Eight previously undescribed sesquiterpenoids, tremutins A-H (1-8), together with three known ones (9-11), were isolated from cultures of the basidiomycetes Irpex lacteus. Structures of the new compounds together with absolute configurations were elucidated on the basis of extensive spectroscopic methods, as well as single-crystal X-ray diffractions and equivalent circulating density calculations. Compounds 1 and 2 possess an unusual 6/7-fused ring system that might be derived from a tremulane framework. Compounds 3-7 and 9-11 are tremulane sesquiterpenoids of which 4 and 5 are the first tremulane examples with a 1,2-epoxy moiety to be reported. Compounds 6, 7, 10, and 11 possess weak activities to several human cancer cell lines. Compound 8 shows a weak inhibitory effect on NO production with a half maximal inhibitory concentration (IC50) value of 22.7 μM. Compound 1 inhibits the lipopolysaccharide (LPS)-induced proliferation of B lymphocyte cells with an IC50 value of 22.4 μM, while 2 inhibits concanavalin A (Con A)-induced T cell proliferation and LPS-induced B lymphocyte cell proliferation with IC50 values of 16.7 and 13.6 μM, respectively.

A new irlactane-type, namely irlactin K (1), and 22 tremulane-type sesquiterpenes including fourteen previously undescribed ones, namely irpexolactins A–N (2–15), and a known irlactane-type sesquiterpenoid, were isolated from the fermentation broth of the medicinal fungus Irpex lacteus HFG1102. The structures of all the isolates were characterized by extensive spectroscopic methods, including 1D and 2D NMR and MS spectroscopic analysis. The absolute configurations of irlactin K and the known compound conocenol B (20) were established by single-crystal X-ray diffraction analysis. The vasorelaxant effects of irlactin K (1), irpexolactins A (2), C (4), K (12), and irlactam (22) were evaluated. Graphic Abstract

Objective To assess the defatting efficacy of high pressure washing and gradient alcohol and biomechanical properties of defatted bone. Methods Fresh cancellous bone was obtained from the femoral condyle and divided into six groups according to different defatting treatments, which were: high pressure washing for 10 s (10S group), 20 s (20S group), and 30 s (30S group), gradient alcohol immersion (Alcohol group), acetone immersion (Acetone group), and non-defatted (Fresh group). The appearance of six groups was observed, and the appearance of defatted bone and fresh bone was compared. The residual lipid content and infrared spectrum were used to compare the efficacy of defatting, the DNA content was used to compare the cell content after defatting, and the maximum stress and elastic modulus were used to compare the effects of defatting treatment on biomechanical properties. Results The fresh bone was yellow and the pores contained a lot of fat. The defatted bone was white and the porous network was clear. There was no difference in residual lipid content among the three groups with high pressure washing (1.45% ± 0.16%, 1.40% ± 0.13%, and 1.46% ± 0.11%, respectively) (P = 0.828). There was no difference in residual lipid content among the 10S, alcohol, and acetone groups (1.45% ± 0.16%, 1.28% ± 0.07%, and 1.13% ± 0.22%, respectively) (P = 0.125). Infrared spectra showed that the fat content of the five defatting groups was significantly lower than that of the fresh group. There was no difference in residual lipid content among the three groups with high pressure washing (4.53 ± 0.23 ug/mL, 4.61 ± 0.18 ug/mL, and 4.66 ± 0.25 ug/mL, respectively) (P = 0.645). There was no difference in residual lipid content among the 10S, alcohol, and acetone groups (4.53 ± 0.23 ug/mL, 4.29 ± 0.24 ug/mL, and 4.27 ± 0.29 ug/mL, respectively) (P = 0.247). The maximum stress of the bone decreased significantly with the increase of the washing time (9.95 ± 0.31 Mpa, 9.07 ± 0.45 Mpa, and 8.17 ± 0.35 Mpa, respectively) (P = 0.003). The elastic modulus of the bone decreased significantly with the increase of the washing time (116.40 ± 3.54 Mpa, 106.10 ± 5.29 Mpa, and 95.63 ± 4.08 Mpa, respectively) (P = 0.003). There was no statistical difference in the maximum stress between the fresh group, the 10S group, the alcohol group, and the acetone group (10.09 ± 0.67 Mpa, 9.95 ± 0.31 Mpa, 10.11 ± 0.07 Mpa, and 10.09 ± 0.39 Mpa, respectively) (P = 0.963). There was no statistical difference in the maximum stress between the fresh group, the 10S group, the alcohol group and the acetone group (119.93 ± 4.94 Mpa, 116.40 ± 3.54 Mpa, 118.27 ± 0.85 Mpa, 118.10 ± 4.52 Mpa, respectively) (P = 0.737). Conclusion The defatting efficiency was satisfactory at a time of 10 s under high pressure washing. In terms of defatting efficiency and its effect on biomechanical properties of bone, high pressure washing and gradient alcohol were similar to conventional acetone solvent extraction defatting.

Two new tremulane-type sesquiterpenes, irlactin L (1) and irlactin M (2) were isolated from cultures of the fungus Irpex lacteus, together with one known compound, 6-hydroxy-2,6-dimethyloct-7-enoic...

Eighteen new nor-isopimarane diterpenes, xylarinorditerpenes A-R (1-18), along with two previously reported compounds, 14α,16-epoxy-18-norisopimar-7-en-4α-ol (19) and the labdane-type diterpene agatadiol (20), were isolated from cultures of the fungicolous fungus Xylaria longipes HFG1018 isolated from the wood-rotting basidiomycete Fomitopsis betulinus. The structure elucidation and relative configuration assignments of 1-18 were accomplished by interpretation of spectroscopic data and through computational methods. The absolute configurations of 1, 4, and 16 were determined by single-crystal X-ray diffraction. Compounds 1-16 possess an 18- or 19-nor-isopimarane skeleton, and compounds 17 and 18 possess an 18,19-dinor-isopimarane skeleton. Compounds 2-5, 9, 14, 19, and 20 showed immunosuppressive activity but were devoid of cytotoxicity against the cell proliferation by concanavalin A-induced T lymphocytes and lipopolysaccharide-induced B lymphocytes, with IC50 values varying from 1.0 to 27.2 μM and from 16.1 to 51.8 μM, respectively.

Kiwi (Actinidia chinensis) plants are severely destroyed by canker disease which is caused by the bacterium Pseudomonas syringae pv. actinidiae (Psa). This program tries to find anti-Psa agents among secondary metabolites of endophytic fungi from kiwi plant itself. The chemical investigation on one kiwi endophytic fungi, Fusarium tricinctum, resulted in the isolation of nine new imidazole alkaloids, fusaritricines A-I (1–9) together with seven known analogues (10–16). The structures of new compounds were established by extensive spectroscopic methods. Compounds 2, 3, 9, and 13 showed good antibacterial activity against Psa with MIC values between 25 and 50 μg/mL. It is suggested that imidazole alkaloids should be potential anti-Psa agents.

Naringin is a kind of multi-source food additive which has been explored broadly for its various biological activities and therapeutic potential. In the present study, the protective effect and mechanism of naringin on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice were investigated. The results showed that naringin significantly alleviated DSS-induced colitis symptoms, including disease activity index (DAI), colon length shortening, and colon pathological damage. The tissue and serum secretion of inflammatory cytokines, as well as the oxidative stress, were decreased accordingly upon naringin intervention. Naringin also decreased the proteins involved in inflammation and increased the expression of tight junction (TJ) proteins. Moreover, naringin increased the relative abundance of Firmicutes/Bacteroides and reduced the content of Proteobacteria to improve the intestinal flora disorder caused by DSS, which promotes the intestinal health of mice. It was concluded that naringin can significantly ameliorate the pathogenic symptoms of UC through inhibiting inflammatory response and regulating intestinal microbiota, which might be a promising natural therapeutic agent for the dietary treatment of UC and the improvement of intestinal symbiosis.

In our continuous search for antibacterial agents against Pseudomonas syringae pv. actinidiae (Psa) from kiwi-associated fungi, two pairs of epimeric cytochalasins, zopfiellasins A–D (1–4), were characterized from the fungus Zopfiella sp. The structures were established on the basis of spectroscopic data analysis, while the absolute configurations were determined by single-crystal X-ray diffraction. Compounds 1 and 3 exhibited antibacterial activity against Psa with MIC values of 25 and 50 μg/mL, respectively. This is the first report of anti-Psa activity of cytochalasin derivatives.

Three undescribed lanostane triterpenoids, together with twenty-one known compounds, were isolated from artificially cultivated fruiting bodies of the basidiomycete Ganoderma sichuanense. The absolute configuration at C-25 of ganoderic acid A and its derivatives was determined to be 25R by application of the phenylglycine methyl ester (PGME) method. Among the isolated compounds, ganoderiol F exhibited the most potent activity against Mycobacterium tuberculosis H37Ra with an MIC value of 0.781 μg/ml.

A quaternary carbon center containing an oxindole motif is constructed via NHC-catalyzed transition-metal and aldehyde-free intermolecular Heck-type alkyl radical addition initiated annulation. This redox-neutral protocol also features a simple procedure, broad substrate scope, good functional group tolerance and could be smoothly amplified to a gram scale. The mechanism study shows that the reaction possibly undergoes two folds of SET processes with an NHC radical cation intermediate involved.

A new tremulane sesquiterpene lactone, named irlactin K (1), was isolated from the culture broth of the basidiomycete Irpex lacteus. The structure of the new compound was established through extensive spectroscopic analyses. The compound was tested for its cytotoxicity against five human cancer cell lines and for its inhibitory activity against isozymes of 11β-hydroxysteroid dehydrogenases.

A new isopimarane diterpenoid, inonotolide D (1), was isolated from cultures of the basidiomycetes Inonotus sinensis. The new structure was elucidated on the basis of extensive spectroscopic studies. The compound was evaluated for its cytotoxicities against five human cancer cell lines.

Two new compounds, daedatrin K (1) and 2-hydroxy-1-(5-(hydroxymethyl)furan-2-yl)propan-1-one (2), were isolated from cultures of the basidiomycetes Daedaleopsis tricolor. The new structures were el...

A cytochalasan, xylarichalasin A, was obtained from the endophytic fungus Xylaria cf. curta harbored in Solanum tuberosum. Its structure was elucidated by comprehensive spectroscopic methods including HRESIMS, 1D/2D NMR, and residual dipolar coupling analysis as well as quantum chemistry calculations including DFT GIAO 13C NMR and ECD calculation. It has an unprecedented 6/7/5/6/6/6 fused polycyclic structure. In bioassay, xylarichalasin A showed cytotoxicity against human cancer cell lines with IC50 value ranging from 6.3-17.3 μM.

Two previously undescribed cadinane-type sesquiterpenoids, rigidoporones A and B (1 and 2), along with an undescribed racemic indolizine alkaloid, (±)-rigidoporine A (3), were isolated from the rice fermentation of the wood-decay fungus Rigidoporus microporus. The structures of the compounds were established by extensive spectroscopic methods, including 1D & 2D NMR and HRMS spectroscopic analysis. Compounds 1 and 3 were evaluated for their inhibitory activity on NO production in murine monocytic RAW264.7 macrophages (IC50 > 25 μM).

The unprecedented 1,3-dipolar cycloaddition of 1,3,5-triazinanes and aziridines has been described. With readily available starting material, this method offers efficient access to a wide range of functionalized imidazolidine derivatives in moderate to good yields (up to 92%) under mild conditions. Preliminary mechanistic investigations show that the ring opened zwitterionic pathway product dominated over the second-order nucleophilic substitution-like product. This protocol is very promising because the reaction is scalable, and gives versatile transformation of the products into other functionalized imidazolidines.

Structurally unique thiopyranodipyridine alkaloids xylaridines C (1) and D (2) were isolated from the fungus Xylaria longipes. Their structures were established by comprehensive spectroscopic analysis combined with single-crystal X-ray diffraction and electron-capture detection (ECD) calculations. Compound 1 possesses two piperidine moieties fused with a centered thiopyran ring, while compound 2 is a dimer of 1. Compound 1 was resoluted into optical pure enatiomers (+)-1 and (-)-1 by chiral HPLC. Moreover, compound 2 was resoluted into an optically pure compound (+)-2 and a mixture of (-)-2 and meso-2. Plausible biosynthetic pathways of compounds 1 and 2 are proposed.

Hypoglycemic drugs such as metformin increase glucose uptake and utilization by peripheral tissues to maintain glucose homeostasis, and the AMP-activated protein kinase (AMPK) signaling pathway is an important component of this pharmacological activity. Liver kinase B1 (LKB1) acts as a kinase upstream of AMPK and plays an important regulatory role in glucose metabolism. In recent years, as a tumor suppressor, LKB1's antitumor activity has been widely studied, yet its hypoglycemic activity is not clear. Here, using biochemical and cell viability assays, site-directed mutagenesis, immunoblotting, and immunofluorescence staining, we found that a natural product, antroalbol H isolated from the basidiomycete mushroom Antrodiella albocinnamomea, increases cellular glucose uptake in murine L6 myotubes and 3T3-L1 adipocytes. Of note, our results indicated that this effect is related to LKB1-mediated Thr-172 phosphorylation of AMPKα. Furthermore, we observed that antroalbol H induces the phosphorylation of LKB1 specifically at Thr-189 and changes subcellular localization of LKB1. Finally, antroalbol H treatment strikingly promoted glucose transporter type 4 (GLUT4) translocation to the plasma membrane. We conclude that antroalbol H promotes Thr-189 phosphorylation of LKB1, leading to AMPK activation, revealing this residue as a potential target for increasing glucose uptake, and that antroalbol H therefore has potential for managing hyperglycemia.

Ten previously undescribed triterpenoid congeners, namely irpeksolactins A–J, together with eighteen known ones, were isolated from the fruiting bodies of the rainforest-dwelling medicinal fungus Irpex lacteus. The structures of all the isolates were characterized by extensive spectroscopic approaches, including 1D & 2D NMR and MS spectroscopic methods. Irpeksolactin J displayed selective and weak cytotoxicity against the human lung cancer cell line A549 and the human hepatocellular carcinoma cell line SMMC-7721.

Phytochemical investigation on the fermentation broth of the fungus Stereum hirsutum led to the isolation of ten steroids, including two previously unreported ones, namely steresterones A (1) and B (2). The semi-synthesis products 3a and 3b were prepared by reduction of the known compound 3 with NaBH4. Their structures and absolute configurations were established via 1D & 2D NMR spectroscopic analysis, and TDDFT/ECD calculations as well as single crystal X-ray diffraction analysis. The structure of 3 which harbored a 5β-H was confirmed by single crystal X-ray diffraction analysis for the first time. All the compounds reported in this study were evaluated for their cytotoxicity against five human cancer cell lines. Bioassay results revealed that 3, 4, 6―9 displayed significant anti-proliferative effects with IC50 values varying from 2.3 to 34.3 μM. The structure-activity relationships of 3, 3a, 3b were discussed.

A new cadinane-type sesquiterpenoid, microporotriol (1), together with four known compound, 5-methylresorcinol (2), (22E,24R)-ergosta-4,6,8(14),22-tetraen-3-one (3), (22E,24R)-ergosta-5,7,22-trien-3β-ol (4), (22E,24R)-5α,8α-epidioxy-ergosta-6,22-dien-3β-ol (5), were isolated from the fermentation broth of the wood decaying fungus Microporus affinis HFG829. The structures of the compounds were established by extensive spectroscopic methods, including 1D & 2D NMR, along with HRMS spectroscopic analysis. The relative configuration of 1 was confirmed by NMR calculation. Compound 1 was evaluated for the cytotoxicity against five human cancer cell lines.

Two highly conjugated alkaloids xylaridines A (1) and B (2) were obtained as racemates from the fungus Xylaria longipes. They were resoluted into optically pure enantiomers, respectively. Their structures were determined by extensive spectroscopic analyses, X-ray diffraction, and equivalent circulating density (ECD) calculations. Compound 1 possesses a 5/6/6/5/5 fused ring system with unique 2-azaspiro[4.4]nonane substructure. The hypothesis of biosynthesis pathways for 1 and 2 was proposed.

Two new 24-methyl-lanostane triterpenoids, fomitopsins I (1) and J (2), were isolated together with seven known compounds (3–9), from fruiting bodies of the basidiomycete Fomitopsis species. The structures were elucidated by spectroscopic analysis. Their antibacterial and cytotoxic activities were evaluated. One of the known compounds (6) exhibited antibacterial activity against Gram-positive bacteria, Bacillus cereus (MIC 6.25 μg/ml) and Enterococcus faecium (MIC 12.5 μg/ml).

Four new polyketides, namely bellidisins A-D (1-4), were isolated from rice fermentation extract of endophytic fungus Phoma bellidis, along with three known compounds pinolidoxin (5), 5,6-epoxypinolidoxin (6), and 2-epi-herbarumin II (7). Their structures and absolute configurations were determined by 1D and 2D NMR, HRESIMS and ECD calculation. Their cytotoxicity was evaluated against human cancer cell lines HL-60, A549, SMMC-7721, MCF-7, and SW480. Compound 4 showed significant cytotoxicity on these five cell lines with IC50 value ranged from 3.40 to 15.25 μM, which is stronger than cisplatin (4.86–27.70 μM).

Irpexolidal (1), a triterpenoid with an unprecedented carbon skeleton, along with its biogenetic-related compound irpexolide A (2), were isolated from the fruiting bodies of the medicinal fungus Irpex lacteus. Irpexolidal features a 6/5/6/5/6/5-fused polycyclic skeletal system which arises from the eburicane-type triterpene by a 6,7- seco-6,8- cyclo pattern. The structures of 1 and 2 were established by means of extensive spectroscopic techniques, ECD calculation, and DP4+ probability based on GIAO NMR chemical shift calculations. The plausible biosynthetic pathways for compounds 1 and 2 were proposed. Their biological activities were evaluated.

Two new Tricholoma terpenoids, tricholopardins A and B, were isolated from the fruiting bodies of the basidiomycetes Tricholoma pardinum. Their structures were elucidated by spectroscopic methods, as well as electronic circular dichroism and optical rotatory dispersion calculations. Tricholopardin A potently inhibited nitric oxide production in lipopolysaccharide-induced RAW264.7 macrophages with an IC50 of 0.08 μM. Its anti-inflammatory effects on three inflammatory mediators were also evaluated. A plausible biosynthetic pathway for these products is discussed.