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Marine fungi can metabolize structurally diverse active components, and have become an important source of drug lead molecules. In the present study, the chemical investigation on the EtOAc extract of the fermentation broth of the marine-derived fungus

Five new polyketides named alternafurones A (1) and B (2), alternapyrones M-O (3–5), together with fourteen known ones (6–19), were isolated from the desert-plant-derived fungus Alternaria sp. HM 134. The structures of the new compounds were elucidated from spectroscopic data and ECD spectroscopic analyses. Alternafurones A and B represent polyketides with an unprecedented 6/5/6 skeleton core. Compounds 1, 2 and 4 showed definite inhibitory activities against isocitrate dehydrogenase 1 gene (IDH1 R132h) with IC50 values of 29.38, 19.41 and 14.14 μg/ml, respectively. Seven compounds (6, 7, 9–12, 14) showed potent protein tyrosine phosphatase 1B (PTP1B) inhibitory activity with IC50 values ranging from 0.97 μg/ml to 89.80 μg/ml.

Macrofungus

Five new polyketides named alternafurones A (

Primary liver cancer is the third most common malignancy, and hepatocellular carcinoma is its main subtype, with a high recurrence rate and high mortality. Intestinal microflora and metabolic disorders are present in most HCC patients. Traditional Chinese medicine (TCM) plays an important role in the composition of intestinal microorganisms and the transformation of active metabolites. Many scholars are trying to develop related drugs to assist in the treatment of liver cancer. In the preliminary study of the research group, it was found that the Jiawei Xiaoyao San has a certain therapeutic effect on liver cancer, but the specific mechanism is still unclear. Therefore, this study constructed a liver cancer rat model with liver stagnation and spleen deficiency, to explore the regulatory effect of Jiawei Xiaoyao San on plasma metabolites and intestinal microflora and to find the potential mechanism of Jiawei Xiaoyao San in the treatment of liver cancer. Plasma samples and fecal samples were collected from liver cancer rats with liver depression and spleen deficiency for microbiome 16S rDNA sequencing and metabolic ESI-QTRAP-MS/MS analysis. Various bioinformatics methods were used to analyze the dataset individually and in combination. The analysis and identification of plasma metabolomics showed that the intervention effect of Jiawei Xiaoyao San on liver cancer rats with liver depression and spleen deficiency was related to 11 differential metabolites and signal pathways such as primary bile acid biosynthesis, phenylalanine metabolism, pantothenate and COA biosynthesis, metabolic pathways, cholesterol metabolism, and bile secretion. Combined with fecal microbiological analysis, it was found that Jiawei Xiaoyao San could significantly change the composition of intestinal flora in liver cancer rates, increase beneficial bacteria, and reduce the composition of harmful bacteria. This study provides some experimental basis for the traditional Chinese medicine theory and clinical application of Jiawei Xiaoyao San in the adjuvant treatment of liver cancer. The potential mechanism may be to regulate metabolism and intestinal flora to play the role of regulating liver depression, activating blood, and detoxifying, to achieve the purpose of adjuvant treatment of liver cancer.

Marine fungi can metabolize structurally diverse active components, and have become an important source of drug lead molecules. In the present study, the chemical investigation on the EtOAc extract of the fermentation broth of the marine-derived fungus Trametes sp. ZYX-Z-16 led to the isolation of eight meroterpenoids (1–8), including two undescribed ones, together with ten ergostane steroid analogues (9–18). The structures of two new spiromeroterpenoids, asnovolin H (1) and asnovolin I (2), were determined based on 1D, 2D NMR, and HRESIMS spectroscopic data along with ECD spectra calculations. All compounds were tested for antibacterial and α-glucosidase inhibitory activity. Among them, compound 12 showed definite antibacterial activities against Staphylococcus aureus ATCC 6538 (MIC 32 μg/mL) and Bacillus subtilis ATCC 6633 (MIC 16 μg/mL). In addition, compounds 9 and 10 showed superior inhibitory activity, with IC50 values of 104.1 and 111.3 μM, respectively, to the positive control acarbose (304.6 μM).

Macrofungus Ganoderma luteomarginatum is one of the main species of Ganoderma fungi distributed in Hainan province of China, the fruiting bodies of which have been widely used in folk as a healthy food to prevent tumors. To explore the potential cytotoxic constituents from G. luteomarginatum, the phytochemical investigation on the ethyl acetate soluble fraction of 95% ethanolic extract from the fruiting bodies of this fungus led to the isolation of twenty-six lanostane triterpenoids (1–26), including three undescribed ones (1–3), together with eight ergostane steroids (27–34). The structures of three new lanostane triterpenoids were elucidated as lanosta-7,9(11)-dien-3β-acetyloxy-24,25-diol (1), lanosta-7,9(11)-dien-3-oxo-24,26-diol-25-methoxy (2), and lanosta-8,20(22)-dien-3,11,23-trioxo-7β,15β-diol-26-oic acid methyl ester (3) by the analysis of 1D, 2D NMR, and HRESIMS spectroscopic data. All isolates were assayed for their cytotoxic activities using three human cancer cell lines (K562, BEL-7402, and SGC-7901) and seven lanostane triterpenoids (1, 2, 7, 13, 18, 22, and 24), and one ergostane steroid (34) showed definite cytotoxicity with IC50 values that ranged from 6.64 to 47.63 μg/mL. Among these cytotoxic lanostane triterpenoids, compounds 2 and 13 showed general cytotoxicity against three human cancer cell lines, while compounds 1 and 18 exhibited significant selective cytotoxicity against K562 cells with IC50 values of 8.59 and 8.82 μg/mL, respectively. Furthermore, the preliminary structure–cytotoxicity relationships was proposed.

Five new perylenequinone derivatives, altertoxins VIII–XII (1–5), as well as one known compound cladosporol I (6), were isolated from the fermentation broth of the marine-derived fungus Cladosporium sp. KFD33 from a blood cockle from Haikou Bay, China. Their structures were determined based on spectroscopic methods and ECD spectra analysis along with quantum ECD calculations. Compounds 1–6 exhibited quorum sensing inhibitory activities against Chromobacterium violaceum CV026 with MIC values of 30, 30, 20, 30, 20 and 30 μg/well, respectively.

In this paper, a method to design robust sliding hyperplane is proposed in the presence of mismatched parametric uncertainty for the linear control system with time-delays based on quadratic stability. The robust sliding hyperplane is constructed from a Riccati inequality associated with quadratic stabilizability. The proposed method enables us to deal with structured uncertainly and optimize the sliding motion by applying the guaranteed cost control idea.