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A new alkaloid named aspergilalkaloid A (1) with pyridoindole hydroxymethyl piperazine dione structure along with six known compounds 2-7 were isolated from deep-sea derived fungus Aspergillus sp. HDN20-1401. The structure including absolute configuration was elucidated by extensive NMR analyses, HRESIMS, ECD calculation, and theoretical NMR calculation with DP4+ analysis. All isolated compounds were tested for antimicrobial and anticancer activity. Aspergilalkaloid A (1) showed inhibitive activity against Bacillus cereus with MIC value of 12.5 μM and weak activity against MRCNS. [ABSTRACT FROM AUTHOR]

Camellia sinensis is being used for decades for its therapeutic efficacies against physiological problems and microbial infections. This study was undertaken to investigate the antibacterial and antifungal potential of aqueous extract of Camellia sinensis. Antibacterial activity was determined by disc and well diffusion assay. MIC and MBC were calculated by broth dilution method. Miles and Misra technique was used to find out colony forming unit per/ml. All the test organisms revealed a diverse range of vulnerability against aqueous extract. Among Gram positive, MRSA showed to be the most sensitive with least MIC and MBC while among Gram-negative Pseudomonas aeruginosa exhibited the highest sensitivity. In Miles and Misra, a progressive decline in log of CFU/ml was observed. In time-kill assay, a decline was noted in the viable count of S.aureus after exposure to 18% aqueous extract of Camellia sinensis. In the present study aqueous extract of Camellia sinensis found to be effective against Gram positive, Gram negative and fungi. The most important finding of this study is its aqueous extract inhibitory effect against drug-resistant microorganisms e.g. MRSA and P. aeruginosa and Candida albicans. [ABSTRACT FROM AUTHOR]

Pseurotin A was isolated from a culture of marine Bacillus sp. FS8D and showed to be active against the proliferation of four different glioma cells with IC50 values of 0.51-29.3 μM. It has been found that pseurotin A downregulated the expression of tumour glycolytic enzymes pyruvate kinase M2 (PKM2) and lactate dehydrogenase 5 (LDH5) and upregulated the expression of pyruvate dehydrogenase beta (PDHB), adenosine triphosphate synthase beta (ATPB) and cytochrome C (Cyto-C), the important regulators for tricarboxylic acid cycle and oxidative phosphorylation. The data suggested that targeting multiple metabolic enzymes might be one of the antiglioma mechanisms of pseurotin A. [ABSTRACT FROM AUTHOR]

Six phenazines including three new ones were isolated from the culture of a marine actinomyceteStreptomycessp. 182SMLY. Based on the analyses of NMR, HRESIMS, optical rotation value, and CD data, the structures of these isolated compounds were determined as new phenazines of (-)-streptophenazines M–O and known phenazines of 1-carbomethoxyphenazine and (-)-streptophenazines A and B. (-)-Streptophenazine B showed activity in suppressing the growth of methicillin-resistantStaphylococcus aureuswith MIC value of 4.2 μg/mL. [ABSTRACT FROM PUBLISHER]

Five curvularin macrolides (1–5) were isolated from the cultured broth of marine actinomycete Pseudonocardia sp. HS7 that was obtained from the cloacal aperture of sea cucumber Holothuria moebii. The structures of these isolates were characterized as (11S,15R)-11-hydroxycurvularin (1), (11R,15R)-11-hydroxycurvularin (2), curvularin-7-O-α-D-glucopyranoside (3), trans-dehydrocurvularin (4) and curvularin (5) based on their NMR and HRESIMS data as well as chemical degradation. Compound 3 is a new macrolide with a rare α-D-glucopyranose substituent. Compounds 1–4, 5a and 5c (the acyl products of 5), suppressed the proliferation of all six tested cancer cell lines and 4 is the most active compound with IC50 values ranging from 0.59 to 3.39 μM. The 11-hydroxycurvularins 1 and 2 also showed antibacterial activity inhibiting the growth of Escherichia coli. [ABSTRACT FROM AUTHOR]

Vorinostat elicitation of the deep-sea fungus Talaromyces sp. HDN17-428 resulted in the isolation of one new compound, talaroenamine L ( 1 ) with unusual leptosphaeronyl moiety and three known compounds ( 2 - 4 ). Structures of 1 - 4 were confirmed by extensive NMR, HRESIMS and OR calculations. Antimicrobial activities of all compounds were tested in which compounds 1 - 4 showed substantial antifungal activities with MIC values ranged from 3.1 to 12.5  μ M.

Pseurotin A was isolated from a culture of marine Bacillus sp. FS8D and showed to be active against the proliferation of four different glioma cells with IC 50 values of 0.51-29.3 μM. It has been found that pseurotin A downregulated the expression of tumour glycolytic enzymes pyruvate kinase M2 (PKM2) and lactate dehydrogenase 5 (LDH5) and upregulated the expression of pyruvate dehydrogenase beta (PDHB), adenosine triphosphate synthase beta (ATPB) and cytochrome C (Cyto-C), the important regulators for tricarboxylic acid cycle and oxidative phosphorylation. The data suggested that targeting multiple metabolic enzymes might be one of the antiglioma mechanisms of pseurotin A.