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A new lactone, 1,8dihydroxy10methoxy3methyldibenzob,eoxepine6,11dione 1, and two new xanthones, 1hydroxy8hydroxymethyl6methoxy3methyl9Hxanthen9one 2 and 1hydroxy8hydroxymethyl3methoxy6methyl9Hxanthen9one 3, were isolated from a mangrove endophytic fungus Phomasp. SK3RW1M collected from the South China Sea. This is the first report on xanthone derivatives isolated as secondary metabolites from Phomaspecies. Their structures were elucidated by spectroscopic methods, mainly 1D and 2DNMR techniques, and the structure of compound 2was confirmed by Xray crystallography. Cytotoxicity assays showed that compounds 1–3were inactive against KB and KBv200 cells. [ABSTRACT FROM AUTHOR]

A new naphtho- γ-pyrone, 5-hydroxy-6,8-dimethoxy-2-benzyl-4H-naphtho[2,3-b]-pyran-4-one ( 1), together with three known compounds 5,7-dihydroxy-2-methylbenzopyran-4-one ( 2), 3,5-dihydroxy-2,7dimethylbenzopyran-4-one ( 3) and cyclo(Tyr-Tyr) ( 4) were isolated from the mangrove endophytic fungus Phomopsis sp. ZSU-H26 obtained from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR spectroscopic techniques. Primary bioassays showed that 1 exhibited cytotoxicity against HEp-2 and HepG2 cells with IC50 values of 10 and 8 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

A new polyketide, 2-(7′-hydroxyoxooctyl)-3-hydroxy-5-methoxybenzeneacetic acid ethyl ester ( 1), together with three known compounds dothiorelone A ( 2), B ( 3), and C ( 4) were isolated from the mangrove endophytic fungus Phomopsis sp. ZSU-H76 obtained from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR spectroscopic techniques. Primary bioassays showed that 1 exhibited cytotoxicity against HEp-2 and HepG2 cells with IC50 values of 25 and 30 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

A new alternariol derivative, 2240B ( 1), together with alternariol ( 2), alternariol 4,10-dimethyl ether ( 3), and alternariol 4-methyl ether ( 4), was isolated from the ethyl acetate extract of the liquid medium GYT of No. 2240, the mangrove endophytic fungus from the South China Sea Coast. The structure of compound 1 was unambiguously elucidated as alternariol 4-methyl-10-acethyl ester by spectra including one/two-dimensional NMR, HREIMS, IR, and UV. The structures of compounds 2–4 were also established by spectroscopic analyses and comparison with related literature data. The anticancer tests showed that compounds 2 and 4 had strong activities against KB and KBv200 cells with IC50 values of 3.17, 3.12, and 4.82, 4.94 µg/mL, while compounds 1 and 3 exhibited weak activities against the two kinds of tumor lines with IC50 values of more than 50 µg/mL. [ABSTRACT FROM AUTHOR]

A new isocoumarin, 3,4-dihydro-6-methoxy-8-hydroxy-3,4,5-trimethylisocoumarin-7-carboxylic acid methyl ester ( 1), together with three known compounds, 3,4-dihydro-4,8-dihydroxy-3,5-dimethylisocoumarin ( 2), 3,4-dihydro-8-hydroxy-3-methylisocoumarin-5-carboxylic acid ( 3), and Entinclole SB (4) were isolated from the mangrove endophytic fungus (No. dz17). The structure of the compound 1 was elucidated by analysis of spectroscopic data. Primary bioassays showed that 1 exhibited weak cytotoxicity against Hep-2 and HepG2 cells. [ABSTRACT FROM AUTHOR]

A new isoprenyl phenyl ether, 3-hydroxy-4-(3-methylbut-2-enyloxy)benzoic acid methyl ester ( 1), together with 4-hydroxybenzoic acid ( 2), 2-hydroxy-6-methylbenzoic acid ( 3), and 4-hydroxy-3-methoxybenzoic acid ( 4) were isolated from Mangrove fungus (No. B60) from the South China Sea. The structures of the compounds were established on the basis of NMR spectroscopic and mass spectrometric data. In the preliminary bioassay, compound 1 exhibited antibacterial and antifungal activities. Compound 1 also inhibited cytotoxicity to the hepG2 cell line with an IC50 value of 10.0 µg/mL. [ABSTRACT FROM AUTHOR]

(−)-Byssochlamic acid ( 1) was isolated from mangrove fungus (strain No. k38) from the South China Sea coast. This is the first time that 1 was found in nature. Its structure was confirmed by spectra data and X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

A new isochroman, 6-hydroxy-3-methylisochroman-5-carboxylic acid, and six known compounds were isolated from the culture of marine-derived mangrove fungus 1893#. Their structures were elucidated by analysis of spectroscopic data. [ABSTRACT FROM AUTHOR]

Abstract Two hundred and forty-two actinomycete strains were isolated from the interior of leaves and roots of healthy and wilting banana plants. Most of them were streptomycetes, Streptomyces griseorubiginosus-like strains were the most frequently isolated strains. Community analysis demonstrated increased actinomycete diversity in wilting leaves compared to that in healthy leaves, similar actinomycete communities were found in wilting and healthy roots. Screening of the isolates for antagonistic activity against Fusarium oxysporumf. sp. cubenserevealed that the proportion of antagonistic streptomycetes in healthy roots was higher than that in wilting roots (P < 0.01), but no difference was found between antagonistic strains isolated from healthy and wilting leaves. The potential biological control of Panama disease of banana by endophytic streptomycetes, especially Streptomyces griseorubiginosus-like strains was discussed. [ABSTRACT FROM AUTHOR]

A new xanthone derivative, 8-hydroxy-3-methyl-9-oxo-9 H-xanthene-1-carboxylic acid methyl ether ( 1), was isolated from the co-culture broth of two mangrove fungi (strain No. K38 and E33) isolated from the South China Sea coast. The structure of 1 was determined by comprehensive spectroscopic methods, especially 2D NMR techniques. Primary bioassays showed that compound 1 has inhibitory activity against five microorganisms, including Gloeasporium musae and Peronophthora cichoralearum etc. [ABSTRACT FROM AUTHOR]

A new dihydroisocoumarin derivative containing an isoprenyl group, 5-(3'-methylbut-2'-enyloxy)-3,4-dihydro8-hydroxy-3-methylisochromen-1-one ( 1), was isolated from the mangrove fungus Cephalosporium sp. from the South China Sea. The structure of compound 1 was established by comprehensive analysis of the spectral data, especially 2D NMR spectra. [ABSTRACT FROM AUTHOR]

Two new benzaldehyde derivatives, 6-ethyl-2-hydroxy-4-methoxy-3-methylbenzaldehyde ( 1), 6-ethyl-2,4-dihydroxy-3-methylbenzaldehyde ( 2), together with 2, 4-dihydroxy-3,6-dimethylbenzaldehyde ( 3) were isolated from mangrove fungus (No. ZZF 32#) from the South China Sea. The structures of compounds 1 and 2 were established by comprehensive analysis of the spectral data, especially 2D NMR spectral results. [ABSTRACT FROM AUTHOR]

A new biphenyl derivative 3,5′-dihydroxy-4′,5-dimethoxy-2′-methyl-[1,1′-biphenyl]-2-carboxylic acid methyl ester ( 1), was isolated from the culture broth of a fungus isolated from the rhizosphere soil of mangrove root on the South China Sea. The structure of 1 was determined by comprehensive spectroscopic methods, primarily 2D NMR techniques. [ABSTRACT FROM AUTHOR]

A new metabolite xyloketal H ( 1), was isolated from mangrove fungus Xylaria sp. (No.2508) obtained from the South China Sea. By spectroscopic analyses, primarily 2D NMR methods and X-ray diffraction experiments, its structure was elucidated. [ABSTRACT FROM AUTHOR]

A novel metabolite 1, named xyloketal G, was isolated from cultures of marine derived mangrove fungus Xylaria sp. 2508. Its structure was elucidated by analysis of spectroscopic data. [ABSTRACT FROM AUTHOR]

Three new metabolites (compounds 1-2 and 6), one azaphilone, and two meroterpenes, together with eleven known compounds have been isolated from a mangrove endophytic fungus, Penicillium 303#. Structure elucidation was achieved by 1D and 2D NMR spectroscopy. The absolute configurations of 1and 2 were determined by electronic circular dichroism (ECD). Cytotoxic activities of new compounds 1-2and 6 and compound 7were evaluated in vitro against human cancer lines MDA-MB-435, HepG2, HCT-116, and A549. Those compounds showed weak to moderate cytotoxic activities. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of metabolites of mangrove fungus Xylaria sp. from South China Sea Coast, xyloketal A-D, on the activity of acetylcholinesterase (AChE) in vitro., Methods: Activity of AChE was determined by a modified method of Ellmen. The selectivity of the compounds for AChE and butyrylcholinesterase (BuChE) was also tested and compared with that of a positive control, velnacrine. The inhibitory properties of xylokets on AChE were characterized as well., Results: AChE activity was inhibited by xyloketal A-D in a dose-dependent manner, their IC50 were determined to be 29.9, 137.4, 109.3 and 425.6 micromol/L, respectively. At the same time, velnacrine and all the four compounds showed inhibitory effects on BuChE in different degree, and the inhibitory activity of xyloketals on AChE was found to be reversible and noncompetitive., Conclusion: Xyloketal A-D can inhibit AChE as well as BuChE activity in vitro. So xyloketal A-D were likely considered as drug candidates against Alzheimer' s disease (AD) for further development.