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Using the wave model WAVEWATCH III (WW3), we simulated the generation and propagation of typhoon waves in the South China Sea and adjacent areas during the passage of typhoon Nesat (2011). In the domain 100°-145°E and 0°-35°N, the model was forced by the cross-calibrated multi-platform (CCMP) wind fields of September 15 to October 5, 2011. We then validated the simulation results against wave radar data observed from an oil platform and altimeter data from the Jason-2 satellite. The simulated waves were characterized by five points along track using the Spectrum Integration Method (SIM) and the Spectrum Partitioning Method (SPM), by which wind sea and swell components of the 1D and 2D wave spectra are separated. There was reasonable agreement between the model results and observations, although the WW3 wave model may underestimate swell wave height. Significant wave heights are large along the typhoon track and are noticeably greater on the right of the track than on the left. Swells from the east are largely unable to enter the South China Sea because of the obstruction due to the Philippine Islands. During the initial stage and later period of the typhoon, swells at the five points were generated by the propagation of waves that were created by typhoons Haitang and Nalgae. Of the two methods, the 2D SPM method is more accurate than the 1D SIM which overestimates the separation frequency under low winds, but the SIM method is more convenient because it does not require wind speed and wave direction. When the typhoon left the area, the wind sea fractions decreased rapidly. Under similar wind conditions, the points located in the South China Sea are affected less than those points situated in the open sea because of the influence of the complex internal topography of the South China Sea. The results reveal the characteristic wind sea and swell features of the South China Sea and adjacent areas in response to typhoon Nesat, and provide a reference for swell forecasting and offshore structural designs. [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]

The interdecadal variation of coral grayness in northern South China Sea (SCS) is studied using the annual mean coral grayness in northern SCS from 1789 to 1992 and annual precipitation at Guangzhou from 1908 to 1992 by Singular Spectrum Analysis (SSA), correlation analysis, Mann-Kendall's abrupt change analysis and composite analysis. The interdecadal variation of south China precipitation as reflected by the series of Guangzhou precipitation rebuilt with the coral grayness is discussed. The results show that the variation of coral grayness in SCS has significant terms of tendency, much-weighted interdecadal variation and weak interannual variation. There was a century-scale abrupt change of coral grayness at the end of the 1880s that changed from positive anomalies to negative anomalies. The global field of SST difference corresponding to the point of abrupt change was negative anomalies over the SCS and neighboring northern Indian Ocean, most of central and western Pacific Ocean and coastal areas of the northern Atlantic Ocean. The large-scale distribution of SST anomalies is concomitant with the century-scale abrupt change of coral grayness in SCS. Negative correlation exists between the coral grayness in SCS and precipitation in Guangzhou on the interdecadal scale and the interdecadal precipitation in Guangzhou as reflected by the interdecadal data of SCS coral grayness shows that the interdecadal variation of south China precipitation changes significantly from phase to phase. The current study aims at contributing in the effort of identifying alternative indexes for climate change in south China on the interdecadal scale and beyond. [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 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]

The article describes the isolation of cerebrosides from the green brittle star Ophiarachna incrassata. The green brittle star was collected in January 2005 in the South China Sea at a depth of 3 meter. It was extracted twice with ethanol. Spectral methods and chemical transformations were used to identify the structures of the cerebrosides.