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The S1 state decay dynamics of 2-hydroxypyridine following UV excitation at a wavelength range of 276.9−250.0 nm is investigated using femtosecond time-resolved photoelectron imaging technique. Based on pump wavelength dependence of the decay dynamics, a refined decay picture is proposed. At pump wavelength of 276.9 nm, the S1 state is depopulated through intersystem crossing to lower triplet state(s). At 264.0 nm, both intersystem crossing to lower triplet state(s) and internal conversion to the ground state are in operation. At 250.0 nm, internal conversion to the ground state becomes dominated. [ABSTRACT FROM AUTHOR]

N -ethylpyrrole is one of ethyl-substituted derivatives of pyrrole and its excited-state decay dynamics has never been explored. In this work, we investigate ultrafast decay dynamics of N - ethylpyrrole excited to the S1 electronic state using a femtosecond time-resolved photoelectron imaging method. Two pump wavelengths of 241.9 and 237.7 nm are employed. At 241.9 nm, three time constants, 5.0±0.7 ps, 66.4±15.6 ps and 1.3±0.1 ns, are derived. For 237.7 nm, two time constants of 2.1±0.1 ps and 13.1±1.2 ps are derived. We assign all these time constants to be associated with different vibrational states in the S1 state. The possible decay mechanisms of different S1 vibrational states are briefly discussed. [ABSTRACT FROM AUTHOR]

Objective: To get active secondary metabolites from the fungus Paecilomyces sp.., Methods: The strain Paecilomyces sp. was further grown in solid-substrate fermentation cultures, the metabolites were got by application of different separation techniques, such as silica gel, Sephadex LH-20 column chromatography, and reversed-phase high performance liquid chromatography. Their structures were identified by comprehensive spectroscopic methods., Results: Four compounds were isolated and identified as Cerebroside C (1), Cerebroside D (2), 2-Hydroxybenzyl alcohol (3), 2-(4-Hydroxyphenyl) ethanol., Conclusion: Four compounds are isolated from Paecilomyces sp. for the first time.

Objective: The metabolites of HS-3 associated with holothurians were studied, which was identified by molecular biology as Alternaria sp.., Methods: The holothurians were gathered from the Sea of Zhifu Islet, Shandong Province. HS-3 Alternaria sp. was culternitived in potato medium, and four compound was got by TLC, chromatography and HPLC, and 1-hydroxyl-3-methylanthracene-9,10-dione (1), chrysophanol (2), sterigmatocystin (3) and cerebroside (4) were elucated by modern spectrum., Conclusion: All of this provides scientific data for further study of holothurians, and the four coumpouns are isolated from the microbe associated with holothurians for the first time.

Objective: To get active metabolites from the microbes associated with sea cucumber., Methods: Fungus was isolated from the sea cucumber, and the species was identified by molecular biology, and then was cultivated in GYP medium, and the metabolites were got by chromatography. Their structures were identified by comprehensive spectroscopic methods., Results: Fungus HS-1 Epicocum sp. was isolated from the sea cucumber in Weihai, Yellow Sea. Four compounds were got as 5-methyl-6-hydroxy-8-methyoxy-3-methylisochroman (1), 8-hydroxy-3-methylisochroman-1-one (2), peroxy-ergosterol (3) and succinic acid (4)., Conclusion: Fungus HS-1 Epicocum spp. is first isolated from the sea cucumber sample, this research provides new idea for further development of sea cucumber.

Objective: The secondary metabolites of the fungus ZZF13 isolated from the leaves of the mangrove sample Kandelia candel in Zhanjiang and Guignardia sp. 4382 isolated from bark of Kandelia candel (endophyte) of Mai Po, Hong Kong were studied., Methods: The compounds were isolated by siliga gel, and their structures were identified by IR, MS and NMR., Results: Four compounds were isolated from the culture of this strain. Their structures were identified as Bacillpsporin C (1), 5-carboxymellein (2), 5-methylmellein (3) and 1-(2,6-dihydroxyphenyl) butanone (4)., Conclusion: The compounds 2 - 4 are isolated from the Guignardia sp. of Marine fungi for the first time.

To obtain water-soluble holothurian glycosides with high tumor suppressing activities from Apostichopus japonicus, macroporous resin, silica gel and gel-filtration column chromatograghy were used to purify the water-soluble holothurian glycosides, and their tumor suppressing activity and inducing apoptosis of tumor cells were examined in this study. The 70% ethanol fraction of macroporous resin column, the pSC-2 and pSC-3 fractions from silica gel column showed very strong tumor suppressing activity towards HeLa cells, A-549 lung cancer cells, SGC-7901 stomach cancer cells and Bel-7402 liver cancer cells. SC-2 and SC-3 fraction purified from Sephadex LH-20 gel-filtration column chromatography, with a purity above 99.6%, all had the properties of triterpenoid glycosides. Purified SC-2 fraction had remarkable tumor suppressing activity on HeLa cells in a dose- and time-dependent manner, and had prominent tumor suppressing activity to mouse S180 solid tumors in a dose-dependent manner. Besides, the SC-2 fraction also had remarkable ability in elevating mouse thymus index and spleen index. The purified SC-2 fraction could induce apoptosis of HeLa cells in a dose-dependent manner, and DNA fragmentation of HeLa cells occurred after treated 12 h with 10 mg x L(-1) and 50 mg x L(-1) of SC-2 fractions. From the results, it can be concluded that the purified SC-2 fraction of water-soluble holothurian glycosides has extremely strong tumor suppressing activity, and the suppression is realized by inducing tumor cells to undergo apoptosis. This study lays solid foundation for development of highly effective new natural anticancer agents from sea cucumbers.

Objective: To optimize the preparation of Shandantong sustained-release tablets., Methods: We used the orthogonal experiment to optimize the preparation and determined the contents of Shanzha total flavonoids and tanshinone. Involved technology and hydrophilicity skeleton materials were adopted to prepare the sustained-release tablets., Results: The best extracted progress of Shanzha total flavonoids and tanshinone were A2B2C1 and A3B1C2, respectively. The hydrophilicity skeleton materials were gel HPMC and acrylic resin., Conclusions: The concentration of alcohol and percolated speed are significant factors on the extracted efficacy by analysis of variance. The preparation and prescription of this sustained-release tablet is reasonable.

Objective: To explore the origin of Monascus Rice., Methods: The relative literature were investigated and classified., Results: It was verifiable that the record of Monascus Rice in Chu Xue Ji ([Chinese characters: see text]), a subject-based reference book compiled by Xu Jian in the Tang Dynasty, was excerpted from the metrical verse Qi Shi ([Chinese characters: see text]) written by Wang Can in the Dong Han Dynasty. It is no doubt the name of Monascus Rice was originally used in this peried., Conclusion: The use of Monascus Rice can be traced at least to the Han Dynasty.