Yang Chongren

Phyllaemblicin B inhibits Coxsackie virus B3 induced apoptosis and myocarditis.

Coxsackie virus B3 (CVB3) is believed to be a major contributor to viral myocarditis since virus-associated apoptosis plays a role in the pathogenesis of experimental myocarditis. In this study, we investigated the in vitro and in vivo antiviral activities of Phyllaemblicin B, the main ellagitannin compound isolated from Phyllanthus emblica, a Chinese herb medicine, against CVB3. Herein we report that Phyllaemblicin B inhibited CVB3-mediated cytopathic effects on HeLa cells with an IC(50) value of 7.75+/-0.15microg/mL. In an in vivo assay, treatment with 12mgkg(-1)d(-1) Phyllaemblicin B reduced cardiac CVB3 titers, decreased the activities of LDH and CK in murine serum, and alleviated pathological damages of cardiac muscle in myocarditic mice. Moreover, Phyllaemblicin B clearly inhibited CVB3-associated apoptosis effects both in vitro and in vivo. These results show that Phyllaemblicin B exerts significant antiviral activities against CVB3. Therefore, Phyllaemblicin B may represent a potential therapeutic agent for viral myocarditis.

Secoiridoid glucosides from Fraxinus malacophylla

Abstract Two new secoiridoid glucosides, butyl isoligustrosidate and fraximalacoside, were isolated from the leaves of Fraxinus malacophylla, together with the known constituents, isoligustroside, fraxiformoside, isoligustrosidic acid, 1′″-O-β- d -glucosylfraxiformoside, verbascoside, cosmosiin, sitosterol-β- d -glucoside and tyrosol. Their structures have been elucidated by chemical and spectroscopic methods.

Albocycline-type Macrolides with Antibacterial Activities from Streptomyces sp. 4205

The actinomycete genus Streptomyces is characterized by producing bioactive secondary metabolites, including antibiotics. In this study, chemical and biological investigations were carried out on Streptomyces strain 4205 isolated from the paddy soil, leading to the identification and characterization of 10 albocycline‐type macrolides, among which 4 compounds were new, namely albocyclines A–D (1–4). The structures of 1–10 were identified according to the 1D‐ and 2D‐NMR spectroscopic data. Furthermore, compounds 1–10 were evaluated for antimicrobial activity. Compounds 5–7 displayed antimicrobial activities against Candidaalbicans ATCC 90028 with the same MIC value of 10.0 mg/mL and the IC50 values of 1.5, 1.0, and 1.0 mg/mL, respectively. Thus, the research on Streptomyces sp. is of vital significance for developing new antibiotic agents.

Chemical analysis of old tea trees in Bai-Ying-Shan mountain and the origin of cultivated tea.

The contents of dalichasu (1,2-di-O-galloyl-4,6-O-(S)-hexahydroxydiphenoyl-β-D-glucopyranose),catechins,theogallin,gallic acid,caffeine and theanine in old tea trees from Bai-Ying-Shan mountain were quantitatively analyzed by HPLC method,while their total polysaccharides and polyphenols were measured by an UV-Vis spectrophotometer. Based on the chemical composition and morphological variation,the germplasm resource diversity of tea trees in Bai-Ying-Shan Mountain and their relationship with wild Camellia taliensis and cultivated tea (C.sinensis var. assamica) were discussed. The results provided not only the scientific data of quality evaluation of the old tea trees in Bai-Ying-Shan Mountain,but also the chemical evidence for the origin of cultivated tea and the hypothesis that C.taliensis might be one of the origins of cultivated tea during the long natural variation and artificial breeding.