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A new steroid glucoside (1), along with nine known steroids (2-10) and four known sorbicillinoids (11-14), were isolated from the endophytic fungus Trichoderma sp. Xy24. Their structures were elucidated on the basis of spectroscopic data analyses and by comparison with reported data. Compounds 3, 5-7, 9, 10, and 13 exhibited significant inhibitory effects on HIV-1 virus with IC 50 values ranging 1.9-9.3 μM; compounds 10, 13, and 14 showed potent inhibitory activity on LPS-induced NO production in BV2 microglia cells with inhibitory rates of 108.2, 100, and 75.1% at 10 μM, respectively. In addition, compound 10 displayed moderate cytotoxicity against BCG823 and HePG2 cell lines with IC 50 values of 11.1 and 17.7 μM, respectively.

The glycosides of 4'-demethylepipodophyllotoxin (DMEP) possess various pharmacological activities; however, the chemical synthesis of these glycosides faces challenges in regioselectivity, stereoselectivity, and the protection and de-protection of functional groups. In this work, a novel glycosyltransferase (GT) gene AbGT5 from Aloe barbadensis was successfully cloned, heterogeneously expressed and purified. Recombinant AbGT5 was able to catalyze the glycosylation of DMEP and the glycosylated product, which was separated from the preparative scale reaction, was characterized as DMEP 4'-O-β-D-glucoside via MS, 1H-NMR, 13C-NMR, HSQC and HMBC. According to the investigations of enzyme properties, AbGT5 show the highest activity around 20 ℃ in the buffer of pH 9.0, and it was independent of divalent metal ions. Under the optimum conditions, the conversion rate of DMEP can reach 80%. Above all, in this work the enzymatic glycosylation of DMEP was achieved with high efficiency by the novel GT AbGT5., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Syringin, chlorogenic acid and 1,5-dicaffeoylquinic acid are three main bioactive ingredients in herbs of Saussurea involucrata with various pharmacological properties, while their contents are very low. In this study, the biosynthesis of syringin, chlorogenic acid and 1,5-dicaffeoylquinic acid in the cell suspension cultures of S. involucrata were regulated by feeding carbon sources and precursors, which resulted in a great increase of the contents and yields of the above three bioactive ingredients. After 16 days of fermentation, the yields of syringin, chlorogenic acid and 1,5-dicaffeoylquinic acid reached 339.0, 225.3, 512.7 mg x L(-1), respectively. Meanwhile, their contents increased up to 67.9, 1.9, 10.6 times of wild medicinal material, respectively. The results provided a solid basis for further studies on application of cell suspension cultures of S. involucrata for large-scale production of bioactive compounds syringin, chlorogenic acid and 1,5-dicaffeoylquinic acid.

Syringin is one of the main bioactive ingredients in Saussurea involucrata. In this study, various chromatographic techniques were employed to isolate and purify syringin in the polar extraction of cell suspension cultures of S. involucrata. The structure of syringin was characterized by the analysis of spectroscopic data. A quantitative analytical method for the content of syringin in cultures of S. involucrata was established with RP-HPLC. The method is convenient, accurate and reliable. All this results provided a basis for further studies on application of cell suspension cultures of S. involucrata for large-scale production of bioactive compound syringin.