Baiping Ma

Two new furostanol saponins and one new spirostanol saponin were isolated from the rhizome of Paris polyphylla Smith var. yunnanensis, together with 18 known steroidal saponins. The structures of the new steroidal saponins were elucidated as 26-O-beta-D-glucopyranosyl-(25R)-5-ene-furost-3 beta, 17 alpha, 22 alpha, 26-tetrol-3-O-alpha-L-arabinofuranosyl-(1-->4)-[alpha-L-rhamnopyranosyl-(1-->2)]-beta-D-glucopyranoside (2, parisyunnanoside A), 26-O-beta-D-glucopyranosyl-(25R)-5, 20 (22)-diene-furost-3 beta, 26-diol-3-O-alpha-L-arabinofuranosyl-(1-->4)-[alpha-L-rhamnopyranosyl-(1-->2)]-beta-D-glucopyranoside (7, parisyunnanoside B), and (25R)-spirost-5-ene-3 beta, 12 alpha-diol-3-O-alpha-L-rhamnopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->4)-[alpha-L-rhamnopyranosyl-(1-->2)]-beta-D-glucopyranoside (13, parisyunnanoside C) by MS and 1 D and 2 D NMR analysis. The isolated compounds were evaluated for their cytotoxicity against HL-60 human promyelocytic leukemia cells. Our results showed that the spirostanol framework of the aglycone and the terminal alpha-L-rhamnopyranosyl with 1-->2 linkage to the sugar chain of saponins at C-3 are essential for their high cytotoxicity, whereas the hydroxy group substitution at C-12 or C-17 of the aglycone causes a reduction in their activity.

A simple, accurate and reliable high performance liquid chromatography coupled with photodiode array detection (HPLC-DAD) method was developed and then successfully applied for simultaneous quantitative analysis of eight compounds, including chlorogenic acid (1), (R/S)-flavanomarein (2), butin-7-O-β-d-glucopyranoside (3), isookanin (4), taxifolin (5), 5,7,3′,5′-tetrahydroxyflavanone-7-O-β-d-glucopyranoside (6), marein (7) and okanin (8), in 23 batches of snow chrysanthemum of different seed provenance and from various habitats. The results showed total contents of the eight compounds in the samples with seed provenance from Keliyang (Xinjiang, China), are higher than in samples from the other five provenances by 52.47%, 15.53%, 19.78%, 21.17% and 5.06%, respectively, which demonstrated that provenance has a great influence on the constituents in snow chrysanthemum. Meanwhile, an ultra performance liquid chromatography coupled with electrospray ionization and quadrupole time-of-flight-mass spectrometry (UPLC-ESI-QTOF-MS) was also employed to rapidly separate and identify flavonoids and phenolic acids in snow chrysanthemum from Keliyang. As a result, a total of 30 constituents, including 26 flavonoids and four phenolic acids, were identified or tentatively identified based on the exact mass information, the fragmentation characteristics, and retention times of eight reference standards. This work may provide an efficient approach to comprehensively evaluate the quality of snow chrysanthemum.

Liupao tea, a popular dark tea, exhibited anti-diabetic activity in Chinese tea culture. However, the bioavailability of the main active components is low. Therefore, the relationship between the anti-diabetic activity and the modulation of gut microbiota was investigated in this study for the first time. Liupao tea extract (LTE) could significantly alleviate hyperglycemia, insulin-resistance, and plasma lipid profiles. The hypoglycemic effect of high-dose LTE was comparable to that of metformin. Importantly, LTE exhibited beneficial effect on modulating the diabetic-induced disorder of gut microbiota, such as increasing Bacteroidetes/Firmicutes ratio and up-regulating putative short-chain fatty acid (SCFA)-producing bacteria, including Prevotella and Bacteroides. Moreover, 29 key phylotypes were significantly correlated with at least one diabetic index. In conclusion, LTE could be developed into an anti-diabetic functional beverage and its beneficial effects is likely to be associated with the prebiotic effects for increasing the level of SCFAs and the relative abundance of SCFA-producing bacteria.