Enrichment optimisation and identification of total iridoid glycosides from Thunb. and its anti-inflammatory activity.

The total iridoid glycosides (TIG) from Thunb. were firstly enriched by D316 anion exchange resin, using the response surface method (RSM) model to optimise the enrichment parameters, leading to the optimised RSM parameters of 1.25 g sample weight, 8.

Polysaccharide isolated from Dioscorea septemloba improves hyperuricemia and alleviates renal fibrosis through gut-kidney axis in mice.

Hyperuricemia (HUA) is a common metabolic disorder that often accompanies kidney diseases such as tubule damage and renal interstitial fibrosis. The preventive and therapeutic effects of Dioscorea septemloba, an anti-HUA herb, polysaccharide of which was considered as the main active ingredient on HUA, need to be explored. The major polysaccharide component, BXP, was purified from Dioscorea septemloba, with an average molecular weight of 10.

Purification of triterpenoid saponins and 25R/25S-inokosterone from Achyranthes bidentata Bl. by high-speed countercurrent chromatography coupled silver nitrate coordination.

An effective method by high-speed countercurrent chromatography coordinated with silver nitrate for the preparative separation of sterones and triterpenoid saponins from Achyranthes bidentata Blume was developed. Methyl tert-butyl ether/n-butanol/acetonitrile/water (4:2:3:8, v/v/v/v) was selected for 20-hydroxyecdysone (compound 1), chikusetsusaponin IVa methyl ester (compound 4), 2'-glycan-11-keto-pigmented saponin V (compound 5), as well as a pair of isomers of 25S-inokosterone (compound 2) and 25R-inokosterone (compound 3), which were further purified by silver nitrate coordinated high-speed countercurrent chromatography. What is more, dichloromethane/methanol/isopropanol/water (6:6:1:4, v/v/v/v) was applied for calenduloside E (compound 6), 3β-[(O-β-d-glucuronopyranosyl)-oxy]-oleana-11,13-dien-28-oic acid (compound 7), zingibroside R1 (compound 8) and chikusetsusaponin IVa (compound 9).

Dissociative chemisorption of O on Ag and AgIr (n = 3-26) clusters: a first-principle study.

Understanding the interactions between O2 and small metal clusters is of great importance in exploring heterogeneous catalysis particularly involving an oxidation reaction. We herein present the dissociative chemisorption of O2 on Agn and Agn-1Ir clusters (n = 3-26) by using density functional theory calculations. Combining a particle swarm optimization algorithm and a minima hopping method, we have optimized and obtained stable geometric structures of Agn and Agn-1Ir clusters without and with O2 adsorption.