Chemical Consitituents And Bioactivities Of Apple-Shaped Pear Peel, Scabiosa Comosa And Scabiosa Tschillensisi

Part 1 Apple-shaped pear (ASP), the fruit of Pyrus pyrifolia cv. pingguoli (Rosaceae) tree, is one of the most popular fruits in the northern part of China. Two extracts of ASP from Hetao plain, Inner Mongolia, were evaluated for their hepatoprotective effects on acute mouse liver damage induced by carbon tetrachloride (CCl4). The fruit extracts significantly prevented the increase of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, and improved histopathological changes. In addition, Ultra Performance Liquid Chromatography/Mass Spectrometry (UPLC-MS) based quantification revealed that the serum levels of 4 taurine conjugated bile acids were much higher in the extract or positive control (silymarin) treated mice than in the untreated mice, suggesting that the hepatoprotective effects may be partly mediated by the alteration of bile acid secretions and the concentration changes of serum bile acids may serve as biochemical indexes for screening hepatoprotective agents. The extracts of ASP peels exhibited impressive scavenging activity on DPPH· and protective effect on ROO induced DNA damage. An experiment using UPLC-MS coupled with DPPH revealed that luteolin-7-glucoside, 3,5-dicaffeoylqunic acid, and rutin are the bioactive constituents of ASP for radical scavenging. Quantification results indicated that besides polyphenols, ASP contained large amounts of triterpenes, especially, ursolic acid which is a well known hepotaprotective compound. These findings provided evidences for the use of ASP as liver-protective supplements.Part 2 The inflorescences of Scabiosa comosa Fisch. ex Roem. et Schult (SC) and S. tschilliensis Grunning (ST) are used in traditional Mongolian medicine for anti-inflammatory, antipyretic and treatment of liver diseases. The antioxidant and maltase inhibitory activities of the 70% ethanol extracts of SC and ST were investigated. Both extracts showed strong antioxidant activities as measured by DPPH, ABTS and FRAP methods, and demonstrated potent inhibitory activity against maltase. In a phytochemical investigation,3 dicaffeoylquinic acids (DCQAs) and 1 of the ethyl ester were firstly purified or identified from Scabiosa genus. These were 3,4-DCQA,3,5-DCQA,4,5-DCQA and 3,5-DCQA ethyl ester. UPLC-MS based quantification revealed that the most abundant constituents of SC and ST were 3,5-DCQA, chlorogenic acid and some glycosides of luteolin or apigenin. The amounts of these compounds, especially, that of apigenin-7-arabino(1-6)-glucoside were higher in ST than in SC. Eleven antioxidant compounds were identified from the extracts with DPPH-UPLC-MS method. Of these,3,5-DCQA and chlorogenic acid showed excellent radical scavenging ability with IC50 values being 3.6 and 4.7 μg/mL, respectively, as measured by conventional method using pure compounds. In addition,3,5-DCQA and chlorogenic acid demonstrated anti-HCV activity on cell based bioassay.