Isolation,Identification And Antioxidant Activities Of Anthraquinones And Fatty Acids From Cortinarius Purpurascens

Cortinarius purpurascens Fr.(Zi Mo in Chinese)which is mainly produced in the Ho-Lan Mountains of Inner Mongolia Alxa League and Ningxia,is a kind of rare and edible fungus.In this research,we investigated the anthraquinones and fatty acids of the fruit body of C.purpurascens,and obtained the following result.1.The fungus was extracted with methanol,and the extract was partitioned with ethylacetate and other solvents.Separated and purification were carried out through various column chromatography methods to afford five compounds.Then through analysis of their spectra(1H-NMR,13C-NMR,HMBC,HSQC,H-H COSY,UHPLC-MS)data,and comparison with reference data,the chemical structures were identified as physcione(1),(P)-anhydroflavomannin-9,10-quinone 6,6',8'-tri-O-methyl ether(2),(M)-anhydroflavomannin-9,10-quinone 6,6',8 '-tri-O-methyl ether(3),rufoolivacin(4),palmitic acid(5).Five other fatty acids were identified by comparison with standard compounds in UHPLC-MS as,stearic acid(6),a-linolenic acid(7),linoleic acid(8),oleic acid(9),and palmitoleic acid(10).2.Bioactivity assessment revealed that among different extracts,the methanol extract and the ethylacetate soluble part were the most active in scavenging DPPH and.OH radicals with radical scavenging rates of 88.3%and 96.8%,respectively at 0.5 mg/mL.The four quinone compounds showed stronger radical scavenging activity than the ethylacetate soluble part.Among these chemical constituents,(P)-anhydroflavomannin-9,10-quinone 6,6 ',8 '-tri-O-methyl ether showed the strongest.OH radical scavenging activity,while physcione showed the strongest activity against DPPH.3.The contents of these 10 chemical constituents in different extracts of the fungus were analyzed with LC-MS,and the results showed that the ethylacetate soluble part contained the largest amounts of phenolic compounds with physcion being in the highest level.On the other hand,the petroleum ether soluble part was rich in fatty acids.