Study On The Composition And Biological Activity Of Phenolic Substances In C. Serrata

This study took Prinsepia utilis Royle Fruits as the experimental material and the composition of phenols of Prinsepia utilis Royle Fruits the research object,total phenolic fraction,flavonoid fraction,anthocyanin fraction?TPF,FF,AF?and the content changes of total phenols,total flavonoids,total anthocyanins and the composition of phenols were studied qualitatively and quantitatively after purification and enrichment;to investigate the changes of antioxidant activities of different components?scavenging DPPH,ABTS free radicals and scavenging reactive oxygen species?ROS??;to investigate the inhibitory activities of different components on digestive enzymes?pancreatic lipase and?-glucosidase?,and the possible inhibitory mechanism of major phenolic substances was studied by molecular docking;to explore the changes in the composition of phenolic substances,antioxidant activity and digestive enzyme inhibitory activity in vitro simulated gastrointestinal digestion.The main research results are as follows:?1?The extraction of P.utilis fruits was successfully separated and enriched into different components by Amberlite XAD-7 column,Sephadex LH20 column and Solid phase extraction?Oasis HLB cartridge?column.The contents of total phenols and total flavonoids in FF fraction was the highest,40.61 mg GAE/g and 148.38 mg CE/g,respectively.Total anthocyanin contents in FF fraction was the highest,that was 22.43 mg/g.Using UHPLC-ESI-HRMS/MS analysis showed that the main components of P.utilis fruits were Rutin,Isorhamnetin-3-O-rutinoside and Cyanidin-3-O-glucoside.?2?The scavenging ability of DPPH and ABTS free radicals in different fractions of P.utilis fruits showed a good dose-effect relationship with the concentration.For DPPH free radical scavenging,the FF fraction had better be as active as Vc,with an IC₅₀ value of 2.46?g/mL.For scavenging ABTS free radicals,the IC₅₀ values of TPF,FF and AF fractions were 3.45?g/mL,3.20?g/mL and 2.93?g/mL,respectively.All higher than Vc,wasn't as good as Vc scavenge effect.Different phenolic components have certain inhibitory effects on the generation of ROS in HepG2 cells induced by H₂O₂,among which FF component has the strongest inhibitory effect on the generation of ROS in cells,followed by AF component.?3?The three phenolic components of P.utilis fruits had good inhibitory effects on pancreatic lipase and?-glucosidase.The IC₅₀ values of TPF,FF and AF fractions were 423.15?g/mL,439.98?g/mL,and 407.43?g/mL,respectively,but there was no significant difference between them?p>0.05?.The three standard substances,Rutin showed the strongest inhibitory effect on pancreatic lipase,with the IC₅₀ value of 176.18?g/mL.The FF fraction had the best inhibitory effect on?-glucosidase,with the IC₅₀ value of 15.93?g/mL,and the AF fraction had the worst inhibitory effect.The inhibitory effect of Isorhamnetin-3-O-rutinoside on glucosidase was stronger than that of Rutin.Through molecular docking studies,it was found that Rutin,Isorhamnetin-3-O-rutinoside and Cyanidin-3-O-glucoside all interact with four amino acid residues of pancreatic lipase?Val 322,Ala 197,Glu 303 and His 224?.In addition,both Isorhamnetin-3-O-rutinoside and Rutin formed hydrogen bonds with the amino acid residues of?-glucosidase at Ile 440,Arg 213 and Arg 315,respectively.However,compared with Rutin,the hydrogen bonds formed by Isorhamnetin-3-O-rutinoside were shorter on average distance.?4?In the process of simulated gastrointestinal digestion,the total phenol content of P.utilis fruits increased by 1.26 times after digestion in the stomach,but decreased significantly after digestion in the small intestine.DPPH and ABTS radical scavenging showed good dose-effects with concentration,with the best IC₅₀ values of 20.05?g/mL and 27.87?g/mL after intestinal digestion,respectively.The best inhibitory effect on digestive enzymes was also found in the digested samples,whose IC₅₀ values of pancreatic lipase and?-glucosidase were 1.74 mg/mL and 1.84 mg/mL,respectively.