Studies On Principal Phytochemical Composition And Biological Activities Of Cili Fruit

Cili(Rosa roxburghii Tratt)belongs to the Rosa genus of Rosaceae family,its fruit is highly nutritious with high medical and commercial value.Owning to high content of various phytochemicals including organic acid,polysaccharide,vitamins,flavonoids,triterpenoid,Cili fruit has been known to have numerous beneficial actions on aging,cancer,cardiovascular and other chronic disease.Present research aimed at measuring the content of the hydroalcoholic phytochemicals including phenolic compounds,flavonoids,and triterpenoids of Cili fruit,evaluating the antioxidant and tyrosinase inhibitory activity of Cili fruit,and identifying the main bioactive phytochemicals of Cili fruit,so as to discover the hidden potential of this valuable fruit.The main research conclusions are as follows:(1)Obtain the optimum conditions of ultrasonic-assist extraction of Cili phenolic compounds by response surface method.Box-Behnken response surface analysis demonstrated that the optimum conditions for extracting phenolic compounds from Cili fruit were 28-fold volume of 59%aqueous ethanol solution,ultrasonic temperature of 54 ℃ and extraction time of 1.92 h,the predicted value is 15.78%,and reliability of the model is 99.02%.(2)The content of bioactive phytochemicals,antioxidant activity and tyrosinase inhibitory activity of the hydroalcoholic extracts of Cili fruits were determined.The phenolic content of Cili are 129.26-154.81 mg/g DW,flavonoid content of Cili are 8.76-11.55 mg/g DW,triterpenoid content of Cili are 21.0-30.3 mg/g DW.Cultivated Cili showed the higher phenolic and triterpenoid content than the wild,wild Cili showed the higher phenolic and triterpenoid content than the cultivated,yellow Cili showed higher phenolic content,green fruits showed higher content of flavonoid and triterpenoid.Cili fruits from different cultivars and maturity stages all demonstrated as good antioxidant agents and tyrosinase inhibitors,with IC50 value of DPPH scavenging activity 10 μg/mL,twice of the positive standard,IC50 value of ABTS scavenging activity 0.3 mg/mL,fifteen times of the positive standard,FRAP value 135.33-199.96 mg FeSO4/100 g DW,twentieth of the positive standard,IC50 value of tyrosinase inhibitory activity 0.17-0.20 mg/mL,about triple of the positive standard,demonstrating the great potential of Cili fruit as good source of antioxidants and tyrosinase inhibitors.(3)Identify main bioactive compounds of Cili fruits by LC-MS.Nineteen compounds,mainly ellagic acids and its derivatives,flavonoids and their glycosides were identified by UPLC-Triple-TOF/MS analysis,among them,9 compounds were identified by comparing with authentic standards.