Chemical Constituents Of Portulaca Oleracea L.and Antifeedant Activity To Spodoptera Litura

Portulaca oleracea belongs to Portulacaceae,which is not only served as a vegetable in south China,but also use as a traditional Chinese medicine to cure many diseases in clinic,especially on anti-aging,anti-tumor,antibacterial and other ailments,such as the disease of gastrointestinal and cardiovascular system.Botanical pesticide has many advantages,such as security,environmental protection,more bioactivities,and insect do not easily resistance to drugs.Therefore,many researchers has been focus on this area and found out many botanical pesticide.Evidences have showed that whole plant of P.oleracea can be used as pesticide.However,there weren't any report that insect-resistant or antifeedant chemical constitutes isolated from P.oleracea.To exploit compounds of antifeedant and toxicity activities on P.oleracea,this project used Spodoptera litura as target pest,active compounds were isolated by technology of silica gel,sephadex LH-20,HPLC,and identified by NMR.The main results and conclusions as below:1.Those insects of treatments of concentrations 10,5%,3% of ethyl alcohol extraction of P.oleracea was showed negative growth on first day.Concentrations of 1% and 0.5% can delay growth of insect,also,concentrations of 10,5%,3% 1% and 0.5% is extremely significant than control after first day,whereas 0.1% has nothing effect on insect.2.Petroleum,ethyl acetate,n-butyl alcohol,and water extracts were fed to S.litura larva of three instars by concentration 10%,constantly weigh four days.The results has showed that the treatment of petroleum or ethyl acetate extracts larva were lose weight and many larva were died after ate fodder,n-butyl extract can lose weight but no any larva was died,and water extract has no affect on larva.Antifeedant activity of all extracts were extremely significant than control.3.Petroleum extract of pursalne was isolated by silica gel column,sephadex LH-20,and semi-pre HPLC,4 compounds were isolated and identified by NMR and HR-EIS-MS,There were fatty acid(1),portulacanone A(2),portulacanone D(3),portulacanone C(4).Antifeedant activity made by two compounds,that is compound 1 and compound 2.4.The principal component analysis results of Nanping,Haikou,Danzhou,Ledong,Hainan,and Ledong,Hainan,are different from those of other regions and are not related to each other;Jixi in Heilongjiang,Qianxian in Shaanxi,Tieling in Liaoning,The principal component analysis results of Xuzhou in Jiangsu province are different from the general areas,but they are close to each other,and the results of principal component analysis in other regions are all clustered together,indicating that the principal components of them are similar.5.The results of principal component analysis of P.oleracea in October were different from those in other months,but the principal components in November were similar.6.The content of active compounds in P.oleracea has no obvious relationship with the density and quantity distribution of pests.7.The repellent effect of P.oleracea on Spodoptera litura.The isolated active compounds from P.oleracea,not only can enriched green,environment protecting and pollution-free pesticide for agriculture,but also can explain why other crops plant with P.oleracea can avoid being eaten by pests.Providing more technology for cheaper plant P.oleracea.