Studies On Material Basis For Analgesic And Anti-inflammatory Of Rubus Multibracteatus Levl&vant

Objective: Rubus multibracteatus Levl.&Vant is widely distributed in southwest China,which has been used for a long time in Miao to treat cold,fevers,dysentery and epistaxis. It was found that the active constituents in Rubus were abundant, including flavonoids,terpenoids,volatile oil, which possess diverse bioactivities, such as analgesic, anti-inflammatory and antioxidant activities.However,its pharmacological activities and constituents are not yet clear. This work investigates the analgesic and anti-inflammatory activity of petroleum ether,ethyl acetate,n-butyl alcohol, residual fractions and 80%ethanol extracts of the leaves of the Rubus multibracteatus Levl.&Vant. This work epecially focused on the extraction and isolation of compounds functioned as analgesic and anti-inflammatory activity which would provide a theoretical basis for the development of Rubus multibracteatus Levl.&Vant.Methods: The peripheral analgesic activity of different extracts of Rubus multibracteatus Levl.&Vant was evaluated by the acetic acid induced writhing test and the central analgesic action was assessed by hot-plate test in mice. The dimethylbezene-induced ear edema test is suitable for evaluation of anti-inflammatory activity. Five groups of animals(n=10) were orally administered with 80%ethanol,petroleum ether,ethyl acetate,n-butyl alcohol and residual fractions of Rubus multibracteatus Levl.&Vant(428.6 mg/kg) to evaluate the analgesic and anti-inflammatory activity. The positive group of animals(n=10) were given indomethacin(10 mg/kg,i.g),morphine(10 mg/kg,s.c),respectively.some active chemical compounds functioned as analgesic and anti-inflammatory activity were isolated by means of silica gel column chromatography,Sephadex LH-20 and recrystallization.Results: Et OAc fraction and n-butyl alcohol fraction have marked analgesic and anti-inflammatory activity.Intensity of analgesic activity: n-butyl alcohol fraction > Et OAc fraction > petroleum ether fraction. Intensity of anti-inflammatory activity: Et OAc fraction>n-butyl alcohol fraction>petroleum ether fraction. Et OAc fraction were isolated by means of silica gel column,Sephadex LH-20 and recrystallization. According the spectral data of 1H-NMR and 13C-NMR, Four compounds isolated from Rubus multibracteatus Levl.&Vant were elucidated as: β-sitosterol(Rc1), olenaolic acid(Rc2), kaempferol(Rc4),quercetin(Rc5). All compounds were first reported from this plant.Conclusion: Et OAc fraction and n-butyl alcohol fraction are the main efficacy parts of Rubus multibracteatus Levl.&Vant for analgesic and anti-inflammatory. By studying the research has a further understanding of chemical composition of Rubus multibracteatus Levl.&Vant. The results revealed the fundamental substance initiatory and provided the effective basis for rationally development and application.