Studies On Chemical Composition And Antioxidant Activity Of Ethyl Acetate Of Mongolian Drug Rubus Corchorifolius L.f.

Pearl pole,the Mongolian name of "Gandagari",is the dried stem and branch of Rubus sachalinensis Leveille,a rhizome of Rosaceae library page.It is one of the commonly used Mongolian medicinal materials and has the effects of perspiration,cough relief,exterior relief,and regulating Qi.In this paper,the chemical constituents in the Pearl pole of Mongolian medicine were separated and identified,and the trace elements were determined at the same time.The research contents are as follows:(1)The petroleum ether layer,ethyl acetate layer and n-butanol layer of Mongolian medicine Pearl rod were prepared by 75%ethanol reflux and extraction method.Antioxidant activity was detected by ABTS,DPPH and FRAP,respectively.The highest clearance rates were 81.48%for petroleum ether layer,90.52%for ethyl acetate layer and 87.43%for n-butanol layer in the ABTS method experiment.The highest clearance rates in DPPH experiments were 25.47%in petroleum ether layer,53.71%in ethyl acetate layer and 42.90%in n-butanol layer.Ferric ion reduction capacity values in FRAP method experiments were 1.20 in petroleum ether layer,2.56 in ethyl acetate layer and 2.38 in n-butanol layer.Therefore,the antioxidant capacity is ethyl acetate layer>n-butanol layer>petroleum ether layer.(2)The ethyl acetate layer of Pearl pole was separated and purified by silica gel column chromatography;medium pressure preparative liquid chromatography and high performance liquid chromatography.Ten compounds were identified by NMR spectroscopy and literature,respectively:(1)4-hydroxy-3,5-dimethoxy-benzaldehyde,(It was the first time that the compound was isolated from the Rubus sachalinensis Leveille).(2)6,7-dimethoxy-8-hydroxycoumarin,(3)3-ethyl-3-hydroxy-diethylglutarate,(4)3,5-dimethoxy-4-hydroxy-1-(1,2,3-trihydroxypropyl)benzene,(5)3-methoxy-5-hydroxy-1-(1,2,3-trihydroxypropyl)benzene,(6)6-(3-propanoyl)-6',8-dimethoxy-3'-hydroxyisoflavane,(7)beta-sitosterol,(8)2,3-trihydroxypropyl)4-dimethoxyphenol,(9)gallic-acid,(10)salicylic-acid.Among them,compounds 4 and 5 have certain antioxidant properties.(3)A method for the determination of trace elements in Mongolian medicine Pearl poles was established.Dissolution with nitric acid and determination of 10 trace elements by atomic Flame Absorption Spectrometry:K:6.5?g/g?Na:1.7×10-1?g/g?Fe:1.3×10-1?g/g?Zn:2.6×10-1?g/g?Mg:1.21 ?g/g?Mn:1.4×10-1?g/g?Ca:3.02×10 ?g/g.The recovery of each element is between 92%and 105%.The above experiments provide experimental basis and theoretical basis for the future research of Mongolian medicine Pearl pole in chemistry and medicine.