Studies On Chemical Consituents And Biological Effect Of Cynanchum Bungei Decne.

The Cynanchum bungei Decne. is the plant of Asclepiadaceae Cynanchum Linn., it has three varietes of which are Cynanchum bungei Decne., C. auriculatum Rogle ex Wight and C.wilfordii Hemsl. Among them, C. auriculatum Rogle ex Wight and C.wilfordii Hemsl are mainly planted in the coastal areas of Jiangsu province, and are widely investigated, now they have both been planted over a large area. The Cynanchum bungei Decne. is Hard-earned, as a result, there is less research about chemical composition and biological activity on it. The Cynanchum bungei Decne. tases bitter and sweet astringent, is slightly warm in nature and is nonvenomous. It has been used traditionally as a tonic of blood benifis, bone strongness and stamach healthy. And it also has been used for the treatment of theumatic pain, dyspepsia, weakness of kidney, stamach and liver. It was found to show various bioactivies of immunity enhancing and radical scavenging in morden studies. It has therapeutic effects in the weakness caused by long time sickness, white hair in the early age, anemia, soreness and weakness of waist and knees, neurasthenia, chronicity migratory arthralgia, haemorrhoids, yin deficiency and chronic malaria, intestinal hemorrhage, long period ulcer and so on. Fresh Cynanchum bungei Decne. can also exhibit the effect of loosening bowel to relieve constipation thus applied in the constipation of elderly. This article did a systematic research on the chemical constituents of the Cynanchum bungei Decne., consummated the material basis of the Cynanchum bungei Decne and screened the anti-oxidant activity of the isolated monomer, investigated the mechanism of the active component in clearance of the ree radicals.Methods 6.7kg of the Cynanchum bungei Decne. was extracted by the method of reflow by 80%, 60% and 60% ethanol, respectively, the reflow time was 0.5, 1 and 1h, then the mixture was filtrated. The extract was got by concentrating the filtrate. The extract was suspended by adding water to it and the suspension was abstracted by petroleum ether, dichloromethane and acetic ether, respectively, and each experiment was carried out for three times to get the ligarine part, the dichloromethane part the acetic ether part and the mother liquid of the water layer. Each part was further depurated by the means of silica gel column chromatograph, Sephadex LH-20 column chromatograph, ODS column chromatograph, preparation HPLC column chromatograph and recrystallisation. The configuration of each monomers obtained was assessed by the technology of MS, IR, UV, 1H-NMR, 13C-NMR, and the two-dimensional spectrum according its physic-chemical property and the reports of reference documents. At the same time, the hydroxybenzene acetophenones and the analogue enriched in the Cynanchum bungei Decne were collected for the biological activity effect.DPPH(1,1-diphenyl-2-picrylhydrazyl) method was used to mimic the in vitro simulated free radical oxidation process. Vitamin C(a traditional antioxidants) was employed as a control, the hydroxybenzene acetophenones solution and the analogue solution were prepared in different concentration and reacted with the DPPH solution for the same time period. The absorbance was determined to get the clearance and the concentration linearity curve, the IC50 value of the DPPH clearance of the compounds was calculated to decide the anti-oxidizing ability of different compounds. The rationale of the anti-oxidizing activity of hydroxybenzene acetophenones and analogue was implicated in combination with the construction features of the compounds.Results 12 compounds were obtained from the separation of the Cynanchum bungei Decne, and were identified as follows: β-sitosterol(1),p-Hydroxyacetophenone(2),2,4-Dihydroxyacetophenone(3),2,5-Dihydroxyacetophenone(4),m-Hydroxyacetophenone( 5), Baishouwuhenzophenone( 6),2,6,2′-trihydroxy-3-acetyl-4′-(2′′,6′′-dihydroxy-3′′-acetyl)phenyl-6′-methyl-benzophe-none(7),Betulinci acid(8),Hydroquinone(9),Succinic acid(10),Eleutheroside A(11),Bungeiside-C(12)。 Among these compounds the m-Hydroxyacetophenone(5) was first separated from the plant.The anti-oxidizing ability was tested by DPPH method and the IC50 value of the compounds were calculated after the data collection. According to the result the anti-oxidizing ability was listed as follows:Vc>hydroquinone>2,5-Dihydroxyacetophenone>Baishouwuhenzophenone>>2,4-Dih ydroxyacetophenone >2,6,2′-trihydroxy-3-acetyl-4′-(2′′,6′′-dihydroxy-3′′-acetyl)phenyl-6′-met hyl-benzophe-none> m-Hydroxyacetophenone. The ability of acetophenones to remove the DPPH free radicals was mainly because of the contrapuntal hydroxyl group on the benzene ring, and also because of the amounts of the hydroxyl group.Conclusion 12 compounds were dissected from the ethanol-aqueous extract of Cynanchum bungei Decne, among which the m-Hydroxyacetophenone(5) was first separated from this genera of plant. In addition, the anti-oxidant ability of the obtained compounds was also tested, the structural agent on the anti-oxidant ability of the hydroxybenzene acetophenones was implicated, the result of which has established the groundwork of the development and utilization of the Cynanchum bungei Decne and cynanchum plant.