Studies On The Pharmacologically Active Ingredients And Quality Control Of Caulis Akebiae

Caulis Akebiae is a widely used Chinese medicinal herb. Caulis Akebiae is prepared from the dry stems of Akebia quinata (Thunb.) Decne, Akebia trifoliata (Thunb.) Koidz and Akebia trifoliata (Thunb.) Koidz. var. australis (Diels) Rehd. As a tradition Chinese medicine, Caulis Akebiae has been used for thousands years, the record can trace back to the tang Dynasty. It is mainly used for diuresis and lactogenesis, it also has anti-inflammatory effect, and recent years it's reported Caulis Akebiae also has anti–cancer avtivity and it is used for scores of Chinese patent drugs , such as bolus of gentian for purging liver-fire, fire-inducing power etc.Caulis Akebiae is supposed to bring to a great height of development, However, the application of confounding species of Caulis Akebiae is very serious and hamper the ues of Caulis Akebiae. At first, Guan Mutong (Caulis Aristolochiae Manshuriensis) produced from Northeast China was used as Caulis Akebiae, because the aristolochic acid that it contains has renal toxicity, the State Food and Drug Administration of China bans the use of Guan Mutong in 2002, it directly leaded to the mistrust of Caulis Akebiae. And now, Chuan Mutong (Caulis Clematidis Armandii) is used as Caulis Akebiae widely because of having similar pharmacological actions with Caulis Akebiae, but there is significant difference between them in the chemical constituents and the way of ues. In addtion, the quality of the drug display considerable variation, the effect can not be guarantee. Previous studies on the quantitative analysis and pharmacology in Caulis Akebiae are insufficient, the method of content determination included in Chinese Pharmacopoeia is too cumbersome for quality inspection professionals to handle it stably. In order to use Caulis Akebiae effective and safety, determination of the active fraction and development of quality evaluation of Caulis Akebiae is imperative.It has been reported that Caulis Akebiae contains saponins that have the glycosides of oleanolic acid and hederagenin, phenylethanoid glycosides and lignan glycosides.In this study, 6 compounds was isolated and identified. Inchluding 2 sponins, 1 phenylethanoid glycoside and 1 lignan glycoside.Though the diuretic and anti-inflammatory effects of Caulis Akebiae have been confirmed, till now no studies on which chemical composition is the major activity fraction. In the present study we investigated the effect of saponins fraction, as well as saponin-free fraction mainly contains phenylethanoid glycosides and lignan glycosides on diuresis and anti-inflammatory in normal mice, and confirm the saponin fraction is the major activity fraction.Previously, many methods have been used for the quality evaluation of Caulis Akebiae by HPLC-UV, but because of the poorly UV absorbing of saponins, it contained trivial procedures to remove other needless compounds in those methods, Therefore, an efficient, low-cost, and reliable method needs to be developed for the quality evaluation of Caulis Akebiae. In recent years, evaporative light scattering detectors (ELSD) is increasingly used to determine non- or poorly UV absorbing compounds such as saponins in TCMs, thus, in the present study a high-performance liquid chromatography coupled with evaporative light scattering detectors (HPLC- ELSD) method was established for the quality evaluation five major saponins: mutongsaponin B (1), Norarjunolic acid (2), Akebiasaponin PJ1 (3), Scheffoleoside A (4), Asiaticoside (5).Though a systematic study on methodology on the analysis method, The estiblished HPLC-ELSD method has showed good precise, stabilities and accuracy for the quantification, can be successfully applied for the simultaneous determination of five saponins in different Caulis Akebiae. Through those experiments, it is obvious that the content and composition of saponins were highly variable in different species because of the difference in cultivating conditions and genetic source, because A. trifoliata var. australis is variety of A. trifoliata, the difference between A. trifoliata var. australis and A. trifoliata is slighter than the difference A. quinata and them. In general, the result showed that: most of A. trifoliata var. australis and A. trifoliata contained all or part of 5 saponins, A. trifoliata var. australis and A. trifoliata produced in Hubei province and Henan province respectively contained none of those saponins, and so was the A. quinata produced in Fujian province. An A. trifoliata produced in Zhejiang province had the highest content of total saponins. This method is the benefit of the regulate the market of Caulis Akebiae. Ensure the safe and standard use of Caulis Akebiae.On the basis of these experiments, we found that it's said that all Caulis Akebiae contains saponins, however, the structure and quantity of saponin had great difference in different species. In additional it was hard to obtain authentic Caulis Akebiae in drug stores, and even in wholesale markets. It was strongly recommend to estiblish respective quality control for three kinds of medicinal materials used as Caulis Akebiae.