Studies On The Chemical Constituents Of Two Medicinal Plants And Their Biological Activities

This thesis studied two medicinal plants,Taraxacum mongolicum Hand.-Mazz.and Zingiber officinale Rosc.Herba Taraxaci,which has a long history as a Traditional Chinese Medicine, has different species as well as rich resources in China.Among which,the most popular species is Taraxacum mongolicum.Previous phytochemical examinations on this genus were concentrated on Taraxacum officinale.In order to find out the active components of T.mongolicum,its phytochemical purification was performed and 26 compounds were isolated and structurally elucidated. Compoundsâ… -12 andâ… -13 were isolated from Taraxacum species for the first time. Compoundsâ… -17 andâ… -18 were isolated from T.mongolicum for the first time.It can be seen from the above results,the flavonoids and phenolic acids are the main metabolisms of Taraxacum mongolicum.The in vitro cytotoxicity investigation on these constituents from mongolicum was also carried out.Compoundsâ… -2 and I-10 showed strong inhibitory action to tumor cells.Zingiber officinale is a plant belonging to Zingiber genus of Zingiberaceae. In Traditional Chinese Medicine(TCM),it is considered as a pungent,dry, warming,yang herb to be used for ailments triggered by cold,damp weather.To make a better use of Zingiber officinale,we studied on the chemical constituents and antioxidant activities of the material bought in luoping county,Yunnan province.9 compounds were isolated and structurally elucidated.Compoundâ…¡-3 showed strong antioxidant activity.