Study On The Quality Standard Of The Leaves Of Alstonia Scholaris

The leaves of Alstonia scholaris is the dry leaves of Alstonia scholaris(Linn.)R.Brown(Apocynaceae),which have been historically used in "Dai" ethnopharmacy of Yunnan province of the People’s Republic of China,mainly distributed in Yunnan,Guangdong,Guangxi,Hunan and Taiwan provinces,P.R.China.The leaves of Alstonia scholaris is cold in nature and bitter in taste,which has the function of eliminating the phegm,clearing heat and relieving a cough.In folk,it is used to treat cough caused by pulmonary retention of phlegmopyrexia,expectoration,chronic bronchitis and pertussis.It contained in the "Pharmaceutical standards of Yunnan Province"(1974),"Pharmacopoeia of Peoples Republic of China"(1977,First volume)and "Standard of traditional Chinese medicinal materials in Yunnan province"(2005,Seventh volume).In recent years,chemical constituents and pharmacological activities of the leaves of Alstonia scholaris have been studied.It includes alkaloids,flavonoids,triterpene,steroid,volatile oil,vitamin etc,and alkaloids are mainly monoterpenes indole alkaloids.Monoterpene indole alkaloids have a large number of skeleton.Thus,monoterpene indole alkaloids showed various and excellent biological activity,such as those with antitumor activity of vinblastine,cerebral protective effect of vincamine,anti hypertensive effect of reserpine,promoting the release of norepinephrine of yohimbine and antidepressant effect of ibogaine and so on.A series of drugs have been successfully developed,which shows that medicine coefficient of monoterpene indole alkaloids is very high.Therefore,alkaloids from the leaves of Alstonia scholaris become a research hotspot in recent years,modern pharmacological research show that it has obvious pharmacological activities,such as antimicrobial,antiviral,anti-tumor,anti-inflammatory and analgesic,immune regulation,neuropharmacology,radioprotective effect,antitussive and antiasthmatic,and has potential medicinal value.Currently,the proprietary Chinese medicine about the leaves of Alstonia.scholaris on the market has Deng Tai Ye Pian,Dengtaiye Keli and so on.However,for a long time,the leaves of Alstonia scholaris has been the lack of scientifically and systematically evaluation of the quality standard.Pharmacopoeia of Peoples Republic of China(1977,First volume)only described its morphological characteristics,identification(no TLC),nature and taste,functions and indications,function and usage,and storage.So it is lack of systematically qualitative and quantitative indexes to control its quality standard.Therefore,we research 28 batch of the leaves of Alstonia scholaris as the object,using the modern analysis methods for qualitative and quantitative analysis,including moisture content,ash content,extractum,heavy metals content,microscopic identification,thin layer chromatography(TLC),fingerprint,the contents of total alkaloid and composition,in order to establish systematically,accurately and reliably quality standard of the leaves of Alstonia scholaris.