Wing Stem Dracocephalum Study On The Analysis Of Chemical Constituents And Biological Activity

Anaphalis sinica Hance form.pterocaula(Franch.et Savat.) Ling,also called "Bai Si Lun Feng" or "Wu Hua Cao",attributes to Anaphalis DC.of Compositae.As one of the most important traditional herbs,it is widely used in curing rheum,dysentery,enteritis,tracheitis,cholecy stitis and so on.In China,the modern studies connnect these pharmacological properties of A.sinica with the chemical components it contains,such as essential oil,flavonoids,glycosides,phenolic compounds ect.In this paper,the components of essential oils,total flavonoids,total phenolic compounds and total polysacchrides of the flowers,leaves and stems of A.sinica f.pterocaula were extracted and determined.We aslo preliminary discussed the in vitro antimicrobial and antioxidant activities of the extracts from A.sinica f.pterocaula.The main results are as follows:1.The essential oils of the leaves,stems and flowers of A.sinica f.pterocaula were obtained by hydrodistillation and analyzed by GC-MS method.As a result,twenty-two compounds were determined from flowers.The main components wereα-bisabolol(20.17%),hexadecanoic acid (9.26%) and nerolidol(6.22%).Twenty compounds were detected from leaves,and the main components wereβ-himachalene(8.71%),cedren-13-ol(7.13%) and caryophyllene(6.80%). Fourteen compounds were obtained from stems,and the main compound was pentadecane(5.95%).2.The in vitro antioxidant activities of different extracts of A.sinica f.pterocaula were evaluated.The methanol and ethanol extracts from leaves,stems and flowers of A.sinica f. pterocaula were extracted by Soxlet extraction.The total flavonoids,total phenolic contents,OH·, O₂^-·,DPPH·scavenging capacities and antioxidant protection ofβ-carotene were determined by spectrophotometric method.The results showed that the flowers contained more flavonoids than the stems and the leaves,and the total flavonoids could reach 3.86%,while,the stems and leaves contained more phenolic compounds than the flowers,and the phenolic compounds were 2.60%and 2.58%,respectively.The extracts of the flowers,stems and leaves all possessed antioxidant activities in different extent.Under these four antioxidant testing systems,it was found that in OH·, DPPH·radical-scavenging assays andβ-carotene/linoleic acid system,the antioxidant activities were decreased in the order of flower extract＞stem extract＞leave extract,while the scavenging rates of O₂^-·were decreased in the order of leave extract＞stem extract＞flower extract.3.Using the method of Oxford cup,we also examined the in vitro antimicrobial activities of various extracts of A.sinica f.pterocaula.The results showed that the methanol extract from A. sinica f.pterocaula was found to inhibit the growth of bacteria tested,including Staphylococcus aureus,Escherichia coil,Staphylococcus albus,Bacillus subtilis,Bacillus cereus and Bacillus coagulans.For the inhibition of Staphylococcus albus and Bacillus cereus,the antimicrobial activities were even better than the positive control(tetracycline hydrochloride).4.The contents of polysacchrides from stems,leaves and flowers of A.sinica f.pterocaula were 7.31%,6.71%,and 4.86%,respectively.In addition,the polysaccharides from the entire plants of A. sinica f.pterocaula possessed some antioxidant activities in O₂^-·,DPPH·radical-scavenging assays.