Study On Allelopathy And Identification Of Water-soluble Allelochemicals Of Angelica Sinensis(Oliv.) Diels

In this study, we collect the eluent of Angelica sinensis(Oliv.) Diels by the method simulating natural rain. By using Brassica campestris L., Trifolium Linn L. as receptor, Allelopathy were studied by measuring the seedling growth and the root growth. The eluent of Angelica sinensis(Oliv.) Diels tested the existence of allelopathy. And the Allelochemicals were identified. The main research results were as follows:(1) The eluent of Angelica sinensis(Oliv.) Diels tested the existence of Allelopathy on Brassica campestris L. and Trifolium Linn L.. The inhibition increased as the concentration of eluent increased, and root length on which the performance of Allelopathy was more sensitive. As Brassica campestris L. for example, when the eluent concentration of O.D.260=4, the inhibition of rape root length was reached57.76%. But with the reduced of eluent concentration, allelopathic inhibition gradually disappeared, the Allelopathy even changed into stimulating effect. So maybe there were different Allelochemicals in the eluent or there were different Allelopathy when the concentration of Allelochemicals changed.(2) We divided the eluent into two parts:the soluble fraction of methanol and the-insoluble part. The two parts be tested the existence of allelopathy by Bioassay.(3) The soluble fraction of methanol was analyzed with GC-MS. Four groups of eleven kinds of material were identified, it contained Long Chain Fatty Acids, Coumarins, Aldehydes and Anilines. The main components were Oleic Acid, Palmitic Acid and Hexadecenoic Acid, their relative amounts were19.8%,17.3%and12.0%. Secondly a kind of Benzaldehyde and a kind of Aniline were identified, their amounts were2.5%and2.7%respectively.(4) The methanol-insoluble part of the eluent was dissolved in water, and it isolated by DEAE cellulose column. We found that the fraction of0.05mol/L NaOH appears brown precipitation in the pH4. Through the pH depositing and Thin Layer Chromatography method, we get a single material. Bioassay showed that the material have Allelopathy. The material contents of12.85mg/g DW in Angelica sinensis and0.09mg/g DW in rhizosphere soil through extracted totally by alkali.(5) Structure of the material was identified. The material in256nm place has the absorption peak and E0.1%256=14.92. Infrared Spectral analysis and chemical method identified the molecule containing carboxyl and phenolic group. Element analysis shows that the carbon content of46.57%, the hydrogen content of5.57%and the nitrogen content of10.7%in the material. Mass Spectrometry method determined the relative molecular mass of this material for333.