Abstract: In order to investigate the characteristics for separation and identification of the antifungal substance produced by antagonistic Streptomyce lydicus A02,the methods of pH paper chromatography,paper electrophoresis,organic solvent extraction,silica gel TLC,Doskochilova solvent system paper chromatography,ultraviolet spectrum scan,functional group and proteinase test were respectively used to determine the ion property,the polarity,the ultraviolet absorption character,the main functional groups and the sensitivity to proteinases of the bioactive substance of strain A02.The results showed that the antifungal substance were electrically neutral and highly polar in solutions,which enabled it to be efficiently extracted with n-butyl alcohol as the extractant and separated by TLC with ethanol + aqua ammonia + water(8∶ 1∶ 1,V/V) as the solvent combination.Its antifungal activity was not affected by proteinase K and trypsase.There were functional groups of unsaturated alkyl,saccharide or glycoside,amino acid and aldehyde in its structure according to the chemical reactions.Doskochilova paper chromatographic pattern and ultraviolet absorption spectrum of the antifungal substance were in accordance with the characters of tetar-alkene macrolide antibiotic.The combination of the information referred to above reveal a new biological function for S.lydicus to produce tetar-alkene macrolide antibiotics.

Key words: Magnaporthe grisea, Pathogenicity, Population structure, Variation

CLC Number: 

• S435．111． 4 + 1