Antimicrobial activities and chemical constituents of Indigofera amblyantha Crai

By associated ultrasonic extracting method，the different parts of Indigofera amblyantha Craib extracts were prepared with petroleum，chloroform，ethyl acetate，acetone and methanol，respectively. The fungistatic activities were detected against fungi including Magnaporthe grisea（Hebert）Barr，Fusariumoxysporum f. sp. Vasinfectum （Atk.）Synder et Hansen，Fusarium graminearum Schw.，Sclerotinia sclerotiorum（Lib.）de Bary，Venturia pyrina. The results showed that the root and seed extracts had medium bioactivities，but the stem and leaf extracts had no bioactivity. The antifungal activity of root extracts was lower than that of seed extracts. Moreover，antifungal activity of root extracts increased with the polarity of extraction solvents increasing. The antifungal activity of methanol extracts of root was the strongest，the antifungal activities on above fungi were 65.31%，69.09%，72.50%，61.06% and 64.95%， respectively. However，petroleum ether extracts showed the strongest bioactivity in all seed extracts，and the antifungal activities on above fungi were 71.43%，72.73%，79.04%，74.34%，74.02%，respectively. The antibacterial activities of extracts were also assessed against bacteria（Ralstonia solanacearum，Escherichia coli）using disc method. The results showed that petroleum ether extracts of seed had medium activity，the means of inhibition zones of the above two bacteria were 1.45 cm and 1.41 cm，respectively. No others showed activities. The result of Gas Chromatography- Mass Spectrometer（GC-MS）analysis indicated that 17 compounds，according for 99.065% of total，were present in the petroleum ether extracts of seed，and linoleic acid （37.569%）was the major chemical constituent