酵母菌0732-1产生的抑细菌物质特性研究

Characteristics of antibacterial substance produced by the yeast strain 0732-1

哈密瓜细菌性果斑病是近年来暴发流行的一种瓜类病害，也是我国对内对外检疫性重大植物病害。该病由燕麦嗜酸菌西瓜亚种（Acidovorax avenae subsp．citrulli，Aac）引起，具有发病快、危害广、损失重、防治难的特点，一旦发生往往给瓜产区造成严重经济损失。

Bioactive metabolites produced by Pichia anomala 0732-1 displayed significant antibacterial activity to Acidovorax avenae subsp, citrulli （Aac） which caused bacterial fruit blotch. The antibiotic capacity, antibac- terial activity and stability of crude antagonistic extract of P. anomala 0732-1 were tested and the active sub- stances were isolated. The results showed that the antibacterial material was not sensitive to ultraviolet radiation and temperature, and it was stable at pH 〈 9. The antibacterial material was purified by precipitation with （NH4）2SO4 （10%-100%, w/v）, extraction with benzene, acetone, chloroform, phenixin, ethanol and ethyl acetate, and distillation method. However, it could not be purified by precipitation with （NH4 ）2 SO4 or by extraction with organic solvent. It could be partially distilled out by distillation. In addition, antibacterial substances produced by P. anomala 0732-1 had significant inhibitory effect against Hami melon seed infested by Aac （bacterial suspension 1×10^8 CFU/mL）. When infected seeds were treated with crude antagonistic extract of P. anomala 0732-1 for 120 min, the seeding disease index was 1.67 during the cotyledon. This study suggested that P. anomala 0732-1 had the potential to be developed as an antagonistic agent for control Hami bacterial fruit blotch.