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期 刊 ：植物保护学报 2009年

关键词：短小芽孢杆菌；抗菌物质；提取；抑菌活性；

Keywords:Bacillus pumilus, antagonistic substances, isolation, antifungal activity,

摘 要 ：为明确短小芽孢杆菌BSH-4所产生抗菌物质的理化性质,以黄瓜菌核病菌为指示菌,采用平板打孔法研究了温度、pH变化、紫外照射、有机溶剂、金属离子及蛋白酶等对其稳定性的影响。结果表明,该抗菌物质粗提液具有良好的热稳定性,100℃处理1h后仍具有对照活性的90%左右;对酸碱较敏感,在pH值6~8时活性较高;对紫外线稳定,在紫外光下照射10h以上时,其活性基本不受影响;经乙醚和丙酮处理后仍具有对照活性的80%以上;对重金属离子敏感,Ag⁺、Cu²⁺、Zn²⁺能够降低对照活性的40%左右;对蛋白酶较稳定。此外,该抗菌粗提物同时对黄瓜蔓枯病菌、番茄早疫病菌和黄瓜立枯病菌有较高的抑制活性,具有分解羧甲基纤维素的能力,但不具有分解几丁质和β-1,3-葡聚糖的能力,并且其抗菌活性与分解羧甲基纤维素的能力无关。

Abstract:In order to determine the physical and chemical properties of the antifungal substances produced by Bacillus pumilus strain BSH-4, using agar-well diffusion method, the effects of temperature, pH values, ultraviolet, organic solvents, metal ions and protease on their antagonistic abilities against Sclerotinia sclerotiorum(Lib.)de Bary were studied. The results showed that this crude antifungal substances were thermal stable, about 90% of the initial activity remained after heating at 100℃ for 1h; they were sensitive to acidity-alkalinity, only in the pH range of 6-8 were stable; the antifungal activity was almost not be destroyed when they were under UV irradiation for 10h; when they were treated by ether and acetone, their inhibition activity remained above 80% of control; they were sensitive to heavy metal ions, Ag⁺、Cu²⁺ and Zn²⁺ ions could reduced about 40% inhibition activity of control and they were not sensitive to protease. The crude products also had good inhibitory activities on Mycosphaerella melonis, Alternaria solani and Rhizoctonia solani. They could decompose of carboxymethyl cellulose, but could not decompose of chitin and β-1, 3-glucan, and their antifungal activity had no relationship with their decomposition ability of carboxymethyl cellulose.

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