生防菌株CAB-1抑菌物质产生的条件及其稳定性研究

目的]探索生防菌株CAB-1的最优培养条件及其产生的抑菌物质稳定性。方法]以黄瓜灰霉菌为靶标,分别采用改进牛津杯法和含药平板法测定抑菌物质活性,并对菌株CAB-1产生抑菌物质的发酵条件及抑菌物质特性进行了研究。结果]菌株CAB-1产生抑菌物质的最适培养基为4号培养基,最佳发酵温度为31℃,最佳发酵时间为48h。菌株CAB-1所产的抑菌物质在60℃及其以下具有热稳定性;超声波（100W）处理20min对抑菌物质的活性没有影响,处理30min以上抑菌物质的活性显著下降;紫外线照射20、30、40min对抑菌物质的活性没有显著影响,照射50min后其活性显著降低;pH值为6、10、11时,抑菌物质的活性最高。结论]该研究为利用生防菌株CAB-1开发新型微生物杀菌剂提供了依据。

Research on the Producing Condition and Stability of Antifungal Substance from Bio-control Bacterium Strain CAB-1

Objective] The aim was to explore the optimum culture condition for bio-control bacterium CAB-1 and the stability of antifungal substance produced by it.Method] With Botrytis cinerea as target,the activities of antifungal substance were determined by using improved Oxford cup method and medicine-contained plate process resp.The fermentation condition for strain CAB-1 producing antifungal substance and the characteristics of the antifungal substance were researched.Result] The optimum medium for strain CAB-1 producing antifungal substance was medium No.4,its optimum fermentation temperature was 31 ℃ and its optimum fermentation time was 48 h.The antifungal substance produced by strain CAB-1 possessed heat stability under and at 60 ℃.Ultrasonic treatment at powder of 100 W for 20 min had no influence on the activity of antifungal substance and its activity was decreased significantly when the ultrasonic time longer than 30 min.Ultraviolet irradiation for 20,30 and 40 min had no significant influence on the activity of antifungal substance and its activity was decreased significantly when the irradiation time was 50 min.When pH value was 6,10 and 11,the activity of antifungal substance was highest.Conclusion] This research provided foundation for developing new type of microbial germicidal agent by utilizing bio-control bacterium strain CAB-1.