不同培养条件对球孢链霉菌JK-1生长及其产生抗菌物质的影响

【目的】研究不同培养条件对球孢链霉菌JK-1生长及其产生抗菌物质的影响，明确该菌生长及其产生抗菌物质的最适培养条件。【方法】在不同培养条件下分别测量球孢链霉菌JK-1的菌体干重，并以稻瘟菌为指示菌，采用菌丝生长速率法测定不同培养条件下JK-1发酵液的抑菌活性。【结果】在供试的7种培养基中，LB培养基最有利于菌体生长，PSB培养基最有利于产生抗菌物质。JK-1在10~35℃范围内均可以生长并产生抗菌物质，25℃为菌体生长和产生抗菌物质的最适温度。JK-1在PSB中培养5 d菌体干重可达最大值，培养7 d抑菌活性可达到最大值。适宜于JK-1生长及其产生抗菌物质的pH值范围为6~8，最适为pH 7。JK-1能够有效利用多种碳源和氮源进行生长和产生抗菌物质，其中分别以甘油为碳源和酪氨酸为氮源时生长最好；以麦芽糖为碳源和硫酸铵为氮源时发酵液的抑菌活性最强。【结论】球孢链霉菌JK-1生长和产生抗菌物质的最佳培养条件为pH 7的PSB培养基，25℃条件下培养7 d，甘油和酪氨酸最适于该菌的菌体生长，麦芽糖和硫酸铵最适于产生抗菌物质。

Different culture conditionséffects on growth and antifungal substances production of Streptomyces globisporus JK-1

【Objective】The effects of medium components and other culture conditions on the growth and antifungal substances production of Streptomyces globisporus JK-1 were investigated in order to determine the optimum culture conditions. 【Method】Streptomyces globisporus JK-1 was incubated under different culturing conditions to measure the cell dry weight； also， using the rice blast fungus as the indicating fungus， the mycelial growth rate method was used to determine the antifungal activity on JK-1 fermentation liquid under different culturing conditions. 【Result】The results showed that amongst the seven tested media， the best medium for fungus growth was LB and the best medium for antifungal substances production was potato sucrose broth （PSB）. For the growth and antibiotic production of S. globisporus JK-1 on medium PSB， the temperature range was 10-35℃， with the optimum temperature measured at 25℃. The cell dry weight reached maximum after 5 d of incubation and the antifungal substances production reached maximum after 7 d of incubation at 25℃. The most favorable pH range for growth and antifungal substance production was 6-8； the optimum level was measured at the pH 7. JK-1 could effectively utilize several kinds of carbon and nitrogen sources for its growth and antifungal substances production； amongst the tested sources， glycerol and tyrosine were the most favorable for growth， while maltose and ammonium sulfate were the most favorable for strong antifungal activity. 【Conclusion】The optimum culturing condition for growth and antifungal substances production of Streptomyces globisporus JK-1 was incubating the fungus at 25℃， PSB medium in pH 7 for 7 days. Also， glycerol and tyrosine were the most favorable sources for improving fungus growth， while maltose and ammonium sulfate were the most favorable sources for antifungal substances production.