解淀粉芽孢杆菌HRH317抑菌物质发酵条件的优化

摘要

The fermentation conditions of antibacterial substances-producing Bacillus amyloliquefaciens HRH317 were studied.First of all,the effect of fermentation time,temperature,initial pH,inoculum,inoculation age,rotating speed and liquid volume on the antibacterial activity of fermentation broth were researched by single factor experiments.Then the results were optimized by orthogonal experiments,and it determined that the inoculation age,inoculum and fermentation time were the three key factors influencing the inhibition zone diameter.On the basis,the results were analyzed by Box-Behnken design and response surface methodology.At conditions of fermentation temperature 37 ℃,initial pH 7,rotating speed 150 r/min and liquid volume 30 ml/100 ml,the optimum fermentation conditions of strain HRH317 for antibacterial substances production was inoculation age 21 h,inoculum 3.8％ and fermentation time 25.5 h.According to the test model,the inhibition zone diameter of antimicrobial substances increased from 18.63 mm to 22.95 mm,increasing by 23.19％.%该试验研究解淀粉芽孢杆菌HRH317抑菌物质的发酵条件.首先采用单因素试验研究发酵时间、温度、初始pH、接种量及菌龄、摇床转速、装液量对发酵液抑菌活性的影响,然后采用正交设计对这7个因素进行筛选,分析极差结果确定接种菌龄、接种量、发酵时间为影响抑菌圈大小的3个关键因素,在此基础上,采用Box-Behnken设计及响应面进行分析,在发酵温度37℃、初始pH7.0、摇床转速150 r/min、装液量30 mL/100 mL条件下,确定菌株HRH317抑菌物质的最佳发酵条件为接种菌龄21h、接种量3.8％、发酵时间25.5 h.拟合试验模型结果显示,抑菌活性物质的抑菌圈直径大小从未优化前的18.63 mm提高至22.95 mm,抑菌圈大小增加23.19％.