芽孢杆菌ZYCHH-01发酵条件优化及其抑菌物质的研究

采用芽孢杆菌ZYCHH-01发酵生产抑菌物质，以大肠杆菌（Escherichia coli）为指示菌株，通过牛津杯法测定其抑菌圈的大小判断其抑菌活性。通过单因素试验结合响应面法研究培养基pH值、发酵温度、接种量以及发酵时间对芽孢杆菌ZYCHH-01浓度和抑菌物质活性的影响。结果表明，最佳发酵条件为接种量3%，发酵温度36 ℃，培养基pH值7.8，发酵时间27.5 h。在此优化条件下，抑菌圈最大直径为21.12 mm。最小抑菌浓度为上清液稀释1∶64。生化试验结果表明，芽孢杆菌ZYCHH-01产抑菌物质对蛋白酶敏感，较耐储存，对有机溶剂和部分表面活性剂稳定，抑菌活性pH范围较大且具有良好的热稳定性，对食源性病菌抑菌活性良好。

Fermentation optimization and antibacterial substances of Bacillus sp. ZYCHH-01

Antibacterial substances were produced by Bacillus sp.ZYCHH-01 fermentation.Using Escherichia coli as the indicator strain,the antibacterial activity was determined by the size of the inhibition zone with oxford cup method.The effects of medium pH,fermentation temperature,inoculum and time on Bacillus sp.ZYCHH-01 concentrations and antibacterial substances activity were discussed by single factor experiments and response surface methodology.The results showed that the optimal fermentation conditions were inoculum 3%,fermentation temperature 36℃,medium pH 7.8 and time 27.5 h.Under the optimal fermentation conditions,the maximum inhibition zone diameter was 21.12 mm.The minimum inhibitory concentration was supernatant dilution 1∶64.The results of biochemical experiments indicated that the antibacterial substances produced by Bacillus sp.ZYCHH-01 were sensitive to proteases,storable and stable to organic solvents and some surfactants,with large pH range for antibacterial activity and better thermal stability as well as antibacterial activity against foodborne pathogens.