一株耐盐嗜热菌Aneurinibacillus thermoaerophilus H7的分离及其油脂降解特性

针对高盐、高油餐厨垃圾高温堆肥功能菌株缺乏的问题,以大豆油为唯一碳源,通过测定生物量、脂肪酶活性和油脂降解率,从餐厨垃圾堆积处的土壤样品中分离筛选出一株嗜热油脂降解菌H7.通过形态特征、生理生化特征和16SrDNA序列分析,对筛选的菌株进行鉴定,考察其耐盐能力、油脂降解和生长特性.结果表明,菌株H7为嗜热嗜气解硫胺素芽孢杆菌(Aneurinibacillus thermoaerophilus),最高耐盐浓度为30 g/L.菌株H7在油脂浓度为15 g/L的发酵培养基中发酵72 h,油脂降解率为60.11%,菌体浓度OD600为1.88,脂肪酶活性为11.65 U/mL.菌株H7可生长的温度为40-60℃,pH值为5-8,摇床转速为120-240 r/min,最适生长的温度为50℃,pH值为6,摇床转速为220 r/min.本研究获得了具有耐盐性和能降解高浓度油脂的嗜热菌株H7,可为高盐高油脂含量的餐厨垃圾堆肥提供微生物菌种资源.(图8表2参34)

Isolation and oil degrading characterization of a halotolerant thermophile Aneurinibacillus thermoaerophilus H7

In order to obtain functional microorganisms used for thermophilic composting of food waste with high salt and oil content, the aim of this study was to isolate a halotolerant thermophile with the ability to efficiently degrade oil. Soybean oil was used as the sole carbon source to isolate oil-degrading microorganisms. A strain with the highest oil-degrading ability was identified based on morphological, physiological, and biochemical characterization and 16 S rDNA sequencing. The salt tolerance and oil degradation characteristics of the isolated strain were investigated. The effects of culture temperature, initial pH, and rotation speed on the growth of the strain were tested. The isolated strain H7 was identified as Aneurinibacillus thermoaerophilus with a maximum salt-tolerant concentration of 30 g/L. When H7 was cultured in fermentation medium with an oil concentration of 15 g/L for 72 h, the oil degradation rate was 60.11%, the biomass(OD600) was 1.88, and the lipase activity was 11.65 U/mL. The optimal growth temperature, pH, and rotation speed was 50 ℃, 6, and 220 r/min, respectively. The halotolerant thermophile H7 obtained in this study provided microbial resources for thermophilic composting of food waste with high salt and oil content.