摘要
以筛选自健康桑树叶片的内生细菌多粘类芽胞杆菌(Paenibacillus polymyxa)为实验菌株,对其产脂肪酶进行分析,探讨菌株在油污废水净化领域的应用潜力。在透明圈法定性分析的基础上,研究了影响菌株产酶的因素,优化了产酶条件;采用壳聚糖-戊二醛固定的方法对脂肪酶进行固定,探讨了固定化酶对模拟油污废水的降解能力。结果表明,菌株具有产脂肪酶特性,所产脂肪酶的最适反应温度为39℃,最适反应pH值为7.0。通过碳氮源筛选发现,蔗糖(60 g/L)和菜籽饼粉(15 g/L)最适合作为菌株培养基发酵产酶。设置培养基初始pH为7.0,培养温度32℃,发酵培养2 d,脂肪酶活性即可达到最大值。脂肪酶可有效固定在壳聚糖-戊二醛载体上。降解模拟油污废水时,游离酶在反应48 h时降解度达638.88 mg/mgprot,而后持续下降;固定化酶在反应36 h时,降解度达4174.44 mg/mgprot,且在60 h内,一直保持在相对恒定的水平。60 h后,固定化酶的降解度虽然显著下降,但相比于游离酶仍然保持较高的降解能力。内生细菌多粘类芽胞杆菌具有良好的产脂肪酶及降解油污能力,在废水净化领域有潜在的应用前景。
Lipase,produced by the endophytic bacterium Paenibacillus polymyxa as experiment object isolated from healthy mulberry leaves,was analyzed to explore the application potential in the field of oil wastewater purification.Based on the qualitative analysis of lipase by transparent circle method,factors affecting the enzyme production were studied to optimize the enzyme production conditions.Chitosan-glutaraldehyde was used as a carrier to immobilize the lipase,the degradation ability of the immobilized enzyme to simulated oil wastewater was analyzed.The results showed that the strain had characteristics of producing lipase.The optimal reaction temperature was 39℃,and the optimal reaction pH value was 7.0.Sucrose(60 g/L)and rapeseed cake powder(15 g/L)were the most suitable fermentation media for the strain to produce enzyme.When the initial pH value of the medium was at 7.0,and the culture temperature was at 32℃,enzyme activity reached to the maximum after 2 days.And the lipase could be effectively immobilized on the chitosan-glutaraldehyde carrier.When degrading the simulated oil wastewater,degradability of free enzyme reached to 638.88 mg/mgprot at 48 h,and then declined.Degradability of immobilized enzyme reached 4174.44 mg/mgprot at 36 h,and remained at a relatively constant level within 60 h.After 60 hours,degradability of immobilized enzyme decreased significantly,however,it still maintained at a higher level compared to free enzyme.Endophytic bacterium P.polymyxa showed high abilities to produce lipase and degrade oil wastewater,which meant the strain had potential application prospects in the field of wastewater purification.
作者
王娜
赵文倩
张盈盈
蔡灏漾
李泽舒
褚衍亮
WANG Na;ZHAO Wen-qian;ZHANG Ying-ying;CAI Hao-yang;LI Ze-shu;CHU Yan-liang(Coll.of Biotech.,Jiangsu Uni.of Sci.&Tech.,Zhenjiang 212100)
出处
《微生物学杂志》
CAS
CSCD
北大核心
2024年第4期31-39,共9页
Journal of Microbiology
基金
江苏科技大学博士启动基金项目(1102931901)。
关键词
内生细菌
脂肪酶
多粘类芽胞杆菌
固定化
油污废水
endophytic bacterium
lipase
Paenibacillus polymyxa
immobilization
oil polluted wastewater
