预水解发酵碳源对铜绿假单胞菌NY3产鼠李糖脂特性及应用效能的影响研究

Effect of Prehydrolysis of Fermentation Carbon Source on Characteristics and Application Effectiveness of Rhamnolipids Produced by Pseudomonas aeruginosa NY3

发酵碳源对铜绿假单胞菌NY3(Pseudomonas aeruginosa NY3)产鼠李糖脂(Rhamnolipids,Rha)的特性影响较大。研究了利用废弃动物油作为发酵碳源时,其碱预水解和酶预水解对NY3菌发酵产鼠李糖脂产量、产物结构和性能的影响,从碳源水解酸值与水解产物、鼠李糖脂组分结构和实际应用效果进行了研究。碱、酶预水解实验发现,碳源酸值由初始的19.81 mg/g分别提高到72.04 mg/g和73.75 mg/g,气质联用(GC-MS)分析检测结果表明,碱、酶预水解后,碳源均释放7种C14-C18碳链的脂肪酸,鼠李糖脂产量由未预水解的8.28 g/L分别提高到15.35 g/L和17.63 g/L。液质联用(LCMS-IT-TOF)分析结果表明,用未预水解及碱、酶预水解碳源发酵时,NY3菌所产鼠李糖脂中单糖脂含量分别为62.07%、65.67%、87.32%。利用NY3菌在中试条件下处理高浓度石化企业油污泥,发现鼠李糖脂能促进NY3菌去除油污泥中的石油烃,且促进作用强弱顺序为未预水解产Rha>碱预水解产Rha>酶预水解产Rha。

It was reported that carbon source in fermentation medium significantly affected the characteristics of rhamnolipids (Rha) produced by Pseudomonas aeruginosa NY3. For this reason, in this paper when discarded animal oil (DAO) was used as fermentation carbon source to study the effect of alkaline prehydrolysis and enzymatic prehydrolysis on the production, structure and performance of Rha, through acid value and hydrolysate of carbon source, component structure and actual application effect of Rha to carry out the study. The results of alkaline prehydrolysis and enzymatic prehydrolysis experiments showed that the acid value of carbon source respectively increased to 72.04 mg/g and 73.75 mg/g from initial 19.81 mg/g, and GC-MS analysis detection results indicated that seven kinds of fatty acids of C14-C18 carbon-chain were released from the carbon source after both alkaline prehydrolysis and enzymatic prehydrolysis, and the yield of Rha increased from 8.28 g/L before prehydrolysis to 15.35 g/L and 17.63 g/L respectively. The analysis results of LC-MS-IT-TOF showed that the proportion of mono-rhamnolipids of Rha produced from non-prehydrolysed DAO, alkaline-prehydrolysed DAO, and enzymatic-prehydrolysed DAO were respectively at 62.07%, 65.67%, 87.32%. It was found under pilot conditions using NY3 strain to treat high concentration of oily sludge from petrochemical enterprise, that Rha could promote NY3 strain to remove petroleum hydrocarbons from oily sludge, and the strength order of promotion effect was Rha of non-prehydrolysed DAO>Rha of alkaline-prehydrolysed DAO>Rha of enzymatic prehydrolysed DAO.