Tween-80和鼠李糖脂对铜绿假单胞菌及枯草芽孢杆菌产蛋白酶的影响

研究了添加表面活性剂Tween-80和生物表面活性剂鼠李糖脂对从堆肥中筛选得到的铜绿假单胞菌和枯草芽孢杆菌生产蛋白酶的影响.用固态发酵的方法,对添加不同浓度的表面活性剂对这2种微生物产蛋白酶能力的影响、2种微生物产蛋白酶能力的差异以及发酵过程中的一些参数(包括菌体数、酶提取液表面张力、pH值和挥发性有机质)进行了考察.结果表明,Tween-80对铜绿假单胞菌和枯草芽孢杆菌产蛋白酶有较大促进作用,添加浓度为0.05%时,能分别使铜绿假单胞菌和枯草芽孢杆菌产蛋白酶最高酶活提高65%和30%;鼠李糖脂对铜绿假单胞菌产蛋白酶有轻微抑制作用,但能将枯草芽孢杆菌产蛋白酶,当添加浓度为0.018%时,鼠李糖脂能将枯草芽孢杆菌产蛋白酶最高酶活提高51%.铜绿假单胞菌产蛋白酶能力明显强于枯草芽孢杆菌,前者对照样的蛋白酶产量是后者对照样蛋白酶产量的6倍多.发酵过程中,铜绿假单胞菌酶提取液的表面张力明显低于枯草芽孢杆菌;添加表面活性剂对菌体生长有一定影响,但对pH值变化影响不大;挥发性有机质变化与微生物酶活成正相关关系.

Effect of Tween-80 and rhamnolipid on the production of protease from Pseudomonas aeruginosa and Bacillus subtilis

Effects of Tween-80 and Rhamnolipid on the production of protease by Pseudomonas aeruginosa and Bacillus subtilis isolated from compost were studied in a solid substrate fermentation(SSF) process. Effects of different concentrations of surfactants on the ability of protease production, the differences of protease production ability between Pseudomonas aeruginosa and Bacillus subtilis and some other parameters, such as bacteria biomass, surface tension of crude enzyme liquid, pH, volatile organic matter were evaluated. The results indicated that Tween-80 at 0.05% significantly increased the production of protease from Pseudomonas aeruginosa and Bacillus subtilis by 65% and 30%. Rhamnolipid at 0.018% could promote Bacillus subtilis to produce protease obviously and the activity of protease was increased by 51%. However, rhamnolipid inhibited the production of protease from Pseudomonas aeruginosa. The yield of enzyme from Pseudomonas aeruginosa was 6 times higher than that from Bacillus subtilis. The surface tension of crude enzyme liquid from Pseudomonas aeruginosa was lower than that from Bacillus subtilis, Surfactants influenced the growth of bacteriums and the cut down of volatile organic matter had a positive correlation with the enzyme activity.