Mobarak-Qamsari E, Kasra-Kermanshahi R, Moosavi-Nejad Z
Department of Biology, Alzahra University, Vanak, Tehran, Iran.
Iran J Microbiol. 2011 Jun;3(2):92-8.
Lipases are particularly important due to the fact that they specifically hydrolyze acyl glycerol, oils and greases, which is of great interest for different industrial applications.
In this study, several lipase-producing bacteria were isolated from wastewater of an oil processing plant. The strain possessing the highest lipase activity was identified both biochemically and sequencing of 16S rRNA gene. Then we increase lipase activity by improving conditions of production medium. Also, lipase from this strain was preliminarily characterized for use in industrial application.
The 16S rRNA sequensing revealed it as a new strain of Pseudomonas aeruginosa and the type strain was KM110. An overall 3-fold enhanced lipase production (0.76 U mL(-1)) was achieved after improving conditions of production medium. The olive oil and peptone was found to be the most suitable substrate for maximum enzyme production. Also the enzyme exhibited maximum lipolytic activity at 45°C where it was also stably maintained. At pH 8.0, the lipase had the highest stability but no activity. It was active over a pH range of 7.0-10.0. The lipase activity was inhibited by Zn(2+) & Cu(2+) (32 and 27%, respectively) at 1mM. The enzyme lost 29% of its initial activity in 1.0% SDS concentration, whereas, Triton X-100, Tween-80 & DMSO did not significantly inhibit lipase activity.
Based on the findings of present study, lipase of P. aeruginosa KM110 is a potential alkaline lipase and a candidate for industrial applications such as detergent, leather and fine chemical industries.
脂肪酶尤为重要，因为它们能特异性水解酰基甘油、油脂，这在不同工业应用中具有重大意义。
本研究从一家石油加工厂的废水中分离出几株产脂肪酶的细菌。通过生化鉴定和16S rRNA基因测序对脂肪酶活性最高的菌株进行了鉴定。然后我们通过改善生产培养基条件来提高脂肪酶活性。此外，对该菌株产生的脂肪酶进行了初步表征以用于工业应用。
16S rRNA测序显示它是铜绿假单胞菌的一个新菌株，模式菌株为KM110。改善生产培养基条件后，脂肪酶产量总体提高了3倍（达到0.76 U mL⁻¹）。发现橄榄油和蛋白胨是产生最大量酶的最合适底物。该酶在45°C时表现出最大脂肪分解活性，且在此温度下活性能稳定维持。在pH 8.0时，脂肪酶稳定性最高但无活性。它在pH 7.0 - 10.0范围内有活性。在1 mM浓度下，Zn²⁺和Cu²⁺分别抑制脂肪酶活性32%和27%。在1.0% SDS浓度下，该酶失去了29%的初始活性，而Triton X - 100、吐温80和二甲基亚砜对脂肪酶活性没有显著抑制作用。
基于本研究结果，铜绿假单胞菌KM110产生的脂肪酶是一种潜在的碱性脂肪酶，是洗涤剂、皮革和精细化工等工业应用的候选酶。
