Noormohamadi Reyhameh, Tabandeh Fatemeh, Shariati Parvin, Otadi Maryam
Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran ; Department of Chemical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran.
Iran J Microbiol. 2013 Dec;5(4):422-7.
Lipases are valuable biocatalysts which are widely used in the detergent, food, dairy and pharmaceutical industries. The aims of the present study included the isolation of a lipase-producer from industrial zones and the partial characterization of the enzyme.
A number of bacteria were isolated from sites related to the oil industries. An isolate forming a halo zone in a selective medium (TW agar) was then selected and grown on a medium suitable for the production of lipase. The isolate was subsequently identified by the 16S rRNA sequencing method, and its enzyme activity was measured by a spectrophotometer using pNPP as a substrate.
The selected isolate was identified by the molecular method as Pseudomonas sp. Its extracellular lipase activity was 41.5 ± 1.4 U/ml, and the high affinity of this enzyme for the substrate was indicated by the kinetic parameters of Km and Vm, which were estimated by the the Lineweaver-Burk plot as 0.77 mM and 49.5 U/ml, respectively. Activation energy of lipase calculated from the Arrhenius plot was found to be 20.78 kJ/mol, and a temperature coefficient (Q10) of 4.39 indicated the high catalytic activity of the enzyme and the temperature dependence of the enzymatic reaction.
The results demonstrated that the indigenous isolate could have potential applications in many relevant industries.
脂肪酶是有价值的生物催化剂，广泛应用于洗涤剂、食品、乳制品和制药行业。本研究的目的包括从工业区分离脂肪酶产生菌并对该酶进行部分特性鉴定。
从与石油工业相关的地点分离出多种细菌。然后选择在选择性培养基（TW琼脂）中形成晕圈的分离株，并在适合脂肪酶生产的培养基上培养。随后通过16S rRNA测序方法鉴定该分离株，并使用对硝基苯磷酸酯（pNPP）作为底物通过分光光度计测量其酶活性。
通过分子方法鉴定所选分离株为假单胞菌属。其细胞外脂肪酶活性为41.5±1.4 U/ml，通过Lineweaver-Burk图估计的动力学参数Km和Vmax分别为0.77 mM和49.5 U/ml，表明该酶对底物具有高亲和力。根据阿伦尼乌斯图计算的脂肪酶活化能为20.78 kJ/mol，温度系数（Q10）为4.39，表明该酶具有高催化活性以及酶促反应对温度的依赖性。
结果表明该本地分离株在许多相关行业可能具有潜在应用。
