BRD School of Biosciences, Sardar Patel Maidan, Vadtal Road, Satellite Campus, P.O. No. 39, Sardar Patel University, Vallabh Vidyanagar 388 120, Gujarat, India.
Bioresour Technol. 2010 May;101(10):3628-34. doi: 10.1016/j.biortech.2009.12.107. Epub 2010 Jan 21.
A mesophilic bacterium producing a thermostable alkaline lipase was isolated from oil rich soil sample and identified as Acinetobacter sp. EH28. The lipase was partially purified by ammonium sulphate precipitation followed by hydrophobic interaction chromatography with 24.2-fold purification and 57.1U/ml specific activity. The partially purified enzyme exhibited maximum activity at pH 10.0 and at 50 degrees C and was highly stable at 50 degrees C retaining 100% of its activity up to 90min. It was highly stable and retained more than 80% of its initial activity upon exposure to various organic solvents. The EH28 lipase was used for synthesis of the flavor ester ethyl caprylate in organic solvents, thus providing a concept of application of Acinetobacter sp. lipase in non-aqueous catalysis. Reaction parameters best suited for this esterification reaction were 40 degrees C reaction temperature, 1.3:1 ratio of caprylic acid to ethanol and cyclohexane as the medium.
从富含油的土壤样本中分离到一株产嗜温碱性脂肪酶的细菌，并鉴定为不动杆菌属 EH28。脂肪酶通过硫酸铵沉淀进行部分纯化，然后通过疏水相互作用色谱进一步纯化，得到 24.2 倍的纯化倍数和 57.1U/ml 的比活。部分纯化的酶在 pH 10.0 和 50°C 下表现出最大活性，在 50°C 下高度稳定，在 90 分钟内保留 100%的活性。它在各种有机溶剂中非常稳定，在暴露于有机溶剂后保留超过 80%的初始活性。EH28 脂肪酶用于在有机溶剂中合成香味酯辛酸乙酯，从而为不动杆菌属脂肪酶在非水相催化中的应用提供了一个概念。最适合该酯化反应的反应参数为 40°C 的反应温度、辛酸与乙醇的摩尔比为 1.3:1 以及环己烷作为介质。
