Universal Journal of Microbiology Research 7(1): 1-6, 2019 http://www.hrpub.org DOI: 10.13189/ujmr.2019.070101 Production and Characterization of Lipase Enzyme Expressed by Crude Oil Contaminated Soil Isolates Ndubuisi Gabriel Elemuo 1 , Sunday Sunday Ikiensikimama 2 , Chikwendu Ebenezer Ubani 2 , Evans Chidi Egwim 3 , Justice Obinna Osuoha 1,* 1 World Bank Africa Center of Excellence in Oilfield Chemicals Research, University of Port Harcourt, Nigeria 2 Department of Petroleum and Gas Engineering, University of Port Harcourt, Nigeria 3 Department of Biochemistry, Federal University of Technology, Minna, Nigeria Copyright©2019 by authors, all rights reserved. Authors agree that this article remains permanently open access under the terms of the Creative Commons Attribution License 4.0 International License Abstract Lipases are hydrolytic enzymes responsible for the hydrolysis of triacylglycerol into glycerol and free fatty acids. The biodiversity of crude oil contaminated soil was explored for the isolation of novel potent lipase producing microorganisms. In this current study, microorganisms isolated from crude oil contaminated soils were screened for lipase activity and expression. Six fungal strains namely: Yeast, Aspergillus flavus, Aspergillus niger, Verticillus sp., Penicillum sp., and Microsporum audouini demonstrated lipase producing potentials and the best two: Verticillus sp. and Penicillum sp. were selected for enzyme production and characterization. The lipase enzyme was produced in broth medium. Optimization of selected biochemical parameters reveal that optimum temperature for lipase activity was 40 ºC, pH 7 with an incubation time of 168 h for lipase expressed by Verticillus sp. and 40 ºC, pH 8 with an incubation time of 144 h was established for lipase expressed by Penicillium sp. The kinetic parameters of the lipase enzyme revealed that the enzymes had low Km (0.19 and 0.30 respectively) for the selected substrate. Keywords Lipase, Lipase Production, Kinetic Parameters, Optimum PH and Temperature 1. Introduction Lipases, classified as EC 3.1.1.3 are enzymes that catalyze the complete breakdown of oils and fats by converting them into glycerol and fatty acids (Jaiswal et al., 2017). The principal substrate for lipase enzymes are triacylglycerols. The capacity of lipase to carry out numerous chemical biotransformation is the basis for their increasing popularity in the chemical, detergent, pharmaceutical, food and oil industries. In this regard, they are extensively utilized for lipolysis of cream and fat, ripening of cheese, for the enzymatic hydrolysis of milk and for the enhancement of flavor etc. in the diary and food industries (Franken et al., 2009). Lipases are also utilized to augment the absorbency of fabrics in the textile industry, as additives for the production of washing powder in the detergent industries, for diverse transesterification reactions and production of polymers that are biodegradable (Hasan et al., 2006; Jaiswal et al., 2017). In the oil and gas industry, the use of enzymes has been recently suggested for several applications. A robust of enzymes has been provided for tolerating oil reservoir condition by the modern biotechnology industry. Some applications of enzymes in the oil and gas company were reported by Harris and Mckay (1998). Such application includes; breaking of gel in drilling operation to avoid filter cake formation, removal of Sulphur in hydrocarbon, production of “enzyme-based acid” which is used for the purpose of treating formation damage and matrix-acidizing of carbonate, pre-treatment of biopolymers using enzyme to improve the handling characteristics of biopolymer. Furthermore, lipases have also been employed as catalyst for enhanced production of diverse products utilized in paper, pulp and cosmetic industry (Jaiswal et al., 2017). Many thermostable bacterial lipases have been isolated and characterized (Kumar et al., 2005) from different ecological zones. Among the identified bacteria, Pseudomonas sp., Chromobacterium sp., Achromobacter sp., Serratia sp. and Alcaligenes sp. have been evaluated for possible production of lipases (Jaiswal et al., 2017). As a matter of fact, microorganisms that has the capacity to express lipase can be isolated from numerous habitats which include: crude oil contaminated soils, deteriorated food, diary product industries and wastes from vegetable oil industries to mention but a few (Sharma et al., 2001). According to Koet et al. (2005), soils entertain diverse microorganisms that could be potent producers of lipase and other enzymes of industrial value. The screening of novel microorganisms isolated from distinct ecological