Production of extracellular lipase by Enterococcus faecium E68 with olive oil waste as substrate

With green technologies, the damages caused by agro-technological wastes to the environment are eliminated. In our study, it was aimed both to prevent the harm of olive oil waste to the environment and to produce lipase enzyme, which is an important biotechnological product.. E. faecium E68 obtained from milk and dairy products was used in the production of lipase enzyme. E. faecium E68 was developed in lipase production medium containing 10% olive waste, pH6.5, at 37oC with 120 rpm agitation for 48 hours. The effect of temperature, pH metal ion, surfactant and NaCl was also determined. The molecular weight of the partially purified extracellular lipase enzyme was estimated to be around 19-20 kDa  by SDS-PAGE.   The optimum temperature was 45°C, while the enzyme exhibited appreciable thermostability retaining of activity at 55°C for 48h. The lipase was most active in the pH range of 3-11 with an optimum activity at pH 10. 1mM, Ca 2+, Mn2+, Cu2+, Ni2+, Zn2+, Mg2+ and K+ ions modulated the activity of the enzyme but inhibited by Hg2+, SDS and Triton X-100. The enzyme is halophilic and 25% NaCl salt increased the activity. Olive oil waste may be the preferred substrate for lipase production.