Lipase Production by Fungal Isolates Grown inPalm Oil Mill Effluent

摘要

Aims: The present work is aimed at determining the optimum conditions of pH, temperature and nitrogen concentration for lipase production by Candida rugosa and Geotrichum candidum in POME. Place and Duration of Study: This work was carried out at the Department of Microbiology, Michael Okpara University, Umudike-Abia state, Nigeria from July to December, 2013. The organisms used in the study were isolated in a previous work by the authors. Methodology: Five milliliter of sterile water was added to respective agar slant containing the two different fungal isolates while developed growth was scrapped with sterile needle and subsequently transferred into nutrient broth contained in 250 mL Erlenmeyer flasks. These flasks were further incubated for 48 h at 28o C on rotary shaker at 180rmp. At this stage 0.1 mL of inoculum was transferred to the production medium (POME) and incubated for 144 h.Results: At initial pH6.0, C. rugosa produce maximum lipase activity of 26.37 UmL-1 while G. candidum showed highest activity of 29.4 UmL-1 at pH 7. C. rugosa alo showed maximum lipase activity of 27.8 UmL-1 at 30oC while G. candidum produced highest lipase activity (24.9 UmL-1) at 35oC. The use of soybean meal in the optimization of production lipase revealed that at concentration of 3.5%w/v, the respective fungi isolates were best supported for lipase yield with maximum activity of 25.97 UmL-1 by C. rugosa and 28.32 UmL-1 by G. candidum.Conclusion: This work evaluated the effect of three culture conditions (pH, temperature and nitrogen conc.) on lipase production by G. candidum and C. rugosa cultivated in POME. Results reveal that the factors were critical to growth and lipase production by the organisms and may be useful indices in the production of lipase even from other oil processing effluents.