| Autor: |
El-Ghonemy DH; Department of Microbial Chemistry, Genetic Engineering and Biotechnology Division,
National Research Centre, 33 El Buhouth St., EG-12 622 Giza, Egypt., El-Gamal MS; Botany and Microbiology Department, Faculty of Science, Al-Azhar University, EG-11 884 Nasr City, Egypt., Tantawy AE; Department of Microbial Chemistry, Genetic Engineering and Biotechnology Division,
National Research Centre, 33 El Buhouth St., EG-12 622 Giza, Egypt., Ali TH; Department of Microbial Chemistry, Genetic Engineering and Biotechnology Division,
National Research Centre, 33 El Buhouth St., EG-12 622 Giza, Egypt. |
| Abstrakt: |
Thirty isolated fungal strains were screened for lipase production using Phenol Red plates, containing tributyrin as lipidic substrate, and a novel fungus identified genetically as Curvularia sp. DHE 5 was found as the most prominent strain. Various agro-industrial substrates were evaluated as inert supports for lipase production in solid-state fermentation. The highest yield of lipase ((83.4±2.2) U/g on dry mass basis) was reported with wheat bran medium after seven days of fermentation at pH=7.0, temperature of 30 °C, 70% moisture content, inoculum size of 1.27·10 7 spore/mL and 2% olive oil as an inducer. Supplementation of the medium with 0.05% KCl as an ion source further increased lipase production to (88.9±1.2) U/g on dry mass basis. The enzyme was partially purified through ammonium sulphate fractionation (40%) followed by dialysis, and its optimum pH and temperature were reported at 8.0 and 50 °C, respectively, with remarkable pH and thermal stability. |
