Abstract:
A chemical-defined medium with 0.13% ammonium aulphate as nitrogen source and 2% frutose as carbon source at pH 7.0 and 37 celsius degree were the most suitable culturing condition for the prodution of extracellular lipase by a local strain of Pseudomonas aeruginosa. Glucose was found to repress on the lipase production through catabolite repression. Lipase from P. aeruginosa was partial purified 10.92 fold by using ultrafiltration and Sephadex G-100 gel chromatography. The partial purified enzyme was a complex of subunites with molecular weight of 63,000. The optimum pH and temperature were 6.5 and 35 degree celsius, respectively. The enzyme was able to hydrolyse both long chain fatty acyl ester and short chain fatty acyl ester of glycerol. Enzyme activity was activated by calcium ion but was completely inhibited by Mn[supersciprt 2+] and was partially inhibited by Fe[supersript 2+], EDTA and SDS. The Km for the pirified lipase with olive oil was found to be 4.09 mg./ml. at 37 degree celsius and then assayed at pH 6.0 and 37 degree celsius, the purified enzyme was found to be stable in the pH rang 6.0-7.5. The purified enzyme was stable over 30-40 degree celsius at pH 6.0.