Abstrakt: |
Lipases are hydrolytic enzymes which have significant potential for commercial applications, particularly in the breakdown of oil contaminants. Serratia marcescens EGHK-19 isolate exhibited considerable lipase activity. This study investigates the optimization, purification, and characterization of lipase from the Serratia marcescens EGHK-19 isolate. The optimized culture conditions revealed that maximal lipase activity was achieved after 24 hours at 30°C and pH 7, with continuous shaking at 150 rpm. Utilizing a 2% inoculum percentage with 1% diesel and 0.3% tryptone in the presence of Fe2+, Ca2+, Mg2+ salts, and Tween 80 resulted in the highest activity at 17.278 U/ml/min. The purification process involved acetone precipitation and DEAE-Sephadex column chromatography, revealing a molecular weight of approximately 60 kDa on SDS-PAGE. This method exhibited a 0.985-fold purification, and the final yield was limited to 2.097% due to lipase aggregates. Characterization of the purified lipase indicated optimal activity (8.765 U/mL/min) at 40°C a nd p H 7. T he K m a nd V max values w ere c alculated a s 6 .89 m M a nd 6 5.79 µmol/min, respectively. The presence of SDS, Tween 80, and Triton X-100 surfactants resulted in the inhibition of lipase activity. Despite these insuggestss, the biochemical characteristics of the purified lipase suggest its potential as an excellent candidate for various industrial applications. [ABSTRACT FROM AUTHOR] |