Isolation of Local Lipolytic Isolate from Domestic Compost

Screening of lipolytic bacteria from domestic compost resulting an isolate namely AL17. Morphological analysis shows that the isolates were rod shape and belong to negative gram bacteria. The 16S rRNAs genes of the bacteria have been sequenced, and phylogenetic analysis showed that the isolates were close to genus Pseudoxanthomonas. The enzyme production was synchronized with bacterial growth and reached a maximum level during the late-stationary phase. The optimum pH and temperature of enzyme activity were at pH 9.0 and 60°C.The isolate also showed alcohol tolerance in medium containing 3% and 5% methanol. The ability of bacterial cells to tolerate methanol is an important cell characteristic that determines their use as a biocatalyst in transesterification and other industrial process

Thermostable Lipase from Domestic Compost Isolated Bacteria

Lipase (Triacylglycerol acyl hydrolase), is a hydrolase enzyme that plays an important role in industries such as health, food, biotechnology, and energy. Lipase might be isolated from almost all living organism, either higher organisms or microbes. In this report, lipase was isolated from compost isolated microbe namely AL89 isolate. AL89 was previously identified closed to Pseudoxanthomonas taiwanensis. The crude extract of lipase was produced by incubating of the culture at 55°C for 19 hours. The crude extract was partially purified using acetone fractionation. Fractionation was carried out at concentrations of acetone at 0-20%, 20-40% and 40-60%. The specific activity was determined by hydrolytic activity of lipase with the substrate of para-nitrophenylpalmitate (pNPP). The result showed that the highest activity of the enzyme is 0.0971 U/mg protein from the fraction of 0-20%. Lipase from isolate AL89 showed optimum activity at 55°C and pH 9. In addition the enzyme prefers para-nitrophenyl laurate (pNPL) as substrate. Using zymography analysis showed that the active protein at the size of 70 kDa. All the data suggested the enzyme is thermo and alkali-tolerant lipase