title: Lipase production from a novel thermo-tolerant and extreme acidophile Bacillus pumilus using palm oil as the substrate and treatment of palm oil-containing wastewater.
abstract: The thermo-tolerant and extreme acidophilic microorganism Bacillus pumilus was isolated from the soil collected from a commercial edible-oil extraction industry. Optimisation of conditions for the lipase production was conducted using response surface methodology. The optimum conditions for obtaining the maximum activity (1,100 U/mL) of extremely acidic thermostable lipase were fermentation time, 96 h; pH, 1; temperature, 50 °C; and concentration of palm oil, 50 g/L. After purification, a 7.1-fold purity of lipase with specific activity of 5,173 U/mg protein was obtained. The molecular weight of the thermo-tolerant acidophilic lipase (TAL) was 55 kDa. The predominant amino acid in the TAL was glycine. The functional groups of lipase were determined by Fourier transform infrared spectroscopy. TAL exhibited enhanced activity (114 %) with dimethyl sulphoxide (20 %, v/v), and it showed a moderate activity with methanol, hexane and benzene. The optimum conditions for the treatment of palm oil in wastewater using the TAL were found to be time, 3 h; pH, 1; temperature, 50 °C with pseudo second-order kinetic constant of 1.88 × 10(-3) L mol(-1) min(-1). The Michaelis-Menten enzyme kinetic model and the nonlinear kinetic model were evaluated for the TAL. TAL established hydrolysis efficiency of 96 % for palm oil in wastewater at 50 °C.
authors.affiliation: Environmental Technology Division, Council of Scientific and Industrial Research (CSIR)-Central Leather Research Institute (CLRI), Adyar, Chennai, 600 020, Tamil Nadu, India.
authors.forename: P
authors.initials: P
authors.lastname: Saranya
authors.forename: H
authors.initials: H
authors.lastname: Sukanya Kumari
authors.forename: B
authors.initials: B
authors.lastname: Prasad Rao
authors.forename: G
authors.initials: G
authors.lastname: Sekaran
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001407:Bacillus / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001426:Bacterial Proteins; D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008049:Lipase / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D000073878:Palm Oil; D010938:Plant Oils / Q000378:metabolism*; D013696:Temperature; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D008049:Lipase; D000073878:Palm Oil; D010938:Plant Oils; D062065:Wastewater; D014874:Water Pollutants, Chemical; C428386:thermostable lipase