title: Stabilization of Chromobacterium viscosum Lipase (CVL) Against Ultrasound Inactivation by the Pretreatment with Polyethylene Glycol (PEG).
abstract: Although ultrasound has been used to accelerate many enzymatic reactions, the low stability of enzymes in such a system still remains a critical issue, limiting its industrial application. Here, we have reported that polyethylene glycol (PEG) pretreatment stabilized Chromobacterium viscosum lipase (CVL) in ultrasound-assisted water-isooctane emulsion. PEGs of different molecular weights and concentrations were used to pretreat CVL, and the pretreated lipase activities for olive oil hydrolysis were investigated at different ultrasonic powers. The best result was attained with PEG400 at 100 mg/ml for a lipase concentration of 0.02 mg/ml and an ultrasonic power of 106 W. The half-life time of PEG400-treated lipase at 106 W was 54 min, a 27-fold higher than that attained using untreated lipase. Circular dichroism (CD) spectra suggested that PEG increased the rigidity of CVL structure, which favored the lipase stability against ultrasound inactivation. These results have important implications for the exploitation of ultrasound in biocatalytic process.
authors.affiliation: Institute of Chemical and Engineering Sciences, Singapore, Singapore. talukder@ices.a-star.edu.sg.|Department of Industrial Biotechnology, Institute of Chemical and Engineering Sciences, 1 Pesek Road, Jurong Island, Singapore, 627833, Singapore. talukder@ices.a-star.edu.sg.
authors.forename: Md Mahabubur Rahman
authors.initials: MM
authors.lastname: Talukder
authors.affiliation: Institute of Chemical and Engineering Sciences, Singapore, Singapore.
authors.forename: Simon Choo Sze
authors.initials: SC
authors.lastname: Shiong
mesh_terms: D004655:Emulsions; D004795:Enzyme Stability; D008049:Lipase / Q000737:chemistry / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000494:pharmacology*; D012997:Solvents / Q000737:chemistry; D000069453:Ultrasonic Waves
chemical_list: D004655:Emulsions; D012997:Solvents; D011092:Polyethylene Glycols; C000595213:polyethylene glycol 400; D008049:Lipase; C454481:lipase, Chromobacterium viscosum
keywords: Biocatalysis; Enzyme inactivation; Lipase stability; Polyethylene glycol; Ultrasound