title: Glutaraldehyde activation of polymer Nylon-6 for lipase immobilization: enzyme characteristics and stability.
abstract: An extracellular alkaline lipase of a thermo tolerant Bacillus coagulans BTS-3 was immobilized onto glutaraldehyde activated Nylon-6 by covalent binding. Under optimum conditions, the immobilization yielded a protein loading of 228 microg/g of Nylon-6. Immobilized enzyme showed maximum activity at a temperature of 55 degrees C and pH 7.5. The enzyme was stable between pH 7.5-9.5. It retained 88% of its original activity at 55 degrees C for 2h and also retained 85% of its original activity after eight cycles of hydrolysis of p-NPP. Kinetic parameters Km and Vmax were found to be 4mM and 10 micromol/min/ml, respectively. The influence of organic solvents on the catalytic activity of immobilized enzyme was also evaluated. The bound lipase showed enhanced activity when exposed to n-heptane. The substrate specificity of immobilized enzyme revealed more efficient hydrolysis of higher carbon length (C-16) ester than other ones.
authors.affiliation: Department of Biotechnology, Himachal Pradesh University, Summer Hill, Shimla 171005, HP, India.
authors.forename: Shweta
authors.initials: S
authors.lastname: Pahujani
authors.forename: Shamsher S
authors.initials: SS
authors.lastname: Kanwar
authors.forename: Ghanshyam
authors.initials: G
authors.lastname: Chauhan
authors.forename: Reena
authors.initials: R
authors.lastname: Gupta
mesh_terms: D002209:Caprolactam / Q000031:analogs & derivatives* / Q000737:chemistry; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000378:metabolism*; D005976:Glutaral / Q000494:pharmacology*; D006868:Hydrolysis; D007700:Kinetics; D008049:Lipase / Q000378:metabolism*; D011108:Polymers / Q000737:chemistry*; D013379:Substrate Specificity
chemical_list: D004800:Enzymes, Immobilized; D011108:Polymers; C009916:nylon 6; D002209:Caprolactam; D008049:Lipase; D005976:Glutaral