NISCAIR Online Periodicals Repository

Research Journals >
Indian Journal of Biochemistry and Biophysics (IJBB) >
IJBB Vol.42 [2005] >
IJBB Vol.42(4) [August 2005] >

Title: Methods for inhibition of residual lipase activity in colorimetric assay: A comparative study
Authors: Kanwar, Shamsher Singh
Kaushal, Rajeev Kumar
Jawed, Arshad
Gupta, Reena
Chimni, Swapandeep Singh
Keywords: Bacillus coagulans MTCC-6375
Microbial and commercial lipases
Ethanol:acetone mixture
Denaturing/reducing/chelating agents
Issue Date: Aug-2005
Publisher: CSIR
IPC CodeC12N1/00; C12N9/00; G01N33/52
Abstract: A comparative study of various treatments for inhibition of the residual activity of a lipase (obtained from Bacillus coagulans MTCC-6375) in a colorimetric assay using p-nitrophenyl palmitate (pNPP) was made. Direct chilling of contents of reaction mixture or addition of chilled mixture of ethanol : acetone (1:1) decreased the residual lipase activity by 94.0 and 95.0% respectively, as compared to lipase incubated at 45oC for 20 min (control). Amongst various ionic and non-ionic detergents, Triton X-100 (0.07%, v/v) and sodium lauryl sarcosine or SLS (0.25%, w/v) partially, and SDS (0.05%, w/v) completely blocked the residual lipase activity of B. coagulans lipase in colorimetric assay. Addition of a serine protease inhibitor, PMSF (15 mM) or EDTA (200 mM) inhibited residual lipase activity by 99.5 and 100%, respectively. However, addition of reducing agents viz., 2-mercaptoethanol and dithiothreitol caused decomposition of chromogenic substrate (pNPP) thus rendering the colorimetric method unfit for lipase assay. EDTA (200 mM) and SDS (0.05%, w/v) were also highly effective in inhibiting the residual activities of lipases of Pseudomonas aeruginosa MTCC-4713, P. cepacia and commercial grade lipolytic preparations such as lipozyme, lipolase and porcine pancreatic lipase. However, PMSF (15 mM) completely inhibited the residual activity of lipase of P. aeruginosa.
Page(s): 233-237
ISSN: 0301-1208
Source:IJBB Vol.42(4) [August 2005]

Files in This Item:

File Description SizeFormat
IJBB 42(4) 233-237.pdf112.68 kBAdobe PDFView/Open
 Current Page Visits: 142 
Recommend this item


Online Submission of Articles |  NISCAIR Website |  National Knowledge Resources Consortium |  Contact us |  Feedback

Disclaimer: NISCAIR assumes no responsibility for the statements and opinions advanced by contributors. The editorial staff in its work of examining papers received for publication is helped, in an honorary capacity, by many distinguished engineers and scientists.

CC License Except where otherwise noted, the Articles on this site are licensed under Creative Commons License: CC Attribution-Noncommercial-No Derivative Works 2.5 India

Copyright © 2015 The Council of Scientific and Industrial Research, New Delhi. All rights reserved.

Powered by DSpace Copyright © 2002-2007 MIT and Hewlett-Packard | Compliant to OAI-PMH V 2.0

Home Page Total Visits: 165406 since 01-Sep-2015  Last updated on 27-Jun-2016Webmaster: