Inhibition of lipoxygenase by soy isoflavones: evidence of isoflavones as redox inhibitors.

Mahesha, H. G. and Sridevi Annapurna, Singh and Appu Rao, A. G. (2007) Inhibition of lipoxygenase by soy isoflavones: evidence of isoflavones as redox inhibitors. Archives of Biochemistry and Biophysics, 461 (2). pp. 176-85. ISSN 0003-9861

PDF Archives_of_Biochemistry_and_Biophysics_461(2)_2007_176-.pdf Restricted to Registered users only Download (761kB)

Abstract

Hydroperoxides, the products of lipoxygenase mediated pathways, play a major role in the manifestation of chronic inflammatory diseases. Soy isoflavones act as antioxidants due to their ability to scavenge free radicals. Isoflavones inhibit the activity of soy lipoxygenase-1 and 5-lipoxygenase, from human polymorph nuclear lymphocyte in a concentration dependent manner. Spectroscopic and enzyme kinetic measurements have helped to understand the nature and mechanism of inhibition. Genistein is the most effective inhibitor of soy lipoxygenase 1 and 5-lipoxygenase with IC(50) values of 107 and 125 microM, respectively. Genistein and daidzein are noncompetitive inhibitors of soy lipoxygenase 1 with inhibition constants, K(i), of 60 and 80 microM, respectively. Electron paramagnetic resonance and spectroscopic studies confirm that isoflavones reduce active state iron to ferrous state and prevent the activation of the resting enzyme. A model for the inhibition of lipoxygenase by isoflavones is suggested.

Item Type:	Article
Uncontrolled Keywords:	Daidzein; Daidzin; Genistein; Genistin; Lipoxygenase; Inhibition studies; Spectroscopic measurements; Redox inhibitor
Subjects:	600 Technology > 08 Food technology > 22 Legumes-Pulses > 05 Soya bean 500 Natural Sciences and Mathematics > 04 Chemistry and Allied Sciences > 16 Enzyme Chemistry
Divisions:	Protein Chemistry and Technology
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	12 Aug 2008 10:52
Last Modified:	03 Jul 2015 12:22
URI:	http://ir.cftri.res.in/id/eprint/1876

Actions (login required)

View Item