Catalase inhibition an anti cancer property of flavonoids: A kinetic and structural evaluation.

Auteur(s) :
Majumder D., Das A., Saha C.
Date :
Nov, 2017
Source(s) :
International journal of biological macromolecules. #104 p929-935
Adresse :
School of Biotechnology, Maulana Abul Kalam Institute of Technology, BF142, Salt lake, Kolkata 700064, India.

Sommaire de l'article

Flavonoids are dietary polyphenols that present abundantly in fruits and vegetables. Flavonoids have inhibitory effects on enzymes and catalase is one among them. Catalase is a common enzyme ubiquitously found in all living organisms exposed to oxygen. It catalyzes the decomposition of hydrogen peroxide to water and oxygen (2H2O2→2H2O+O2). Inhibition of pure and cellular catalase from K562 cells by flavonoids was similar and exhibited the following efficacy; Myrecetin>Quercetin>Kaempferol and Quercetin>Luteolin>Apigenin demonstrating structure activity relationship. Circular Dichroism (CD) spectra have shown distinct loss in α-helical structure of the catalase on interaction with the flavonoids. All flavonoids inhibited the catalase activity by uncompetitive mechanism. The Km and Vmax values of pure catalase were observed to be 294mM(-1) and 0.222mM(-1)s(-1) respectively and on inhibition with myrecetin the values decreased to a minimum of 23mM(-1) and 0.014mM(-1)s(-1) respectively. Inhibition of catalase will directly results in increased production of Reactive Oxygen Species (ROS) and pro-oxidant property of flavonoids. This inhibition was reversed in presence of Cu(2+) ions because of the chelating affect of flavonoids.

Source : Pubmed