Date of Publication: 01-Dec-2014
KINETICS OF OXIDATION OF THIAMINE BY PHOSPHATE RADICAL ANIONS PROTECTION BY CAFFECIC ACID
Author: Biyyala Sreedhar Rao* M. Anand Rao*
Category: Engineering, Science and Mathematics
The oxidation of thymidine by PO4__ampersandsignbull;__ampersandsignminus; has been followed by measuring the absorbance of thymiine at 264 nm to 310 nm spectrophotometrically. The rates and the quantum yields (__ampersandsignphi;) of oxidation of thymine by phosphate radical anion have been determined in the presence of different concentrations of caffeic acid. Increase in [caffeic acid] is found to decrease the rate of oxidation of thymine suggesting that caffeic acid acts as an efficient scavenger of PO4__ampersandsignbull;__ampersandsignminus; and protects thymine from it. Phosphate radical anion competes for thymine as well as for caffeic acid. The quantum yields of photooxidation of thymine have been calculated from the rates of oxidation of thymidine and the light intensity absorbed by Peroxodiphosphate (PDP) at 264 nm, the wavelength at which PDP is activated to sulphate radical anion.
Keywords: Kinetics, thiamine hydrochloride (vit – B1), PDP and caffeic acid.