Post Graduate Department of Chemistry College of Commerce, Patna India

Email:-anilcoc2013@gmail.com

In this article, the spectral characteristics of horseradish peroxidase in aqueous buffer as well as nonionic reverse micelles is reported at various pH values. It is found that the soret band of HRP slightly shifted in acidic as well as in alkaline media with respect to the neutral pH( pH 7.00). The shifting of λmax could be related with the conformational change of the enzyme molecule at different pH values. Further, the absorption spectra of the peroxidase in aqueous buffer as well as in nonionic micellar media at Wo = 15, pH = 7.00, is found virtually unchanged. The molar extinction coefficient (ε) of peroxidase at λ = 403 nm remains more or less constant till pH 11.8 inside the aqueous pool of the reverse micellar system and above this it falls rapidly. The fall of εvalue indicates that there is a change of conformation of the enzyme molecule after pH 11.8