Research Article
Magda C. Semedo, Amin Karma
Abstract
Derivatives of p-tert-butylcalix[4,6,8]arene carboxylic acids were used for selective adsorption of myoglobin. A mixture of myoglobin, laccase and peroxidase was used for extraction with calixarenes and onlymyoglobin was selectively extracted to organic media. Myoglobin and Mb c–calixarene exhibited pseudoactivity of peroxidase in aqueous and organic media. This protein-calixarene complex exhibited the highest specific activity of 1.37 × 10?1 U.mg protein?1 at initial pH 6.5 of myoglobin aqueous solution. Apparent kinetic parameters (V max, K m , k cat and k cat/K m) for the pseudoperoxidase activity were determined in organic media for different initial pH values of myoglobin aqueous solution by Michaelis-Menten plot. The stability of this complex was studied for different initial pH values and t1/2 values were obtained in the range of 3.5–5.2 days. The extracted Mb c in organic media was recovered into fresh aqueous solutions at alkaline pH with a recovery of pseudoperoxidase activity of over 100%.