Direct immobilization of polyphenol oxidases on Celite 545 from ammonium sulphate fractionated proteins of potato (Solanum tuberosum)

In this study an effort has been made to use ammonium sulphate fractionated potato proteins for the direct immobilization of polyphenol oxidase on an adsorbent, Celite 545. The yield of Celite immobilized PPO activity was maximum in the buffer of pH, 7.0 and the support retained 240 units of PPO per gram. The immobilized potato PPO preparation exhibited effectiveness factor 'eta' as 0.71. Immobilized enzyme preparation was significantly more resistant to the denaturation induced by pH, temperature, urea, detergents; SDS, Triton X 100, Tween 20 and water-miscible organic solvents; acetonitrile, dimethyl formamide, dioxane and n-propanol as compared to its soluble counterpart. The activity of soluble and immobilized polyphenol oxidase was remarkably enhanced in the presence of increasing concentration of non-ionic detergents like Triton X 100 and Tween 20. (c) 2006 Elsevier B.V. All rights reserved.