Crude cellulase was extracted from the digestive tracts of 30 mature Achatina achatina and subjected to a 3-step purification process of ammonium sulfate precipitation, dialysis, and gel filtration. | Turkish Journal of Biology Research Article Turk J Biol (2013) 37: 199-205 © TÜBİTAK doi: Partial purification and characterization of cellulases from digestive tracts of the African giant snail (Achatina achatina) Paul Chijioke OZIOKO, Sabinus Oscar Onyebuchi EZE*, Ferdinand Chiemeka CHILAKA Department of Biochemistry, University of Nigeria, Nsukka, Enugu State, Nigeria Received: Accepted: Published Online: Printed: Abstract: Crude cellulase was extracted from the digestive tracts of 30 mature Achatina achatina and subjected to a 3-step purification process of ammonium sulfate precipitation, dialysis, and gel filtration. This purification procedure gave 3 prominent enzyme activity peaks that coincided with protein peaks and were designated A, B, and C, corresponding to high endoglucanase, β-glucosidase, and total cellulase activities, respectively. Temperature optima of 50 °C were recorded for β-glucosidase and total cellulase while 45 °C was recorded for endoglucanase. Total cellulase, glucosidase, and endoglucanase showed maximum activities at pH values of , , and , respectively. Kinetic studies show that total cellulase has a Vmax and Km of µmol/min and mg cellulose and endoglucanase has values of µmol/min and mg Na-CMC, while the values of β-glucosidase are µmol/min and mM cellobiose, respectively. This study shows that cellulases from digestive tracts of A. achatina could be utilized for degradation of cellulose-containing materials because of their high thermostability and acid/alkali stability, which reflect the potential commercial significance of the enzyme. Key words: Achatina achatina, cellulases, purifications, characterization, sodium carboxymethyl cellulose (Na-CMC), cellobiose 1. Introduction Cellulase (EC ) refers to a class of hydrolase enzymes produced by fungi, bacteria, protozoans, .
