TAILIEUCHUNG - Partial purification and characterization of cellulases from digestive tracts of the African giant snail (Achatina achatina)
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, .
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