Jornal Europeu de Biologia Experimental Acesso livre

Abstrato

Influence of size on digestive enzyme activities in the Angelwing clam Pholas orientalis

Ruby U. Tizon, Augusto E. Serrano, Jr., Rex Ferdinand M. Traifalgar

This study aimed to elucidate the possible influence of body size in terms of shell size on the activities of digestive enzymes in the crystalline style of the Angelwing clam Pholas orientalis. Sexually mature Angelwing clams were classified into into three group sizes: (1) small (80-100 mm); (2) medium (101-120 mm); and (3) large (>121 mm). α-Amylase, CM-cellulase, agarase, laminarinase, and protease specific activities were measured. α-Amylase and agarase activities were significantly lower in small clams than in medium and large clams which were not significantly different from each other. CM-cellulase specific activity increased almost linearly with size while laminarinase did not have any significant effect on the clams at any size. Small clams exhibited only about a third of the protease activities of that exhibited by either the medium or large clams. The increase in enzymatic activities with animal size was probably due either to increased food requirement for growth, maintenance, or gonad maturation or their combination.