Digestive enzymes along the alimentary tract of the parrotfish Sparisoma cretense

The digestive enzyme profile (total protease, total carbohydrase, alpha-amylase and alpha-glucosidase activity and capacity) along the digestive tract was investigated in vitro at different temperature levels (5, 18, 25 and 37°C) for the only Mediterranean species of parrotfish Sparisoma cretense. Sparisoma cretense (collected from the wild from south-eastern Greece) exhibited very high potential for carbohydrate digestion, as well as relatively increased potential for protein digestion. Total protease activity and capacity was increased especially at neutral and alkaline pH levels and was similar in the anterior and posterior intestine. Total carbohydrase, alpha-amylase and alpha-glucosidase values were quite elevated at 37°C but relatively low at 5, 18 and 25°C. Total carbohydrase and alpha-amylase capacity in the posterior intestine became increasingly important with elevated temperature, while the opposite was apparent for a-glucosidase. These results suggest that, apart from the expected high potential for carbohydrate digestion exhibited, S. cretense also has the elevated capacity for protein digestion, although it lacks a specialized stomach and pyloric caeca. © 2006 The Authors.