The distribution of polysaccharide hydrolase activity in gastropods and bivalves.

Abstract

Several carbohydrase activities were determined on the crystalline styles and the hepatopancreata from 50 species of shellfish.Laminarinase activity was the highest of other carbohydrase activities in most species. The activity was generally higher in bivalves than in gastropods, especially the crystalline style of certain species such as Gomphina melanaegis, surf clam Mactra chinensis, egg cockle Fulvia mutica have remarkable high activities, reducing sugars produced by those species during 2h at 37°C were 50-70% of the initial substrate weigh. On the contrary, the degradation activities on structural polysaccharides were rather high in small herbivorous gastropods; especially Acmaeidae on alginic acid, Patellidae on xylan, and Littorina brevicula, Batillus cornutus, Patelloida sp. on microcrystalline cellulose, respectively. Although the degradation activity on fucoidan was widely distributed, it was not so strong in most of the species. Degradation activities on the Kombu powder and the Kombu extraction residue were also determined in shellfish, and compared with a commercial cellulase preparations. The activity of chiton Liolophura japonica was close to that of the commercial enzyme on the degradation of the Kombu powder, while sugars produced due to both enzymes were quite different.