Studies on Thiaminase I in Marine Fish-II

Distribution of Thiaminase in Marine Fish

Abstract

Fifty species of marine fish were investigated for the distribution of thiaminase I. and high thiaminase activity was detected in the following 11 species, namely, Konosirus punctatus, Engraulis japonica, Cololabis saira, Hemiramphus sajori, Fistularia petimba, Sardinops melanosticta, Harenguta zunasi, Prognichthys agoo, Spratelloides japonicus, Tylosurus melanotus, and Mugil cephalus.
In the first five of these species thiaminase activity was found in the muscle as well as in the viscera. The other species did not show such activity in the muscle. Generally, thiaminase activity was higher in the viscera than in the muscle. It was particularly high in the spleen of Mugil cephalus, in the kidney of Cololabis saira and Konosirus punctatus, and in the intestine of Hemiramphus sajori.
With seven out of the above 11 species, the optimum pH value for thiaminase ranged from 4.0 to 6.5. However, with some species, it varied by organ even within the same individual fish: the optimum pH value for thiaminase with Mugil cephalus was 5.5 in the spleen but 6.5 in the liver and pyloric caecurn. With Tylosurus melanotus, it was 4.0 in the spleen but 5.5 in the liver.