Studies on the Production of B Vitamins by Intestinal Bacteria of Fish II : Vicissitudes of Thiamine and Riboflavin by Intestinal Bacteria of Carp (Cyprinus Caprio LINNE)

This paper is in the series of our study on vitamin vicissitude by the intestinal bacteria of fish. In the mixed culture of intestinal bacteria of the carp, the existence of certain degree of vicissitude in thiamine and riboflavin contents was observed, which may be attributed to the bacterial activity. Some decrease of riboflavin content in the medium，however, is to be occasioned by the change of conditions, and, in the ordinary states, quite a small amount of riboflavin is expected to be supplied by the activity of the bacteria. Hence the supposed necessity to supplement thiamine and riboflavin, especially the latter, to the carp food. The vicissitude of thiamine and riboflavin is to be affected by pH value in the medium but the affection pattern is different in the two vitamins