Studies on Feeding Stimulants for Jack Mackerel-III. Feeding Stimulant Activity of Nucleotides, Tryptophan, and Their Related Compounds for Jack Mackerel.

Abstract

The feeding stimulant activities of nucleotides-related and tryptophan-related componunds were tested on young jack mackerel Trachurus japonicus at concentrations of 1 and 5 mmol/100g dry diet, respectively. Effective doses of inosine 5'-monophosphate (IMP) and L-tryptophan (Trp) added to the diet on feeding activity were also examined. Of 33 compounds tested, IMP, guanosine 5'-monophosphate (GMP), uridine 5'-mono-phosphate (UMP), UDP, UTP, and Trp were effective. Hipoxanthine, nucleosides (inosine, adenosine, guanosine, uridine), nucleotides including adenosine 5'-monophosphate (AMP), ADP, ATP, IDP, ITP, GDP, GTP, xanthosine 5'-monophosphate, 3'-IMP, 3'-UMP, 2-deoxy-IMP, allyltio-IMP, and Trp-related compounds (D-Trp, DL-Trp, 5-hydroxy-Trp, 5-methyl-DL-Trp, tryptamine, 5-hydroxy-tryptamine, indolepropionic acid, indole-3-pyruvic acid, β-indolelactic acid, indole) were all ineffective. These results suggest that the molecular structure of 6-hydroxy-or 2-amino-6-hydroxy-purine riboside-5-phosphate is required for feeding stimulation toward jack mackerel, and that the activity of Trp was lost by a chemical modification of the molecule. The minimum concentrations of IMP and Trp needed to show the maximum effect were estimated as 0.8 and 5 mmol/100g dry diet, respectively.