Conversion ratio of tryptophan to niacin in rats fed with a nicotinic acid-free, tryptophan-limiting diet.
The effects of amino acid composition on the conversion ratio of Trp to niacin in rats were investigated. The ratio in the group fed with a nicotinic acid-free, 9% casein-sucrose diet (basal diet) was 3.5%. This ratio was statistically decreased to 0.2% by the addition of 2% glycine, 0.078% L-threonine, and 0.2% L-cystine, and restored to 3.2% by the further addition of 0.1% tryptophan. From these results and our previous findings, it was considered that Trp imbalance might be a manifestation of niacin deficiency.
Shibata
K
K
Department of Human Health Seince, Faculty of Human Sciences, Osaka International University for Women, Japan.
D000818:Animals; D004032:Diet; D008297:Male; D009525:Niacin / Q000172:deficiency / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D014364:Tryptophan / Q000378:metabolism*
D009525:Niacin; D014364:Tryptophan