ビタミンCの安定化に関する研究(5)-ビタミンC溶液の安定化(3)-

概要

論文の詳細を見る
In the previous paper of this series, it was found that thiourea, thioglycolic acid and reducetic acid were the effective antioxydants in the aq. soln. of l-ascorbic acid among 17 tested reagents. And it was also reported that the solution of reductic acid itself changed the colour of an indophenol soln. and so its stabilizing efficiency must be determined by feeding experiments with animals. First, in this paper it has been ascertained that reductic acid has no efficiency to preserve l-ascorbic acid by animal feeding experiments and the colour change of the indophenol soln. is due to the remaining reductic acid, and not to ascorbic acid. Next, the derivatives of thiourea S-methyl-iso-thiourea (I), N-methyl-thiourea (II), N-phenyl-thiourea (III), N, N-diphenyl-thiourea (IV), tetraphenyl-thiourea (V), and rubianic acid (VI)_??_ were synthesized and tested for their efficiency to prevent the auto-oxydation of an ascorbic acid soln. The result was as follows. VI and V rather accelerated the oxidationthan the control containing only ascorbic acid; hydroquinone and I had similar effects and 80% of ascorbic acid was destroyed after 12 days; IV, 111. and thiourea were effective and among these 3 compounds thiourea was best, for example about 70% of ascorbic acid remained during 14 days under experimented conditions at 37°
社団法人日本農芸化学会の論文