食品のイノシン酸含量-I

Abstract

Inosinic acid, an alleged tasting substance of foodstuff, was determined by the column chromatographic method using an ion-exchange resin, Dowex 1. The method of R. Bergkvist et al. was adopted and found to be satisfactory for the isolation of inosinic acid from adenine or inosine nucleotides (Fig. 1), but not so sharp in separation of the acid from uridylic acid (Fig. 2). As shown in Fig. 3, however, the separation of nucleoside monophosphates is attained by adopting a longer column and a slightly modified eluting agent. It was also found that the time required for the elution of inosinic acid is reducible without any decrease in accuracy by changing the flow rate and composition of eluting agent, as shown in the footnote of Table 1. The content of inosinic acid determined on the perchloric acid extracts of several kinds of foodstuff is listed in Table 1, together with the results of recovery test on the added inosinic acid. The fish meat reveals higher values, whereas the acid is not detected in the foodstuffs of vegetable origin, dried mushroom and miso (bean paste). Due to the disturbance of unknown substance revealing an intense absorption in ultraviolet region, the determination on sake was impossible.