A corrected urinary concentration method was presented to simplify the nutritionaljudgment as to vitamins status in human bodies. The standard concentration of vitamins in urine was obtained according to the correspondingcreatinine concentration as the equation (1) as well as Tables 2and 3, whichwere deduced from the urine of 445 seamen and 843 village women;the details of thesame were shown in Table 1. The nutritional judgement is to be made on the basis of the values of standard deviationscalculated from each vitamin. Reliability of this method was examined by comparing the results with concentrationsin blood and with that of saturation method, and it was found that the correlation coefficientbetween blood concentration and corrected urinary concentration was higher thanthat between blood concentration and excretion rate obtained by saturation method. This paper is to report of a nutrition survey about vitamin status of seamen, villagewomen and prisoners by using the above corrected concentration method.
The nature of the proteinase with the optimal pH at 2.8, present in yolk sac, wasinvestigated. The activity was expressed by the absorption of tyrosine at 280 mμ whichwas liberated by the enzymatic hydrolysis of casein. This enzyme action was appreciably activated by cysteine, while it was inhibited byperiodic acid and o-iodosobenzoic acid. The inhibition by these oxidants was completelyreversed by the addition of cysteine. Of metal ions tested, Mg2+, Mn2+, Ca2+, or Zn2+exerted no effect on this proteinase activity, ferrous ion displayed great stimulative influenceupon it, while heavy metals such as Cu2+, Hg2+, and Pb2+ caused powerful inhibitioneven in very low concentration. From these results, it was concluded that this enzyme, together with the proteinase withthe optimal pH at 5.8, of which nature was reported in the preceding paper, was identifiedas a cathepsin type proteinase with-SH group as one of its active centers. It was furtherdemonstrated that the proteinases from yolk sac show the same properties as those fromyolk, suggesting their common origin.
In the previous paper, the author reported that the fish oil, polymerized by heating ina Co2, stream or in air at about 250°C for 10 hours, shows toxicity to rats, that this toxicityis due to the cyclic ethyl ester separated from this oil by the urea-adduct forming method, while the straight chain ethyl ester has a sufficient nutritive value and shows no toxicityat all. In this paper, the experiment on edible rape-seed oil will be reported. This oil, whenpolymerized by heating at 250°C for 50 hours, shows toxicity to rats, and in this case alsothe cyclic ethyl ester, separated by the same method as in the case of the fish oil, showsnoticable toxicity to rats, though somewhat lower than that separated from fish oil. Toomuch heating, therefore, should be avoided even in the case of edible oil.