[in Japanese]

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The present study was undertaken to examine the protecting factor for L-ascorbic acid oxidation in bracken.
Fully matured bracken has little protective effect on L-ascorbic acid oxidation. The protective effect of purified product from bracken varied with the quantity of Cu ion and the pH of the reaction mixture. To examine the effective component, the crude product was fractionated and the purine fraction was found to have a protective effect on L-ascorbic acid oxidation. The purified effective component was further analyzed by electrophoresis and mass spectroscopy. The results indicated that the effective component was a purine derivative containing adenine. The protective effect of hydrolysate of the crude component was compared with authentic nucleic acid-related substances which have been recognized as protectors. The crude hydrolysate had little effect at low concentration compared with the purine fraction.

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Sterol composition of serum lipoprotein fractions that were separated by ultracentrifugation were determined in several experimental animals including man.
The observation that only quite a low level of phytosterols occurred in serum from healthy men who had been received oral phytosterols suggested the least absorptive ability of man among the animals examined. Approximately 50% of serum phytosterols was carried in low density lipoproteins and 35% in high density lipoproteins (HDL). Young male chicks, but not laying hens, appeared to absorb a conspicuous portion of dietary phytosterols. The concentration of egg yolk cholesterol decreased by about 10% after feeding plant sterols. Also there was an increase in yolk phytosterols, though the absolute quantity was very low. Serum from horses fed formula feed contained only low percentage of phytosterol, but due to their extraordinarily high serum cholesterol levels, it was estimated that quantitatively considerable amounts of phytosterols were circulating, mainly in HDL. Serum from cattle and swine, that were fed formula feed, contained small proportions of phytosterols, but in very-low density lipoproteins from cattle the percentage of the sterols was definitely higher than any other species examined. Rabbit appeared to absorb plant sterols at a relatively high rate and this may be a phenomenon common to the rodent as demonstrated previously in rats.
The distribution of plant sterols and the ratio of campesterol: β-sitosterol in each lipoprotein differed as animals differed. The data are of suggestive that not only the extent of absorption of phytosterols, but the metabolism differ specifically from one animal to others.

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The determination of L-ascorbic acid (AsA) is usually performed by the indophenol method or by the dinitrophenylphydrazine method, but the contaminations of some compounds having the similar redox potential as this of AsA-dehydroascorbic acid (DHA) system and also of some carbonyl compounds such as sugars or so on were recognized to disturb this determination. The determination of diketo-gulonic acid (DKG), one kind of oxidized products of AsA, is also the troublesome one. These are the shortages of these methods.
Then, for the determination of AsA, DHA and DKG, the isotachoelectrophoretic method is applied. As the leading solution, 0.01N β-alanine solution (pH 3.6), and as the terminal solution, 0.01N ncaproic acid are selected. Potential unit values (PU values) of AsA and DKG are confirmed to be 0.63±0.02 and 0.28±0.02, respectively. Nevertheless, as DHA has the small mobility against this terminal solution and also others tested, this compound moved together with the terminal solution and PU value of DHA could not be obtained. The reason why DHA having so small mobility was also discussed.

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As reported in our previous paper, L-ascorbic acid (AsA) could be determined by the isotachoelec-trophoretic method. Then the application of this method to the determination of this vitamin in foods was undertaken, and the utility of this method was checked.
It was found that, when metaphosphoric acid was employed as the extraction medium, it took so long time before the appearance of AsA peak on the electrophoretic chart, and contrary to this phenomenon, the extract with 0.01 N-HCl containing 2% thiourea was found to require not so long electro-phoretic period, and the recovery ratio of AsA added to foods was found to be satisfactory. Then this medium was judged to be the best one for the extraction of AsA from foods.
When β-alanine-HCl solution was employed as leading solution, the extract containing AsA and L-glutamic acid moved as the mixed zone during the electrophoretic procedure, and by this, the deter-mination of AsA became impossible, but this mixed zone was found to separate each other with α-naphthylamine leading solution. Even when the β-alanine-HCl leading solution was employed, the determination of AsA was found to be possible by the combined use of the potential gradient detector and the ultraviolet adsorption detector, the former detector was used for the identification of AsA and the latter for the determination of this compound. For the separation of AsA and D-araboascorbic acid, the successful results were not obtained, even though the combination of these two detectors.

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Comparisons of several enzymatic methods, colorimetric methods and the gas chromatographic method for the determination of cholesterol were undertaken.
Three kinds of enzymatic method consisting of the respective cholesterol oxidase (EC 1. 1. 3. 6) isolated from microorganisms (Nocardia erythropolis and Brevibacterium sterolium) or fungus (Schizophyllum commune) were applied to the assay of serum cholesterol. In the obtained data among these enzyme methods, there was no difference dependent on the variation of origin of enzyme. Substrate specificity of these enzymes was also investigated by comparing relative intensity of coloration to authentic cholesterol or analogues. Enzymatic responses of these methods to authentic sitosterol or stigmasterol were estimated as about 60-70% of that to cholesterol.
In the enzymatic method, concomitant presence of neutral sterols with cholesterol in foods also disturbed the determination of true cholesterol concentration.
A enzymatic and two colorimetric (Liebermann-Burchard and Kiliani) methods was compared to make clear the specificity for sterols (lanosterol, campesterol, sitosterol, stigmasterol, fucosterol, desmosterol and coprosterol). The enzymatic method gave lower values to various sterols measured as cholesterol than the above colorimetric methods.
The gas chromatographic procedure was the most suitable method for the determination of net cholesterol concentration in foods containing several neutral sterols.

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Effects of different dietary proteins on plasma and liver lipids were examined in rats fed diets containing the isonitrogenous level (3.2%) of either casein, whole egg protein, soy bean protein, wheat gluten or rice protein. The concentration of plasma cholesterol was lower in rats fed soy protein or egg protein than in the animals fed casein, the difference was statistically significant in one experiment. The increase in liver cholesterol due to feeding a high cholesterol (1.0%) diet was most marked with casein and the least with egg protein. The dietary protein-dependent responses of plasma and liver lipids may at least be a consequence of the differences in the composition and/or the relative concentration of specific amino acids.

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Alkali soluble proteins were obtained from two edible brown algae, Heterochordaria abietina and Laminaria japonica, containing nitrogen of 11.7% and 10.4%, respectively. Eighteen common amino acids were determined in the two proteins. The proteins isolated from both algae contained essential amino acids in higher levels, where E/T ratios were 2, 779 in Heterochordaria abietina and 2, 989 in Laminaria japonica. They were higher than that of the provisional ratio of FAO/WHO (1973). As compared to the provisional amino acid pattern (FAO/WHO in 1973), the amino acid scores of both proteins were determined as 95 and 73, respectively, and tryptophan was a first limiting amino acid. It is interested that the amino acid scores of both proteins were higher than that in higher plants, being alike rather to animal proteins.
In vitro digestibility, both proteins were lower in pepsin and higher in pancreatin and highest in pronase. The protein from Heterochordaria abietina was found slightly low digestibility than that of milk casein, but more easily digested than that of Laminaria japonica.

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Amino acids of vegetable foods containing high amount of carbohydrate were analyzed as follows:
Vegetable foods were dissolved or suspended in formic acid by heating and crushing in a Potter homogenizer. A portion of the solution containing 2 to 5mg of protein was transferred to hydrolysis tubes and dried over solid caustic soda in a desiccator at reduced pressure. Acid hydrolysis was carried out in 8ml of 6N hydrochloric acid containing 1% thioglycolic acid at a reduced pressure of 10^-1mmHg and by heating at 115°C for 20 hours. Cystine and cysteine were analyzed as cysteic acid in acid hydrolyzates after performic acid oxidation by Moore's method. Tryptophan and tyrosine were estimated after hydrolysis in 5N sodium hydroxide at 135°C for 24 hours and reduced pressure. The amino acids were assayed on an autoanalyzer Hitachi KLA-5 with 6mm column and by a two column system.
The above procedure did not show sufficiently high recoveries of amino acids, but the results obtained showed estimated data of some amino acids, arginine, cystine, methionine and tyrosine were usually higher than the reference data. This means the necessity of new analyses of vegetable foods.

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It is empirically found that the cooked egg-white by microwave becomes rubber- or sponge-like. The coagulated egg-white was hydrolyzed by protease (DIFCO trypsin, activity 1: 250) at pH 7.6 at 35°C. The degree of the hydrolysis of the egg-white cooked by electronic range at 600W for 10 to 30 seconds was decreased than that of the egg-white cooked by steamer for 2 to 20 minutes. The power of the microwave (180 to 600W) for cooking was no effect on the in vitro digestability of protein with protease.

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The present paper was undertaken to examine the contents of sodium, calcium, potassium, iron and phosphorus and the forms of sodium and potassium in muscle of Mutugoro (Boleophthalmus pectinirostris) and Warasubo (Odontamblyops rubicundus) in the Ariake Bay. The results may be summarized as follows:
The contents of Na, K, Ca, Fe and P in Mutugoro muscle were ranged 86-140, 300-330, 28-31, 3.7-4.0 and 120-124mg%. And the ranges of 103-140, 330-345, 56-69, 5.1-5.6 and 148-156mg% were found in Warasubo muscle respectively.
These minerals concentration in Mutugoro and Warasubo eggs was found 70, 72; 210, 200; 29, 27; 2.0, 1.4 and 15, 12mg%.
The relation of the concentration between these minerals was found K>P>Na>Ca>Fe in muscle. And its were found K>Na>Ca>P>Fe in eggs.
And then the authors distinguished free forms of sodium and potassium from bound forms in muscle homogenate by 10% trichloroacetic acid treatment.
The ratios of free Na and K of the extracted solution in Mutugoro and Warasubo muscle by water were within the ranges of 52-54.9%, 73-73.1% and 62-63%, 79-80.8%.
The relation of Na, K was maintained in free forms as well.

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