The trypsin inhibitor patterns among thirteen varieties of Japanese soybeans were investigated by gel filtration and isoelectric forcusing. Water extractable protein in Japanese soybeans showed two protein peaks in gel filtration. The first peak did not show any inhibitor activity, but the second peak showed inhibitor activity. 4 to 6 inhibitors were isolated from the inhibitor peaks by isoelectric focusing. The isoelectric points of two major trypsin inhibitors were pH 4.20-4.25 and pH 4.45-4.55, respectively. Based on the difference of the inhibitor content, the 13 varieties of Japanese soybeans were divided into two groups.
It seems that the isolated trypsin inhibitor of pI 3.90-4.00 corresponds to 1.9S inhibitor, of pI 4.20-4.25 to Bowman-Birk inhibitor and of pI 4.45-4.55 to Kunitz inhibitor. The trypsin inhibitor of pI 3.70-3.80 was found in 3 varieties of Japanese soybeans. The pI 4.95-5.05 inhibitor isolated from 12 varieties of Japanese soybeans showed very low content. Trypsin inhibitor of pI 4.70-4.75 was first reported in the paper.

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Action of a cyclodextrin glycosyltransferase in a solution containing starch and sucrose was studied to prepare sucrose-bound syrup. The experimental results indicated as follow.
(1) In the initial stage of the reaction, the enzyme produced cyclodextrin. However, the cyclodextrin disappeared in the final stage. The final product separated by paperchromatography was identified as maltooligosaccharides terminated at the reducing end by sucrose.
(2) The optimum pH range of the reaction was between 5.0 and 6.0, and optimum temperature was 55°C. The best proportion of sucrose to starch was about 1.0.
(3) The syrup showed no reducing activity because it was composed of sucrose-bound maltooligosaccharides and sucrose.

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Antioxidative activities of various dipeptides on linoleic acid were investigated. Nine dipeptides consisting of L-alanine as N-terminal amino acid showed more effective antioxidative activities than those of amino acid mixtures which constitute dipeptides. Especially, Ala-His, Ala-Met, Ala-Ty and Ala-Try prolonged the induction periods to two times longer than those of corres- ponding amino acids.
Among 17 dipeptides consisted of L-tyrosine, L-histidine and L-methionine as N-terminal amino acid, although L-histidine in dipeptides showed less antioxidative activities as compared to those of corresponding amino mixtures, L-tyrosine and L-methionine in dipeptides showed more antioxidative activities than those of amino acid mixtures with exception of Met-Pro and Met-Met.
Antioxidative activity of dipeptide varied with the position of amino acid in peptide. That is, dipeptides consisting of L-tryptophan and L-tyrosine as N-terminal amino acid showed more inhibitive activities on oxidation of linoleic acid than those of dipeptides consisting of respective amino acids as C-terminal. On the contrary, L-methionine and L-histidine in dipeptide as C-terminal amino acid showed stronger antioxidative activities.
Synergistic effect was recognized in combination of dipeptide with d-tocopherol and that effect was similar to that of amino acid.

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Antioxidative activities of soybean protein hydrolyzates by hydrochloric acid and protease (Asp. oryzae origin) were investigated.
In comparison of antioxidative activities among hydrolyzates hydrolyzed from 1 to 30 hr by 6N-HCl at 100°C, the most effective antioxydative activity was recognized in the hydrolyzate for 1 hr and its activity decreased along with the hydrolyzating time. Synergistic effect of hydrolyzate on d-δ-tocopherol was observed and the strongest power was recognized in combination of d-δ-tocopherol and hydrolyzates treated for 3 and 6 hr.
Antioxidative activity of hydrolyzate by protease increased with elapse of time and hydrolyzate for 6 hr (hydrolyzating ratio=15%) showed the most effective activity and its activity decreased along with reaction time.
Hydrolyzates of soybean with 6N-HCl at 100°C for 1 and 30 hr were fractionated by gelfiltration of Sephadex G-25. In comparison of antioxidative activity of each fraction at same O.D. level of ninhydrin reaction, the strongest antioxidative activity was found in peptides with M.W. about 1300. Hydrolyzate by protease for 48 hr was fractionated by the same column. By comparing antioxidative activity of each fraction at same O.D. level at 280nm, the most effective activity was recognized in peptides of M.W. 2500-3000. Synergistic effect of each fraction on d-δ-tocopherol was observed and the most effective activity distributed in peptides with M.W. from 1300 to 2500.

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Conditions for manufacturing of cheese-like product from full fat reconstituted and fresh soybean milk were investigated.
Moisture contents of 3 week's ripened products from reconstituted and fresh milk were 62-67% and 72% respectively. Longer time (2 hours)at lactic fermentation of reconstituted soybean milk induced lower moisture content of finished product.
Residual trypsin inhibitor activity in green soybean curds did not decrease during the ripening. Nitrogen contents in ultrafiltrated fractions (below m.w. 500 and 10, 000) increased during the ripening of product from fresh soybean milk, but trypsin inhibitor activity could not be detected in these fractions.
Calcium contents in above ultrafiltrated fractions of green curd from fresh milk (about 50 ppm.) remarkably decreased during the ripening, and its content in these fractions of 3 week's product was below 5 ppm. This may be the major cause that the proteolysis can not smoothly progress during the ripening.
Slightly browning color change during the ripening was observed on products from reconstituted and fresh full soybean milk.
Product from fresh soybean milk showed more excellent freshness, texture, body and color, though their ripening rate (about 30%) was lower than that of product from reconstituted soybean milk (about 43%).

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Crude tannase preparation which was obtained by ammonium sulfate-precipitation from the mycelial extract of Aspergillus niger AKU 3303 was further purified by a procedure involving acetone precipitation, DEAE-Sephadex column chromatography, Sephadex G-200 gel filtration and SPSephadex column chromatography. The final enzyme preparation showed single band upon a disk electrophoresis.
The properties of the purified tannase were studied with reference to pH-activity relationship, temperature-activity relationship, pH-stability, heat-inactivation and effects of metal ions and other reagents.
It was found that activity of the crude tannase preparation to prevent creaming of tea infusion was slightly higher than that of the purified tannase when infusion was incubated with same units of each enzyme preparation.
Therefore, it was considered that the crude tannase preparation contains certain effective substances on the creaming of tea infusion, but their effects were very small comparing with that of tannase.

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The chemical components of the edible swallow'snest (Enso) was studied. The hot water soluble components of the swallow's nests (S.N), the natural and the refined ones, were separated into cold water-insoluble fractions (R) and cold water-soluble fractions (F). The fractions, R and F were further fractionated by means of the NaI method, and their IR spectra were examined.
1. The average contents of R in the mucilagenous substances were 15.6% for S.N., natural and 66.3% for S.N., refined, respectively.
2. In IR spectra of R and F fractions, anhydrosugar was presumed to occur.
3. The NaI soluble fractions were only 14 to 16% in the R fractions and were dominant in F fractions for all of the samples.
4. In both of the NaI soluble fractions (RS) and the NaI insoluble fractions (RI) in fraction R, absorptions attributed to a sulphate ester were observed.

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Considering the feasibility of commercial scale radiation of sprout inhibition of onions, the dose distribution in onion container was measured at Shihoro potato irradiator. The dose distribution in large container (100×160×130cm) filled with onions was measured with Fricke dosimeter at different distances from cylindrical source which had about 197 KCi of Co-60.
The dose uniformity ratios (Dmax/Dmin) were 2.70, 2.34 and 2.19 at distances of 300, 450 and 550cm from the center of source respectively. From these results, ten thousand tons of onions could be treated in a month at the dose range of 3-6.6 Krad using a same type of irradiator in Shihoro with 174KCi of Co-60 source.

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