Roasted sesame oil has many different kinds of lignans such as sesamin, sesamolin, and sesamol, so sesame oils have very high oxidative stability. However, there are few methods for evaluating the oxidative stability and other qualities. The purpose of this study is to estimate the quality of roasted sesame oil using ultra-weak photon emission. In this report, we investigated how roasting sesame seeds influenced the ultra-weak photon emission from its extracted oils. We also investigated how the ultra-weak photon emission was influenced by the quality change in accelerated degradation tests (120°C and 20l/h aeration) and long-storage tests. The results were as follows. The sesame oil became dark and the amounts of sesamol increased when roasting temperature was raised. Ultra-weak photon emission from the sesame oils also became higher at higher roasting temperatures. Accelerated degradation test revealed, through ultra-weak photon emission measurement and quality analysis, that there were three chemical reaction phases during degradation of the sesame oil. First, the balance between the hydroperoxide production rate from oils and the hydroperoxide decomposition rate was unstable. Second, the balance became stable. Finally, the hydroperoxide production rate became very high. The photon emission from sesame oils decreased when the quality became poor in the second reaction phase. The photon emission decrease with quality degradation was a characteristic emission phenomenon for roasted sesame oils. And we also clarified that sesamol addition in the sesame oil was caused higher photon emission. These results demonstrated the possibility of quality evaluation of roasted sesame oil using ultra-weak photon emissions.

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This study was designed to isolate and analyze inhibitory peptides against angiotensin I-converting enzyme (ACE) from protease treated Royal Jelly (RJ) hydrolysate. We obtained the fractions which inhibited ACE from the RJ hydrolysate treated with protease N using octadecyl silica gel (ODS) and Superdex^TM-peptide 10/30 (GPC) colums. In ODS column chromatography, an ACE inhibitory fraction was recovered after elution with 10% ethanol in water. And from it the most active fraction was obtained through 3 step high performance liquid chromatographies. As a result, two different ACE inhibitory peptides were purified. On the other hand, the RJ hydrolysate was fractionated with Superdex^TM-peptide 10/30 GPC column chromatography to obtain di- and tri-peptide fractions which processed marked inhibitory activity against ACE. And we carried out another 2 or 3 step HPLC of the fraction, obtaining 4 different peptides. By analysis of these 6 peptides using an amino acid sequencer, we could obtain Ile-Tyr (IY), Val-Tyr (VY), Ile-Val-Tyr (IVY), Tyr-Tyr (YY), Ile-Phe (IF), and Lys-Ser (LS); IC₅₀ values for ACE inhibition were 0.008, 0.02, 0.018, 0.028, 0.034, and 1.55mg/ml, respectively. Especially, IY, YY, and LS were isolated first time from the RJ. In conclusion, this study elucidated that novel ACE inhibitory peptides were contained in RJ hydrolysate, and these might play an important role in ability of the RJ hydrolysate to depress the blood pressure via ACE inhibition.

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γ-Aminobutyric acid (Gaba) and free amino acids contents of germinated rice products were determined. A correlation between free amino acid contents and Gaba contents of unpolished rice, germinated unpolished and germinated unhulled rice products was found (r=0.928). It was proved that the Gaba contents of germinated rice products of Akitakomachi was higher than those of the germinated rice products of Milkyqueen. After heating at 50°C or 60°C for 1 hour, the free alanine content of the germinated unhulled rice products increased, paralleled with decreasing of the free glutamic acid content.

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A new method was developed to investigate histological structures of cooked rice kernels. A single kernel of rice was infiltrated with 100% ethanol by carrying the kernel through a graded series of ethanol-water mixtures. The rice kernel was then embedded in paraffin and sectioned on a standard microtome. During the sectioning process, a special adhesive tape was used to collect the sections and place them onto slides so that they remained flat and were observable by microscope. The quality of sections was shown using scanning electron microscope. The use of the adhesive tape technique combined with autofluorescence characteristics of phenolic compounds located in cell walls in the UV range allowed cell formations to be visualized throughout an entire longitudinal section of a rice kernel. Cell wall disruptions in the sections of the cooked rice kernel were also visualized. This technique shows potential for studying histological characteristics of cooked rice kernels.

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We examined "Sarara" (Capsicum annuum L. cv. Sarara) which is a new kind of sweet pepper and discussed the change of the carotenoid composition in its mature process. The following results were obtained. (1) β-Carotene existed in all of the sweet peppers which were taken between 2 and 10 weeks after flowering. (2) The sweet peppers taken between 2 and 6 weeks after flowering contained β-carotene and lutein. The content decreased gradually. (3) In the sweet pepper of the seventh week after flowering all lutein was lost. The quantity of zeaxanthin and capsanthin rapidly increased. It increased until the ninth week and began to decrease in the tenth week. The quantity of capsanthin in the ninth week after flowering was 19000μg/100g, which was 60% of the content of total carotenoid. (4) When both capsanthin and β-carotene existed in "Sarara", capsanthin and β-carotene were contained with the fixed rate: 1:10.

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An alkaline protease inhibitor (API) from Aspergillus oryzae W-1 was purified to homogeneity by DEAE-Cellulose and Hydroxyl apatite column chromatographies. The molecular mass of the inhibitor was estimated to be 14KDa by SDS-PAGE and 12.5KDa by gel filtration on Sephadex G-50 column chromatography; the isoelectric point was 4.6. API was extremely heat stable and retained 100% of its original activity even after heating in a boiling water bath for 5min in the pH range of 4-6. API exhibited an inhibitory activity against the proteolytic activity of alkaline protease from A. oryzae or A. oryzae W-1, but not for subtilisin, subtilisin BPN', papain, ficin, bromelain, trypsin and α-chymotrypsin. It was found that the inhibitor was inactivated by the action of the latter seven enzymes.

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