Antimicrobial peptides, α and β-thionins, were extracted from barley and wheat flour with 0.075-0.15N HCl. The degradation of α and β-thionins by digestive enzymes at 37°C was examined in vitro. No degradation of α-thionin was observed after the incubation of 10μg of barley α-thionin with 1μg of pepsin A for 16hr. Similar resuls were shown for wheat α-thionin and barley β-thionin. Denaturated wheat α-thionin by S-pyridylethyl modification of cystine residues was degraded by pepsin. Trypsin (0.5μg) and chymotrypsin (5μg) degraded 9.1μg and 7.2μg of wheat α-thionin for 1hr, and produced some partially hydrolyzed peptides. Similar results were obtained for barley α and β-thionins. The partially hydrolyzed peptides had no more antibacterial activity. The partially hydrolyzed peptides were almost completely degraded by leucine aminopeptidase and carboxypeptidase A.

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Ultrafiltration is a treatment used to transform raw honey into a material suitable for food processing. But the operating conditions required for the efficient ultrafiltration of honey have not been obtained. The effects of dilution of honey with water, molecular weight cut-off of ultrafiltration membrane, feed flow velocity and applied pressure on the performance of ultrafiltration were examined. At the same feed flow velocity and applied pressure, the permeation rate of sugar increased with temperature and dilution of honey. The water activity of honey increased with dilution, and when the sugar concentration of honey is greater than 35.5%, the water activity is less than 0.94; such conditions inhibit multiplication of microorganisms. The flux of the ultrafiltration membranes with a molecular weight cut-off below 30000 slightly changed by alterations in the variety of honey and the pH of honey solutions, indicating that these membranes are suitable for industrial use. The optimum conditions needed for ultrafiltration were also examined in terms of energy efficiency. Less energy was needed at lower flux. The combination of feed flow velocity and applied pressure minimizing the required energy for ultrafiltration can be determined at each flux.

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Changes in volume, weight and density of Japanese radish cylinders were followed during 7-day incubation at various temperatures in NaCl solutions ranging in concentration from 0.43 to 1.83mol/l. Upon immersion of the cylinders, there was a sharp initial decrease followed by a gradual increase both in volume and weight; in contrast, the density of the cylinders increased initially to a maximum, and then decreased slowly. These observations showed that changes in volume, weight and density of the samples were dependent on both temperature and concentration of NaCl solution. These results were expressed using mathematical models with three parameters. The calculated values from a proposed mathematical model for volumetric change agreed well with the experimental values. The weight change determined in the experiment was also fitted well to the calculated values from a mathematical model similar to that for the volumetric change. In addition, it was found that the density calculated from both of the mathematical models for volume and weight changes mentioned above was also fitted well to the experimental results.

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Relationship between sensory evaluation values and the proton relaxation time, T₂, for cooked rice were investigated. Cooked rice samples with varied T₂ values were prepared by kept at 5°C and subsequently heated for various periods with microwave oven. Good correlation coefficients were obtained for the regression line of physical sensory evaluation such as firmness and glutinous with spin-spin relaxation time, although optical sensory evaluations such as gloss of cooked rice showed lower coefficients.

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The Ginkgo (Ginkgo biloba L.) is a phylogenetically old tree, and a gymnosperm of a single family, genus and species. It is a dioecism which pollinates in mid-April, and produces kinetic sperm in early September. Around the same time, its egg cells reach maturity, undergo fertilization, and become ginkgo nuts. Again, after exhibiting yellowish green buds in April, its fan shaped leaves turn green in May. The Ginkgo is also representative of such trees whose leaves turn golden in autumn. This color tone is mainly derived from the liposoluble pigmentation of carotenoid and chlorophyll. These plant pigments suppress the formation of peroxide lipids in vivo, and are attracting a great deal of attention as constituents which possess life activating function in the prevention of oncogenesis and suppression of aging. For the purposes of clarifying the activity of carotenoid and chlorophyll in the Ginkgo's botanically remarkable growth process, variations in content at time of extraction sex-specificity, and were examined. The following results were obtained: (1) At any stage in the growth process, moisture, chlorophyll, and carotenoid content was greater in the female plant. (2) Total chlorophyll and all carotenoid contents for both male and female plants were greatest in August.

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The rice with germs of Akitakomachi produced by cutting brown rice to 5% was used in this study. γ-Aminobutyric acid (Gaba) accumulated, when the rice with germs was incubated at 37°C by adding 1mM pyridoxal phosphate and 20mM glutamic acid. The optimum pH of this assay was around 6. Gaba also accumulated, when the rice with germs and Hinai homebred chicken soup were preincubated at 20, 30, 40, 50, 60, and 70°C for 1 hour, followed by the rice cooking. In the case of 60°C preincubation, Gaba increased from 4.5mg/100g rice to 16.9mg/100g rice.

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After juice sacs of Citrus unshiu was separated to membrane and serum, volatile components of each were collected using simultaneous distillation and extraction apparatus under reduced pressure, and were identified by the capillary column GC-MS. Most of terpene hydrocarbons and all paraffin wax existed in the membrane. While, terpene alcohols existed in the serum. Aldehydes existed in both part of membrane and serum. Since terpene hydrocarbons coexist with paraffin wax in a membrane, it is assumed that the aroma of canned mandarin orange is retained for the long storage period.

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Many reports on anti-mutagenicity have been made with vegetables cultivated by an ordinary manner (OV). This paper presents the results of anti-mutagenicity study of organically cultivated vegetables (OCV), using water soluble chitosan for soil improvement and leaf surface spray, in comparison with that of OV. Their anti-mutagenicity were evaluated by the forward mutation assay using Salmonella typhimurium TM677. A clear difference between the juices prepared from OCV and OV was observed in the ability to inhibit the mutagenicity of authentic mutagenic compounds, 4NQO, BaP, and Trp-P-2.

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Macrophage phagocytosis was measured using fluorescein isothiocyanate (FITC)-conjugated zymosan in 96 well tissue culture plate. The macrophage phagocytosis reaction was reached almost plateau at 30min, and appropriate dose of FITC-zymosan against 1×10⁵ cells/well of macrophages for sensitive measurement was 30μg/ml. By this method, it was clarified that extracts from some Lactobacillus casei had increasing activity of the phagocytosis, whereas all twelve vegetables extracts showed depressing activity. Especially Lactobacillus plantarum 204, had the highest activity among all Lactobacillus used in the experiment. It was suggested that the active components obtained from Lactobacillus plantarum 204 were estimated to be some sugar-like compounds, according to the results that it was water-soluble, heat-resistant, and lower molecular weight compound less than 5000 dalton.

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The amount and composition of essential oil of perilla leaves P-64 were investigated at several growing stages by using gas chromatography (GLC). The composition of essential oil components was different depending on the growth stages. The amount of essential oil components was small at the initial stage but showed high value in the middle stage, whereas in the end stage it tended to decrease. The amounts of α-pinene, β-pinene, linalool and α-caryophyllene were small, and did not have a remarkable change through the growing. The amount of perillaldehyde showed the tendency to increase although the amounts of limonene and β-caryophyllene decreased as grow up.

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