We developed “Akita-sake-komachi”, which is the rice cultivar suitable for brewing. The refined sake produced from “Akita-sake-komachi” is characterized by the taste of refined sweetness and a light finish. We tried to make “Akita-sake-komachi” local branding. In order to make “Akita-sake-komachi” of high quality, we developed a cultivation method, which enabled us to get grains with low protein content, low expression of white-berry and less crack. Since the protein of “Akita-sake-komachi” had little glutelin, it was recognized that the peptidase activity of koji (malted rice) was stronger, but that there was little amino acid generation from the steamed rice. To develop a new type of sake of “junmai-shu” using the property of “Akita-sake-komachi”, the Aspergillus oryzae “Gin-aji” was selected. The peptidase activity of the koji used by “Gin-aji” was less with “Akita-sake-komachi”. And the yeast “Akita-kobo No. 12 and No. 15” were selected for producing the “Junmai-shu” which fit to “Akita-sake-komachi” and the Aspergillus oryzae “Gin-aji”, and we commercialized “Akita-sake-komachi” brand “junmai-shu”. Accodring to the result, the product amount of the rice “Akita-sake-komachi” increased to about 2 times (2009/2005), and the shipment amount of the “Akita-sake-komachi” brand sake increased to (2009/2005) more than 3 times.

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Ashitaba, (Angelica keiskei), is a perennial belonging to Umbelliferae and has been taken as a health-promoting vegetable around the Hachijo Island area. Ashitaba has been known to contain about 20 kinds of chalcones, and two major chalcones such as xanthoangelol (XA) and 4-hydroxyderricin (4HD) are more abundantly included than other chalcones. We previously found that these two chalcones have insulin-like activities such as the induction of adipocyte differentiation and the enhancement of glucose uptake. Moreover, 4HD especially showed stronger promoting activity of glucose uptake and preventive effect on the progression of diabetes in genetically diabetic mice than the XA. In this report, we tested whether 4HD can reduce the blood glucose levels of mice which developed hyperglycemia associated with insulin resistance, and the structure-activity relationships of chalcones on glucose uptake using other Ashitaba chalcones and synthetic chalcones. As a result, 4HD showed a lowering effect of blood glucose levels of diabetic mice, probably due to the enhancement of glucose uptake. Thus, it is suggested that 4HD exert a hypoglycemic action via an insulin-independent pathway. In the structure-activity relationship, both 4′-methoxy group and 3′-large substituted group, such as prenyl, geranyl, farnesyl and benzyl of A ring were considered to be essential for glucose uptake promoting activity.

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Supercritical CO₂ extraction was carried out using finely-milled powder of Unshu Citrus peels with approximately 50μm at 333 and 353K and at CO₂ densities of 600, 700 and 800kg m⁻³. Extracts were analyzed by HPLC. Polymethoxyflavones and carotenes were detected but chlorophylls were not detected in each experimental condition. A dynamic extraction model was applied to the obtained data using solubility as a parameter and extraction curves of solutes in the peels were produced successfully. Solubilities of β-carotene, α-carotene, nobiletin and tangeletin were estimated by solubility being treated as a single fitting parameter in the dynamic extraction model. Solubility of β-carotene nearly corresponds with the value in literature (10^-8∼10^-7) and this showed the technique of estimation would be feasible for materials being unavailable. Solubility of a-carotene was found to be very close to that of β-carotene and solubilities of nobiletin and tangeletin were estimated to be double-digit higher, from 10^-6to 10^-5 in the experimental conditions.

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It was investigated if or not electron spin resonance (ESR) spectroscopy, photo stimulated luminescence (PSL) and thermo luminescence (TL) are available to detect gamma ray irradiated garlic bulb. The radiation source was ⁶⁰Co, and the dose level was 50 to 180Gy. Regarding the ESR spectra, one singlet signal of which g=2.00 was observed when analyzing the outer coat. Upon irradiation, the intensity of the singlet signal increased with the dose level. The integrated value of PSL emission of irradiated garlic bulb increased compared with that of non irradiated one. In TL measurement the glow 1 curves of irradiated samples exhibited a maximal temperature ranging from 180 to 220°C, whereas that of the non irradiated samples was 300°C, and the irradiated one was discriminated. TL glow ratio of irradiated samples and non irradiated samples were significantly discriminated when the integral temperature ranged from 150°Cto 250°C. Therefore, it was suggested that ESR, PSL and TL had possibility to be applied for detecting irradiated garlic bulb. Especially, it was concluded that TL method was practically useful for detecting irradiated garlic bulb.

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The effects of spore formation on natto qualities were investigated using the spo0A, sigH, sigE, sigF, sigK and sigG mutants of Bacillus subtilis (natto). None of mutants formed heat-resistant spores. The glutamic acid contents of the natto produced by spo0A and sigH mutants were less than that of the wild-type strain. The glutamic acid and the ammonia contents of the natto produced by the sigE, sigF, sigK and sigG mutants tended to increase, but the organoleptic tests showed that the natto produced by them were the same as for the natto produced by the wild-type strain. The natto produced by these mutants did not contain the heat-resistant spores. Therefore, these natto may have a potential to be used in the processed food industry that wants to avoid contamination due to spores.

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In this report, nutrient composition and some beneficial nutritional functions of Nigaichigo (Rubus microphyllus) fruits were described. Nigaichigo had a lower content of vitamin C compared to raspberry fruits and other popular strawberries such as Tochiotome, Sagahonoka and Akihime in Japan. Nigaichigo had a total phenolic compound content of 179.8mg/100g fresh weight, and those of raspberry fruits, Tochiotome, Sagahonoka and Akihime were 108.7, 108.5, 94.8 and 65.6mg (gallic acid)/100g fresh weight, respectively. A higher DPPH radical scavenging activity (IC₅₀) was also found for Nigaichigo (1.50mg/ml) compared to raspberry fruit (2.31mg/ml) and strawberry fruits such as Tochiotome, Sagahonoka, Akihime (2.32, 3.00, 4.25mg/ml, respectively). The high inhibitory activity against a rat intestinal maltase, a main digestive enzyme for dietary carbohydrates, was found in the fraction (40% EtEx) eluted from an adversed-phase HP-20 resin by 40% ethanol. A strong hypoglycemic activity was also found on a group given 40%EtEx in the maltose-loaded tests using normal rats. These results suggest that Nigaichigo have both strong antioxidant activity and anti-hyperglycemic potential.

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A 13-mer peptide including AVLRDC, which was one of the epitopes of monomeric and dimeric α-amylase inhibitors (AI) of wheat was designed for the antigen. The antibody to the peptide indicated high specificity to these wheat α-AIs. It was confirmed that the wheat monomeric and dimeric α-AIs and the α-AI epitopes were degraded by proteases derived from Bacillus licheniformis/I> and Streptomyces griseus using the antibody.

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