The purpose of this study is to improve the indicator of temperature-raise to be able to store at room temperatures. The indicator was applied with sol-gel reaction by using gelatine, sodium chloride and food dye. The indicator warned by developing color after 14 hours at 20℃, after 72 hours at 10℃ and after 96 hours at 4℃. It was suggested that the indicator could regulate the period to develop color by changing sodium chloride concentrations.

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Two phenolic compounds identical to the tea catechin metabolites produced by mammalian intestinal bacteria were isolated from a post-fermented tea produced in Japan. The compounds were determined as (2S)-1-(3',4'-dihydroxyphenyl)-3-(2",4",6"-trihydroxyphenyl)-propan-2-ol and (2S)-1-(3',4',5'-trihydroxyphenyl)-3-(2",4",6"-trihydroxyphenyl)-propan-2-ol by spectroscopic methods. In addition, pyrogallol was also isolated as a metabolite of gallic acid. The catechin metabolites and pyrogallol were detected in post-fermented teas produced in Tokushima, Kochi and Ehime prefectures. Tea epigallocatechin-3-O-gallate and epicatechin-3-O-gallate disappeared in the teas produced in Kochi and Ehime prefectures; instead; gallocatechin and catechin significantly increased. In contrast, the galloylated catechins remained in the tea produced in Tokushima region. The catechin metabolites were not detected in the post-fermented tea produced in Hunan, China, by aerobic microbiai fermentation.

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The purpose of this study was to develop indicators, which are low cost and user-friendly, for warning temperature rising in cold chain. The color of Food Blue No.2 in glycerol aqueous solution changed from blue to light yellow. To apply this behavior, the aqueous solution was packed into transparent plastic bag with various concentration of glycerol. An indicator containing 0.01% Food Blue No.2 in 60% glycerol warned by changing color after 135 hours at 4℃. An indicator containing 0.01% Food Blue No.2 and 0.01% Food Red No.2 in 60% glycerol warned by changing color after 156 hours at 4℃. As a result, it showed that an ability to develop a new type indicator using Food blue No.2

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In 2004, an outbreak of serious acute encephalopathy exclusively occurred in patients with chronic kidney diseases after the intake of basidiomycetous wood rotting fungus Pleurocybella porrigens. The exact factors that induced encephalopathy by this mushroom remain unknown partly due to its extreme slow growth. We attempted to develop media suitable for vegetative growth of P. porrigens for application in various fields. Fifteen isolates of P. porrigens collected from rotting conifers, Cryptomeria japonica and Pinus densiflora, in different geographical areas in Japan were cultivated on potato dextrose agar (PDA) medium; large variation in growth rate and colony features was observed among these isolates. The five isolates with the best growth rates were then cultured in five kinds of liquid media, potato dextrose (PD) medium, malt extract・yeast extract (MY) medium, potato extract・carrot extract (PC) medium, Amazake medium, and Ohta's medium at 20℃ in the dark. Dry biomasses of the isolates cultured in the liquid media were determined after 8 weeks of static cultivation. Among the tested liquid media, PD medium was the most suitable for biomass growth, followed by Ohta's, MY, Amazake and PC media. The average biomass growth of the isolates cultured in the synthetic medium (Ohta's medium) was 20-92% of that in PD medium. Remarkably large biomass variation was also observed among the isolates cultured on each liquid medium. Mycelia of this mushroom had abortive lateral branching at high frequency which could be one reason why this mushroom grows very slowly. Moreover, the Japanese population of P. porrigens has large variation in vegetative growth. Taken together, elucidation of the possible association between its chemical constituents and the onset of encephalopathy may be possible by culturing isolates with high growth ability on PD medium as a natural medium and Ohta's medium as a synthetic medium.

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In order to propose effective preparation methods for natural antioxidant food additives, variations in the marker constituents and antioxidative potencies of extracts depending on different extraction methods were estimated. Several extracts were prepared using different solvents from the leaves of Salvia officinalis (Sage), fruits of Foeniculum vulgare (Fennel), and Houttuynia cordata (Dokudami) which are the raw materials of natural food additives. Their antioxidative potencies and marker ingredients were estimated based on the oxygen radical absorbance capacity (ORAC) and HPLC analysis. Among the various extracts prepared from sage, the 50% aqueous ethanolic (EtOH) extract, which contained rosmarinic acid as the major component, showed high antioxidative potency. The EtOH, aqueous EtOH and other extracts of fennel showed antioxidative activities weaker than the other tested materials. The fraction including a volatile oil of fennel showed weak antioxidative activity, therefore it was suggested that the active constituents were contained in the polar fractions. Syringin (sinapyl alcohol 4-O-β-D-glucoside) and quercetin 3-O-β-D-glucuronide were identified as the major constituents of the fennel extract. In the dokudami extracts, the 50% aqueous EtOH extract showed a high antioxidative potency, which was suggested to be responsible for the quercitrin (quercetin 3-O-α-L-rhamnoside) of the major constituent.

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Chondroitin sulfate (CS) is the main constituent of the cartilage and used as a medicine for joint pain. Many kinds of health foods including CS are used for the potential effect of alleviating joint pain. In order to evaluate the quality of CS in Japanese health foods, the origin and content of CS were investigated using health foods of great sales volume in Japanese and US markets by three methods: a) conducting disaccharide compositional analysis after enzymatic depolymerization, b) molecular weight determination using gel permeation chromatography, c) purification of CS in the products by ethanol precipitation and by complex formation with cetylpyridinium chloride. All Japanese health foods indicated usage of the fish origin of CS in labels; however, one of them was estimated usage of the mammal origin of CS obtained by the disaccharide composition and the molecular weight of CS. On the other hand, all US health foods were estimated using only the mammal origin of CS. The CS contents in the Japanese products obtained by the purification method were from 21mg/day to 214mg/day and the US products were from 396mg/day to 475mg/day. Therefore, the CS contents in the Japanese products were revealed to be less than those in the US products. In addition, the percentages of the measured CS content against the labeling CS content were from 53% to 99%. One of the Japanese products contained only 21mg/day of CS, however it indicated "Chondroitin" written in big and flashy letters in the label. The manufacturers, who sell health foods of poor qualities, have to improve quality control system and carry out thorough quality test of raw materials and final products. In order to protect consumers, we think that the mandated Good Manufacturing Practice (GMP) has to be introduced into the health food industry and authority should require all manufactures in the industry to keep GMP.

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As a part of development of profiling anlysis for raw material in the health foods, sixteen kinds of Setsucha products purchased from the Japanese market were performed principal component analysis (PCA) based on the bucket integration of ¹H NMR spectra. The results of metabolome analysis by PCA in ¹H NMR spectrum showed a characteristic signal at δ 3.66 due to a sterol derivative. This signal was indicated to be existence of a reference compound to distinguish among Setsucha products. These data was different from the profiling results by HPLC analysis with UV detection and taste-sensing system. However, by limiting analysis range of ¹H NMR spectrum into three regions observed in three reference compounds identified by HPLC analysis, the metabolome analysis by PCA confirmed a similar classification result to HPLC profiling.

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A simple and efficient methd for the determining of 15 kinds of isoflavones in kuzu starch and kuzu leaf has been developed by means of high performance liquid chromatography. Isoflavones were extracted with 70% ethanol in ultrasonic bath for 30min. Isoflavones were separated on a Inertsil ODS-3V column (5μm, 4.6mm i.d.×150mm) using 0.1% formic acid solution in water and acetonitorile as a mobile phase. The injection volume, flow rate and column temperature were 10μL, 0.8mL/min and 40℃, respectively. A UV absorbance detector was set to 254nm. The determination limit of each isoflavone was 0.02μg/mL. Crude and commercially available kuzu starches contain a large percentage of daidzein. The range for contained daidzein in crude kuzu starches is from 42.1 to 455μg/g and in commercially available kuzu starches is from 34.4 to 75.7μg/g. Kuzu leaves contain a large percentage of glycitin, 6"-O-malonylglycitin and glycitein. Kuzu leaves also contain only a few puerarin, although kuzu roots contain a large amount of it.

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