We determined stable carbon, nitrogen, and oxygen isotopic compositions (δ¹³C, δ¹⁵N and δ¹⁸O) of blanched and salted wakame (Undaria pinnatifida) from major cultivation areas in Japan (Naruto and Sanriku), China and South Korea to evaluate whether the isotopic compositions could be used to identify the geographical origin of blanched and salted wakame. A total of 209 samples from three different plant parts (top, middle, and bottom) were analyzed for carbon and nitrogen isotopic compositions. In addition, 77 samples (top, middle, and bottom) were analyzed for oxygen isotopic composition. The variations in the isotopic compositions ranging from 0.2 to 2.0‰ for carbon and 0.1 to 1.4 ‰ for nitrogen are found between different parts of a single wakame plant, which is small enough to discriminate Naruto wakame (−16.6±0.9‰, mean±1σ for carbon and 10.7±1.1‰ for nitrogen) from the wakame of other regions (−17.1±1.9 ‰ for carbon and 1.7±2.8‰ for nitrogen). Indeed, linear discriminant analysis revealed that 98.4 % of Naruko wakame can be distinguished from the other regions. However, no marked differences in the oxygen isotopic composition was observed between wakame from Naruto (19.3±0.8‰, mean±1σ), Sanriku (18.3±0.6‰), China (19.1±0.9‰), and South Korea (20.4±0.5‰). We conclude that the carbon and nitrogen isotopic compositions are potentially useful for discriminating between wakame from Naruko and wakame from other areas.

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The leaching losses of potassium from taro and yam during soaking in hot water were examined at four temperatures ranging from 70°C to 100°C. In order to describe this phenomenon quantitatively, the leaching losses and measured data were fitted to the infinite cylinder diffusion model using a non-linear least squares method. Therefore, the measured results agreed well with the calculated results. The values of the estimated diffusion coefficients were 0.94±10⁻⁶ to 1.34±10⁻⁶ in taro and 1.41±10⁻⁶ to 1.60±10⁻⁶ (m²·s⁻¹) in yam, and the apparent activation energies determined from an Arrhenius-type equation were 12.6 and 4.9 (kJ·mol⁻¹), respectively. The applicability of microwaving for blanching taro and yam was also examined. Changes in enzyme (peroxidase) activity, color, hardness, weight and potassium content were compared for three blanching methods (microwave radiation of wrapped and unwrapped samples and immersion in boiling water). Microwave blanching of wrapped samples required the least time for enzyme inactivation. Color differences (ΔE) after blanching were 5.3-11.7 in taro and 15.9-19.0 in yam. Samples became significantly softer after microwave blanching, and wrapping reduced weight loss during microwave heating. While samples heated by immersion in hot water lost a large amount of potassium, microwave blanching did not result in loss of potassium. These results suggest that microwaving is useful for blanching taro and yam.

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To confirm the effect of Young Barley Leaf Powder (YBLP) on hypercholesterolemia, we performed a pre-clinical study involving diet-induced hypercholesterolemia in rats and a clinical study in healthy subjects. The pre-clinical study used three experimental groups : Wistar rats were fed a normal diet, a high cholesterol diet (HCD), or a HCD with 4% (w/w) YBLP for 4 weeks. In the clinical study, fifteen healthy subjects, with mean total plasma cholesterol of 205.1 mg/dL, were supplemented with a powdered drink containing YBLP for 12 weeks. The clinical study was of a preliminary open-label design. Following treatment, lipid parameters were analyzed in the rat and human plasma. The results indicated that total plasma cholesterol and LDL cholesterol were decreased, in both the pre-clinical and clinical studies, following ingestion of YBLP. Additionally, the ability of YBLP to absorb bile acids was examined. YBLP, and residual substances after hexane extraction, were observed to strongly absorb bile acids. These results suggest that YBLP could improve hypercholesterolemia due to its ability to absorb bile acids.

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Barley grown in test fields and harvested in June 2011 was roasted and brewed. The translocation of radioactive cesium from roasted barley to tea was examined at various brewing times. Roasted barley was boiled for 5 min at a ratio of 1.5 L water : 50 g grain, and allowed to brew for 5, 60 and 120 minutes. The concentration of radioactive cesium (¹³⁴Cs and ¹³⁷Cs) in the barley tea and residual grain were determined by gamma-ray spectrometry with Ge-semiconductor detector. The translocation of radioactive cesium from roasted barley (138Bq/kg) to tea extract was about 38 % at 120 minute extraction and the radioactive cesium concentration of the barley tea was 1.83Bq/kg. Thus, it was confirmed that even when 100Bq/kg barley was used as an ingredient, the radioactive cesium concentration of barley tea made with the standard formula was much lower than 10Bq/kg, the standard limit for water and drinks.

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Large amounts of purple-colored liquid waste containing nasunin are generated by plants manufacturing lightly salted eggplant products (Asa-zuke). We studied a method for the preparation of antioxidative powder from the liquid waste of brined eggplant. In order to recover nasunin from the waste, various synthetic adsorbent materials, such as HP-20 and SP-207, were examined for their adsorptive abilities ; HP-20 was found to have the best ability to adsorb nasunin. By using this absorbent, ca. 96% of sodium chloride and ca. 99% of aluminum in the liquid waste were eliminated, and the adsorbed nasunin was desorbed with 5mol/l acetic acid solution. The desorbed fraction was freeze-dried to give a fine purple powder. About 13g of the powder was obtained from 30 liters of waste pickle, and contained about 2 g of nasunin and 1g of chlorogenic acid. The ORAC value for the powder was estimated to be about 10432μmol trolox equivalent/g, which was comparable to 69% of that of chlorogenic acid. From the results, it was concluded that the combination method with HP-20 and 5mol/l acetic acid, as elution liquid, can be used for effective preparation of nasunin-containing antioxidative powder from liquid waste of brined eggplant.

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The characteristics of flavonoid, phenylpropanoid, and coumarins in Bonin Island lemons (Kikuchi lemons), ranging in maturing from low to high, were examined and subsequently compared to those of Meyer lemons, Eureka lemons, and Satsuma mandarins. A distinctive compound, 7-methoxy-5-prenyloxycoumarin, was isolated from the Kikuchi lemons. Hesperidin was the main flavonoid found in Kikuchi lemons. Meyerin was detected in Kikuchi, Meyer, and Eureka lemons. The flavedo of Kikuchi lemons had a higher content of both 5,7-dimethoxycoumarin and 7-methoxy-5-prenyloxycoumarin than the flavedo of Eureka lemons. The flavonoid, phenylpropanoid, and coumarins characteristics in Kikuchi lemons were similar to those of Meyer lemons.

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The anti-hyperglycemic functions of Adzuki beans Vigna angularis cotyledon were examined in vitro. Various Adzuki beans with or without seed coats were boiled and crushed, then hydrolyzed with pepsin at 37°C for 30min. The Adzuki bean hydrolysates (4.2mg/ml) inhibited the activity of alpha-glucosidase prepared from rat intestinal powder by 18.9% to 29.0% as compared with the control. This inhibitory effect was not diminished by trypsin treatment. In addition, the hydrolysates (10mg/ml) induced glucagon-like peptide-1 (GLP-1) secretion in a murine enteroendocrine cell model. These activities were found in the hydrolysates prepared from the beans without seed coats as well as those with seed coats. These two effects of Adzuki bean cotyledon hydrolysates, namely, inhibition of alpha-glucosidase activity and induction of GLP-1 secretion, suggest the potential application of Adzuki beans hydrolysates to a functional food material for preventing hyperglycemia.

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In vitro and in vivo digestion experiments were carried out with soft and hard types of rice crackers and cooked rice. Both types of rice crackers produced significantly more sugar than cooked rice at 60minutes after the start of the in vitro reaction. Rice crackers and cooked rice were consumed by seven subjects. Both types of rice crackers led to higher blood glucose levels ( p<0.05) than did cooked rice at 15 and 30minutes after consumption. The digestion rate of rice crackers may be the result of gap formation, a higher specific volume and starch degradation.

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The effect of brine powder on dynamics of radioactive cesium during cooking of Chinese noodles was investigated. Two kinds of Chinese noodles, with and without brine powder [brine powder noodle : 1.3% (w/w) brine powder (potassium carbonate 60% (w/w) and sodium carbonate 40% (w/w)), NaCl noodle : 1.3% (w/w) NaCl was substituted for brine powder], were prepared, and the transfer property of radioactive cesium and firmness of noodles were compared. (1) The transfer ratio of radioactive cesium into broth in the brine powder noodle (47%) was significantly lower (p<0.01) than that in the NaCl noodle (67%). (2) The deformation load of the brine powder noodle showed significantly greater firmness (p<0.05) than that of the NaCl noodle in both raw and boiled states. These results indicate that brine powder suppresses the transfer property of radioactive cesium from noodle into broth during cooking. Moreover, brine powder contributes to the enhancement of noodle firmness. Thus, suppression of the transfer property of radioactive cesium is thought to be due to the enhancement of firmness by brine powder.

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