The preventive effects of dietary bilberry extracts (B ext), which contained fifteen species of anthocyanins, on oxidative stress induced by feeding paraquat (PQ) were assessed in rat. Growth retardation and lung enlargement due to feeding the rats a diet containing PQ were markedly suppressed by supplementing B ext. Also the decrease in triacylglycerol and increase in TBARS by feeding PQ were also suppressed by administration of B ext. Although there was no significant difference in the total concentration of cholesterol in plasma, elevation in the arteriosclerosis index due to PQ was decreased by administration of B ext. HDL-cholesterol was decreased by feeding PQ but was increased by B ext. In addition, superoxide dismutase and glutathione peroxidase activities in the erythrocyte of rats were decreased by feeding PQ, and these decreases were relieved by administration of B ext. Catalase activity in erythrocytes in the PQ group was increased, and this level was fur then increased by feeding B ext. In the liver, B ext. also suppressed the decrease in catalase and the increase in glutathion peroxidase activities in the PQ-fed rats. These results suggest that B ext. functions to prevent oxidative stress in rats due to PQ.

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“Gomazou” is an improved high-lignan breed of sesame which contains large amounts of sesamin and sesamolin. The object of this study was to identify new lignans other than sesamin, sesamolin and lignan glycosides, and to determine changes in their levels and functions. For comparison of different types of sesame seed, we used Gomazou, Kanto No. 1 and Chinese white sesame seeds. The contents of sesamin and sesamolin in Gomazou were 848mg/100g and 280mg/100g, respectively, which are 2.1 and 1.3 times higher than those of Kanto No. 1. Kanto No. 1 had a higher sesaminol content than Gomazou. Treatment with 1N-HCl to analyze the bond type of lignan revealed an increase in the peak numbers and areas of polar compounds in Gomazou. The content of sesaminol in Gomazou was 1.6 times that of Kanto No. 1. These results suggest that Gomazou contains a larger amount of lignan glucosides than Kanto No. 1. The contents of sesamin and sesamolin decreased and those of polar compounds increased after germination, and DPPH radical scavenging activities, SOD activities and ORAC values in methanol extracts were enhanced. Polar compounds were correlated (correlation coefficient=0.849, p<0.01) with DPPH radical scavenging activity. Analysis by LC-MS revealed that among the six main lignan compounds whose contents increased, five were known compounds and another was an unknown compound that showed DPPH radical scavenging activity.

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Effect of hot water-extracted Boysenberry leaf was studied on spontaneous contraction in rat uterus specimens in vitro. Extraction of 100g of Boysenberry leaf using 2L of hot distilled water yielded 30.2g of dried extract. This extract dose-dependently enhanced the force and frequency of contractions. These changes were dose-dependently inhibited by the cumulative addition of diltiazem, an L-type calcium channel blocker. Dantrolen, an inhibitor of the release of calcium from the endoplasmic reticulum, markedly inhibited only the frequency of contraction. These findings show that hot water-extracted Boysenberry leaf stimulates the spontaneous contraction of the uterus by enhancing an influx of extracellular calcium into the smooth muscle cells, probably through voltage-dependent calcium channels. Based on the above findings, it was found that hot water-extracted Boysenberry leaf affects uterus function.

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The Tokyo X pig was created by breeding Duroc, English Berkshire and Beijing Black pig types. The sensory and physicochemical properties of Tokyo X pork were compared with those of regular pork (LWD) and English Berkshire. Quantitative descriptive analysis (QDA) was applied to depict the sensory properties of three pork samples using nine trained panelists. Preferences in smell, texture and overall quality were evaluated by 69 consumers using a nine-point hedonic scale. For each pork sample, textural properties and types of volatiles present were analyzed by texturometer and dynamic headspace GC-MS, respectively. The QDA panel selected eight attributes : roasted, fishy, sweet, animal aroma, umami, fattiness, hardness and juiciness. LWD pork was found to be significantly (p≤0.05) harder than Tokyo X pork ; this result was supported by the texturometer profiles. The animal odor of Tokyo X pork was significantly (p ≤0.05) weaker than those of the other two pork types. GC-MS analysis showed that the amounts of saturated and unsaturated C5, C6 and C7 alcohols and aldehydes in Tokyo X pork were small compared to the other types. In terms of consumer preferences in texture, Tokyo X pork surpassed the other two types by a significant margin (p ≤0.05).

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Recently, we identified novel saponins from edible seeds of Japanese horse chestnuts (Aesculus turbinata BL.) obtained during processing of the seeds with wooden ashes which was intended to remove harshness. In the present study, we isolated saponins and related compounds from natural and edible seeds, and examined the attenuating effect on increasing levels of blood glucose using male ICR mice. All of the deacetylescins Ia, IIa, Ib, and IIb were similarly effective in attenuating glucose levels and were less potent than the natural escins. Experiments on escins and related derivatives revealed that the potency of the compounds in the attenuation was in the order of escins>deacetylescins>desacylescins. The findings suggest that the acyl moiety at C-21 and the acetyl moiety at C-22 are important in attenuating increasing levels of blood glucose. Escin and related substances exhibited much weaker inhibitory activities on α-amylases as compared with (-)-epigallocatechin gallate. In addition, those compounds showed almost no inhibition of intestinal α-glucosidase activity. The results indicate that escins and their derivatives have little ability to inhibit the digestive enzymes for saccharides. The saponin fraction which includes deacetylescins and desacylescins as major components obtained from edible seeds was much less bitter taste than escins from natural seeds at the same concentrations. Taken together, deacetylescins and desacylescins from edible seeds seem to be useful as sources of nutraceutical foods because of their activity in attenuating increasing levels of blood glucose as well reducing the bitter taste.

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In a reusing process of waste okara by the incorporation into tofu, the treatment of the okara hydrolysate (okara milk) and original soymilk mixture with transglutaminase (TGase) is required for the complete gelation of whole soymilk. To perform this enzymatic treatment economically, several immobilized microbial TGases were prepared with three support types and bioselective complexation between avidin (A) and biotin (B). The enzymatic activity of the immobilized TGase was either determined by benzoyloxycarbonyl-L-glutaminyl-glycine and hydroxylamine or the whole soymilk as a substrate (50°C, 30min). Of the prepared enzymes, the TGase immobilized on Lewatit VP OC 1065 resin, Lew-B-A-B-TGase, was selected as a practical biocatalyst given that it exhibited the highest specific enzyme activity. A breaking test of tofu prepared from the whole soymilk treated by Lew-B-A-B-TGase, with conventional coagulants such as glucono-δ-lactone showed an increase in breaking strength compared to untreated samples. In addition, the same immobilized TGase exhibited good operational stability, maintaining 100% of its initial activity even after 10 cycles of cross-linking of the soy proteins in the whole soymilk.

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We prepared new oligosaccharides from corn fiber by partial hydrolysis. The oligosaccharides contained both neutral and acidic components, with the former consisting mainly of mixtures of arabinoxylo-oligosaccharides and xylooligosaccharides, while the latter were occurred primarily as glucronoxylooligo-saccharides. In this study, we investigated the physiological effects of our oligosaccharides in rats fed diets containing the oligosaccharides at 2%, 4% or 6% for 4 weeks. The weight of the cecum, the proportion of Bifidobacterium in cecal contents, and fecal water content were all found to have increased significantly. The pH of cecal contents decreased significantly in rats fed the oligosaccharides. These results show that the oligosaccharides may selectively enhance the growth of Bifidobacterium in intestine and improve intestinal microbial balance. Adipose tissue decreased significantly in rats fed the oligosaccharides. There were no significant differences in the concentrations of serum lipids between the control group and the group, fed oligosaccharides, although serum triacylglycerol levels tended to decrease in response to oligosaccharide administration. It therefore appears that the intake of oligosaccharides may influence lipid metabolism. Bifidobacterium in intestinal microbiota are useful for maintaining good health of the host. These results indicate that the oligosaccharides from corn fiber might have equivalent physiological effects in humans.

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We have observed that dose-dependent tumor-growth inhibitory activity of Buna-shimeji mushroom, Hypsizigus marmoreus, against murine Sarcoma-180 (S-180) was observed by the administration of 5% and 10% powdered fruiting body-mixed feed (dose of fruiting body, ca. 16mg/kg/day). Moreover, we have found that ethyl acetate-extract from the powdered fruiting body also exhibited tumor-growth inhibitory activity. Approximately 3g of the active substance (acetone-eluting fraction) was obtained from 250g of powdered fruiting body by the silica gel fractionation. Following the administration of the acetone fraction (ca. 250mg/kg/day), equivalent to the dose present in 10% powdered fruiting body-mixed feed, the tumor volume of solid S-180 was 41.5% compared to that of control mice that were fed only CE-2. The acetone fraction also exhibited similar inhibitory activity against syngeneic IMC carcinoma. The main active substance of the acetone fraction was subsequently identified as the tandem-type polyterpene (C₄₅H₈₆O₇) by NMR and MS analysis. In addition to the murine tumor cells, S-180 and IMC, we have found that this terpene fraction exhibits cytotoxicity against various human tumor cells, U937, MKN45 and HL-60. Moreover, the purified active substance (C₄₅H₈₆O₇) was observed to induce apoptosis in HL-60 cells, and it was suggested that this activity might also exhibit the tumor-growth inhibitory activity.

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To examine the possibility of using quinoa fermented with Rhizopus oligosporus (known as quinoa-tempeh or Q-tempeh) as an ingredient for daily-use food, soft and hard biscuits were prepared using soft flour and medium flour partially substituted with powdered quinoa and Q-tempeh, respectively. The physical properties, palatability and iron and α-tocopherol contents of the biscuits were compared with those of control biscuits prepared using 100% soft flour and medium flour. It was found that substituting 20% of the flour with powdered Q-tempeh or quinoa did not alter the thickness or volume of either type of biscuit.
Substitution with quinoa powder did not affect the sensory evaluation scores of either type. Substitution with Q-tempeh powder resulted in higher sensory evaluation scores for brittleness and taste in soft biscuits, but the reddish surface color became slightly stronger.
Thirty-percent substitution of flour with powder of quinoa and Q-tempeh resulted in a decrease in volume and hardness in both types of biscuit. Biscuits prepared with quinoa powder-substituted flour were given lower sensory evaluation scores in terms of the overall acceptability of hard biscuits due to their low solubility in the mouth, but substitution with Q-tempeh powder did not have the same effect. The iron and α-tocopherol contents of biscuits made with flour containing 20% Q-tempeh powder were more than 2.5 times higher than those of control biscuits. The absorption of iron from Q-tempeh powder was found to be higher than that of quinoa powder in rats for partial digestion of phosphoric compounds. These results suggest that Q-tempeh powder is more suitable than quinoa powder as an ingredient of biscuit, and may be added to flour in amounts of up to 20%. Moreover, Q-tempeh powder may be used to increase the iron and α-tocopherol contents of food products.

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Samples frozen surimi (ground fishmeat) with different moisture and cod oil contents were subjected to measurements of fracture stress (bending fracture energy) in a low temperature range (below 0°C). The optimum conditions for low-temperature cutting (“cryo-cutting”) were estimated based on the enthalpy changes measured by a differential scanning calorimeter (DSC).
Frozen surimi samples with moisture contents of 60∼90% and containing 1∼20% cod oil, which had frozen at -40°C, could not be cut by bending, but they could be cut at -80°C (temperature A). The melting temperature of cod oil, as determined by DSC measurement, but they was above -80°C. Thus, the surimi could be cut below the melting temperature of cod oil as detected by DSC.
No significant decrease in the bending fracture energies of the surimi samples were measured below temperature A, and a glass transition was not observed on the DSC chart. It was considered that the presence of cod oil preverts glass transition in the surimi sample, because the melting temperature of cod oil overlaps with the glass transition range of surimi without oil.
The results showed that the optimum cutting temperature was below -80°C, and that it could be estimated by DSC measurement.

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Upon heating at 100°C, microbial transglutaminase (MTG) suppressed coagulation of whey protein concentrate (WPC) solution, decreasing solubility and increasing viscosity, particularly with addition of 30 units of MTG. Creep testing of the gel prepared by treating freeze-dried WPC with 10 units of MTG showed that the WPC gels decreased in instant elasticity E₀ and that the ratio of Newtonian viscosity, η_N, for E₀ increased. WPC gels treated with MTG increased their water-holding capacity. In MTG treatment of WPC solution, low crosslinkage was observed at high concentration and at low pH. These observations are assumed to be due to the molecular structure of the WPC. It is suggested that heat tolerance is conferred on the WPC with treatment by MTG, and that this property seems to arise due to crosslinking between α-lactalbumin and β-lactoglobulin, two main milk proteins.

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The growth behavior of Zygosaccharomyces yeasts in commercial beverages was investigated. In beverages with high sugar contents, such as high-sugar tea, fruit juices, beverages containing lactic acids, and sports drinks, excellent cell growth and generation of large amounts of CO₂ gas were observed. In contrast, cell growth was very slow and little gas generation was observed when Zygosaccharomyces yeasts were grown in beverages with low sugar contents, such as low-sugar tea and green tea. Cell growth in high-sugar tea was found to increase in parallel with increasing growth temperature. These results suggest that yeast growth and gas generation in beverages contained in previously opened PET bottles may result in explosions.

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