Using “unicell beans”, a food material consisting of soybeans degraded to cells by several enzymes, we developed a Natto (fermented soybean) Paste, namely, natto without bean particles, for senior citizens who have difficulty with mastication and deglutition. To prepare Natto Paste, Bacillus subtilis PN 1 strain was inoculated into autoclaved unicell beans (soybean powder consisting of degraded single cells) in 4.5 volumes of water, and subsequently fermented at 37°C for 20h. The quality of Natto Paste from an inoculum of 10⁵cells/g was judged best by organoleptic tests. Chemical analyses showed that both the nitrogen solubilization ratio and nitrogen degradation ratio of Natto Paste were higher than those of commercial natto, suggesting that protein in the former degraded more than did protein in the latter. The nattokinase activity of Natto Paste was about 4.1 times higher than that of commercial natto. Organoleptic tests of Natto Paste were carried out by attendees of two senior citizen centers in Chiyoda-Ward, Tokyo. Natto Paste scored better than commercial natto on all items except “appearance” (p<0.05), the only aspect that required further improvement. This may have been due to the fact that Natto Paste differed from the expected image of natto. The above results showed that the Natto Paste developed in this study had a high protein content and appeared to be easy for senior citizens with difficulties in mastication and deglutition to eat. A high food functionality, similar to that of commercial natto, is expected.

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Lactoferrin can solubilize over 200 molar equivalents of iron, and is expected as a natural iron solubilizer for food products and nutraceuticals from the viewpoints of bioavailability, safety, and productivity. To investigate the availability of iron solubilized by lactoferrin (FeLF) in humans, we recruited thirteen volunteers with serum hemoglobin values below 13g/dl blood and/or ferritin levels below 45ng/dl serum and served them a supplement containing FeLF (7.5mg of iron) every day for twelve weeks. Significant increases in blood hemoglobin (Hb), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and serum ferritin concentrations were observed during the FeLf supplementation period. The hemoglobin level of three anemia subjects improved significantly during the period of FeLf supplementation, and, conversely, decreased after discontinuation of the supplementation. No side effects attributable to FeLf supplementation were observed either during or after the supplementation period. Thus, the results suggest that FeLf could be a useful food product for iron fortification to prevent anemia without the risk of toxicity often encountered with general iron supplementation.

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Previously, we reported that potato tubers and common potato snack products contain GABA, and oral administration of certain types of potato snack products currently on the market reduced blood pressure in spontaneously hypertensive rats. In this study, we examined methods to increase the GABA content of &ldquoTOYOSHIRO” potato tubers, as measured by HPLC. Treatments used to increase GABA levels were sprouting, anoxic conditions (nitrogen displacement, soaking in various solutions), freezing and GABA substrate coenzyme addition. Sprouting treatment increased GABA levels by approximately 1.3 times. In the anoxic conditions, GABA increased over three times after three days exposure to a nitrogen atmosphere, during which time glutamic acid in the tubers was converted into GABA, but only about two times after soaking in various solutions (water, salt solution, citrate solution, ethanol) for two days. GABA levels increased 3 times after freezing treatment, 2 times by trituration treatment at 35°C, and over 3 times by co-treatment with glutamic acid, a substrate of GABA, and coenzyme pyridoxal 5'-phosphoric acid. These results indicate that GABA content of potato tubers was increased 2∼3 times by several anoxic conditions, freezing, and trituration treatment.

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Physical properties of the viscous material contained in natto fermented at various fermentation temperatures were investigated by dynamic viscoelasticity measurement and statistical tensile test. The viscous materials of natto prepared at 40 and 45°C were judged superior by sensory evaluation to those prepared at other temperatures, although no differences were found by the statistical tensile tests and E" values of the dynamic viscoelasticity modulus. However, materials prepared at 40 and 45°C had a lower tan delta (=E′/E") value, and a negative correlation (r=−0.90) was found between sensory evaluation and tan delta values. The results suggest that the tan delta value of dynamic viscoelasticity is a useful index for evaluating the fermentative condition of natto.

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The water extract of raw mushroom Auricularia auricula (Kikurage) was precipitated by 50-70% ammonium sulfate, and the precipitate inhibited accumulation of triglyceride in mouse 3T3-L1 preadipocyte. Fractions of precipitate by anion-exchange column chromatography suppressed differentiation of 3T3-L1. The active fractions contained several proteins with molecular weights of over 10000.

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Seed coat of tamarind (Tamarindus indica L.) cultivated in Thailand was extracted by three organic solvents at different temperatures, with and without sonication. Antioxidant properties, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, reducing power, and ferrous ion chelating ability, were investigated. Ultrasonic extraction at 40°C, using methanol or ethanol as the extracting solvent, was found to posses strong antioxidant activities.

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