We examined effects of single intake of an extract of seeds of evening primrose (EPE) on postprandial blood glucose levels on 16 healthy nondiabetic subjects (9 males and 7 females, age 32.6±10.4) and 18 subjects suffering mild diabetes and borderline diabetes (15 males and 3 females, age 53.5±7.1). After 5min of administration of EPE or placebo, the subjects were given cooked rice by crossover design. In the all subjects, the rises of postprandial blood glucose levels were reduced, by EPE ingestion compared to those by placebo ingestion. Furthermore, the rises of postprandial blood insulin levels were reduced by EPE ingestion, compared to those when placebo taking. These results suggest that the EPE may be a useful food ingredient for prevention of diabetes mellitus.

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Protease digested royal jelly (ProRJ) proved to inhibit angiotensin I converting enzyme (ACE) activity in vitro. And we have demonstrated that peptides isolated from ProRJ (Ile-Tyr (IY), Val-Tyr (VY)) also inhibited ACE activity. We examined an antihypertensive effect of RJ, ProRJ and RJ peptides (IY and VY) on spontaneously hypertensive rat (SHR). In chronic oral administration of ProRJ and RJ at the dose of 10mg/kg/day for 28 days, the systolic blood pressure (SBP) of SHR was significantly decreased against the control. The blood pressure of normotensive rat (Wistar Kyoto rat) did not changed on the repeated administration of ProRJ. In repeated oral administration of RJ peptides at the dose of 10mg/kg/day for 28 days, SBP was significantly reduced against the control. These results suggest that the hypotensive effect of ProRJ is correlated with ACE inhibitory activity of RJ peptides, and ProRJ would be beneficial for improving blood pressure in hypertension.

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The effect of protease-treated royal jelly (PRJ) on plasma and liver lipids in rats fed a high fat plus high cholesterol (F) diet was investigated in comparison with untreated royal jelly (RJ). The amount of total cholesterol in plasma, which was increased by the F diet, was decreased by royal jelly medication. That lowering effect of cholesterol level in PRJ group was more markedly than that in untreated RJ group. The ratio of plasma HDL-cholesterol to total plasma cholesterol in PRJ group was increased more effective than that in untreated RJ group. Although the amount of total cholesterol in the liver was declined by royal jelly medication, there was no significant difference of its tendency between PRJ and untreated RJ groups. The amounts of fecal excretion of cholesterol and bile acid increased in the F group, those excreting amounts were enhanced by the addition of royal jelly, especially, those in PRJ group were significantly higher than those in F group. These results suggest that the lowering effect of cholesterol in rat plasma by PRJ is due to an increase of the fecal excretion of cholesterol and bile acid, and that PRJ is more valuable than RJ.

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The production of Matcha for processed food is increasing in recent years. However, Matcha has many problems for use in processed food, such as bad suspension, color deterioration, and high costs. We developed fine Matcha to overcome these problems, and investigated its properties. Fine Matcha was produced by two methods: classification of normal Matcha, and crushing by jet-mill. The particle size of normal Matcha ranges widely from 1μm to 100μm, but that of fine Matcha has a narrow range of from 1μm to 20μm. The particle diameter of fine Matcha is 3.2μm, and that of normal Matcha is 11.5μm. Fine Matcha suspended in water has a smaller sedimentation rate than normal Matcha. In addition, fine Matcha used in buckwheat noodles (soba noodles) improved the colorimetry of the noodles in comparison with normal ones. Finally, fine Matcha added to dough was found to cause the bread to rise better than normal. Thus, fine Matcha is useful for processed food in producing less sedimentation, improving the colorimetry, and augmenting the rising of bread dough.

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In order to develop a novel food utilization technique using germinated brown rice (GBR), an extrusion of GBR by twin-screw extruder was investigated. Compared with polished rice and brown rice, prepared GBR (cv. Koshihikari) for supplying extrusion cooking, contained significantly higher gamma-aminobutyric acid (GABA). Operating conditions for extrusion of GBR, were barrel temperature at 150°C, feed rate for 100g/min and pressure at 6.0MPa. For the evaluation on the extrudate of GBR, as to nutritional component, rupture strength, particle size, color and viscosity, were measured. Rupture strength on extrudate of GBR was lower than that of polished rice, and it was like a snack food. Mean particle diameter for the extrudate powder of GBR was finer than that of unextruded brown rice. It contained higher functional components, GABA, oryzanol, inositol, dietary fiber and total ferulic acid, and also contained richer tasty amino acids, such as glutamic acid, glycine, alanine, aspartic acid, than unextruded polished rice. As the results of panel test on bread mixed 30% of extruded GBR powder, sweetness was stronger (P<0.05), and overall evaluation was similar acceptance (P<0.05) with ordinarily wheat bread. The obtained results on the extrudate of GBR in this study showed that the extrudate of GBR or the powder would be available for consumer or industrial use as novel food material.

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We established a simple method to identify Bacillus subtilis natto strain KA-145 by PCR. B. subtilis natto is indispensable as a starter strain for fermenting Japanese traditional food "natto". B. subtilis natto strain KA-145 is a recent isolate with high nattokinase activity compared to the normal strain. Discrimination of the bacterial strains is important in controlling contamination of the strains. The IS4Bsu1, a first insertion sequence found in B. subtilis natto, was amplified by PCR, cloned and used for a probe in Southern hybridization. Six to eight copies of IS4Bsu1 were observed in the strains examined and a 1.7kb EcoRV fragment was identified as a marker for the strain KA-145. Inverse PCR technique was used to isolate a 0.3kb sequence adjacent to the IS4Bsu1. Sequence analysis revealed that the IS4Bsu1 sequence was inserted into the multidrug transporter gene, bmr. A bmr gene specific primer pair was constructed to identify the strain KA-145. The PCR based discrimination method is highly specific for detecting the insertion sequence in bmr gene of the strain KA-145 and useful for identifying the strain.

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For efficient industrial production of trehalulose, we conducted an industrialization test using immobilized cells of the high-trehalulose producing bacteria, Pseudomonas mesoacidophila MX-45. Immobilized cells were prepared as follows; cells were concentrated from culture, granulated with calcium alginate, and cross-linked with polyethylenimine and glutaraldehyde. First, we evaluated the useful life of the enzyme. Substrate sucrose solution was continuously fed into a column packed with immobilized cells at 25°C, and the enzyme activity remained stable for 300 days. The enzyme life was longer than that of immobilized cells in industrial palatinose production. Next, we conducted large-scale cultivation of MX-45 in a 2000l culture tank, and obtained culture fluid showing higher enzyme activity than that of the laboratory scale culture. Immobilized cells prepared from the large-scale culture were packed an industrial reactor, and a 40% (w/w) sucrose solution was supplied to the reactor at a flow rate of 3.9t of sucrose per day. In this reaction, approximately 83% of the substrate was converted into trehalulose. These findings suggest that the immobilized cells of MX-45 can be used for efficient industrial production of trehalulose.

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Dried flower of chrysanthemum, Shiranui himekiku, was extracted with phosphate buffered saline (PBS) or ethanol to compare the growth suppressing effect on various cancer cell lines. Both extracts gave a peak at 330nm and the peak was higher in PBS extract than in ethanol extract. When one tenth volume of the PBS extract with various dilutions was added to culture medium of rat liver carcinoma dRLh-84 cells and cultured for 4 days, cell number decrease was observed only in the presence of original extract. On the other hand, the addition of one thousands volume of ethanol extract did not affect the proliferation of the cells. Proliferation of rat normal liver RLN-10 cells was suppressed in the presence of undiluted PBS extract as well as dRLh-84 cells, but the decrease of cell number was not so marked. The PBS extract exerted a strong cytotoxic effect to human liver cancer HuH-7 and HepG2 cells, as well as human mammary cancer MCF-7 cells. On the other hand, it was not cytotoxic, in human lung cancer A549 cells and human leukemia K562 and HL-60 cells. These results suggest that the cytotoxic effect of chrysanthemum flower extract varies with the origin of cancers.

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