A NIR spectral imaging apparatus was developed to obtain information on spectrally discriminated images and the location of material to be measured. The apparatus consisted mainly of a CCD camera, a liquid crystal tunable filter and a spectral illuminator, which consisted of a xenon lump as well as a grating spectrometer. The sample surface image could be captured at any wavelength from 400nm to 1100nm. To investigate the performance of the apparatus, it was employed in the measurement of sugar content distribution at the surface of a fresh green melon cut in half and in the detection of foreign materials among blueberries. The absorbance at 676nm was found to be highly correlated with the sugar content in fresh green melons. Next, the intensity of each pixel of the images was converted into sugar content. By assigning the sugar content to a linear color scale, the sugar distribution of the melon was visualized. The plant organs could be detected by the second derivative absorbance image at 680nm, which is an absorption band of chlorophyll. The second derivative absorbances for blueberries and plant organs were determined in the image. The positions of pixels judged as plant organs in the detection image were in good agreement with the actual locations where plant organs had been placed. The apparatus demonstrated that plant organs contaminating the raw blueberry materials could be detected using the proposed methodologies.

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[in Japanese]

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Antioxidant activities of young sesame leaves (Sesamum indicum L.) were measured using 3 different radical scavenging methods (DPPH, ABTS, and superoxide anion radicals). The activities of young sesame leaves in any of the methods were higher than those of barley and kale, while mulberry leaves had the highest activity. The activities were dependent on the polyphenol content in samples (mulberry, 15.9 ; sesame, 9.39 ; kale, 3.61 ; barley, 2.04mg-gallic acid equivalent/g-dry weight). However, when antioxidant activities per weight of polyphenol were estimated, the young sesame leaves showed the same or higher antioxidant activity than mulberry leaves, suggesting that young sesame leaves would contain strong antioxidative phenolic compounds. Next, when young sesame leaf extract was applied to an HPLC-DPPH online post-column system, nine peaks (S1∼S9) appeared in the UV chromatogram at 340nm, and HPLC-separated components corresponding to peaks S4, S5, S6 and S8 reacted with DPPH. This result suggests that these are the major antioxidative components in young sesame leaves. From the results of several chromatographic purifications, about 1.4kg of young sesame leaf powder yielded 524mg of compound S5. The MS and NMR analyses revealed that S5 was acteoside, a phenylpropanoid glycoside. The acteoside content in young sesame leaf powder was 1.2%.

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Glycemic index (GI) determination requires dozens of capillary blood samplings by fingertip puncture, resulting in patient discomfort. Therefore, a new method without painful capillary blood samplings is highly desirable. In this study, a non-invasive blood glucose sensor using short-wavelength near-infrared (NIR) spectroscopy was developed and its application to glycemic index determination was examined. A non-invasive blood glucose sensor was developed based on the existing spectrophotometer with fiber optics in interactance mode. In order to avoid spectral variation, measuring area, contact pressure and sample temperature were kept constant. NIR spectra in the short-wavelength region from 700nm to 1050nm were measured on the palm of the hand during standard food tolerance tests as part of GI determination. Partial least squares (PLS) regression was employed to derive an individual calibration model for determining blood glucose content. The standard error of cross-validation (SECV) for the developed calibration model was 9.1mg/dL. The GIs of three test foods, white rice, boiled fish paste and yogurt, calculated using the blood glucose values measured by the developed calibration model, were 70 (calculated using actual values=80), 57 (49), and 45 (38), respectively. The non-invasive blood glucose sensor using short-wavelength NIR spectroscopy shows promise for its applicability to GI determination.

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Detailed investigations of the contents of antioxidant substances, such as carotenoids and polyphenols, in traditional Okinawan vegetables have not been conducted. In this study, we determined αand β-carotene, lutein, chlorophyll, and polyphenol contents in traditional Okinawan vegetables. We compared several simultaneous extraction methods for carotenoids, chlorophylls, and polyphenols from vegetables, and concluded that the accelerated solvent extraction (ASE) system using 80% ethanol solution is the best method for the extraction of such compounds. The extract obtained by ASE was analyzed for carotenoids and chlorophylls using HPLC and for polyphenols using the Folin-Ciocalteu method. Among the vegetables that we analyzed, Nishiyomogi, Botanbouhuu, Hosobawadan, and Suizenjina revealed high β-carotene content. Moreover, Botanbouhuu was not only rich in β-carotene (5029±629μg/100g fresh weight), but also lutein (8.2±1.3mg/100g fresh weight), total polyphenols (251.3±23.4mg/100g fresh weight), and vitamin C (45.8±15.4μg/100g fresh weight). Thus, the present study revealed that Botanbouhuu is richer in various antioxidant substances than the other analyzed vegetables.

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Recently, the number of elderly with aspiration pneumonia has increased. Improvement of the oral microbiota is thought to be important for the prevention of aspiration pneumonia. For example, the ratio of oral bacteria can be increased by selective pressure. Therefore, we investigated the effect of several food components on the multiplication of oral bacteria and pathogenic bacteria in an in vitro study. A 15μg/ml (−)-epigallocatechin gallate (EGCg) solution reduced the growth rates of oral bacteria (S. mitis, S. oralis, S. salivarius) by about 50%, while it did not suppress the growth rates of S. pneumoniae, S. sanguinis, S. mutans, E. faecium, P. aeruginosa and E. coli. A 10mg/ml xylitol solution decreased the growth rates of Streptococcus species by about 50%. However, the growth rates of Gram-negative species could not be suppressed by the solution. A 5mg/ml caffeine solution reduced growth rates of the oral bacteria by about 50% and the growth rates of the pathogenic bacteria were more suppressed than those of the oral bacteria.

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Royal jelly (RJ) has many biologically active ingredients : protein, sugar, lipid (e.g., 10-hydroxy-2-decenoic acid) and other chemicals. Apisin is a 350-kDa glycoprotein, which is the main protein component of RJ. We isolated and purified apisin from fresh RJ through a series of operations, i.e., dialysis, centrifuge separation and ion exchange column chromatography. We investigated whether RJ and purified apisin promote cell proliferation and the production of collagen in normal human neonatal skin fibroblasts, NB1RGB cells. Moreover, we investigated whether apisin promotes the differentiation of MC3T3-E1, a mouse osteoblastic cell line with calcium and hydroxyapatite production. RJ and apisin induced proliferation and collagen production in NB1RGB cells, and promoted the differentiation of MC3T3-E1 into osteoblasts. These findings suggest that RJ has proliferationand differentiation-inducing functions, and these effects may be partly mediated via the effects of apisin.

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Adhesion inhibition and antibacterial activities of 13 kitchen detergents were determined against S. Enteritidis IFO3313, P. aeruginosa NBRC 13275, P. fluorescens No. 3 and L. monocytogenes No. 185. All the detergents tested inhibited the adhesion of S. Enteritidis IFO 3313 to microplates more than 50% at 0.025% (W/V), without a decrease in viable counts. Adhesion of P. fluorescens No. 3 was inhibited more than 50% by 2 detergents even at 0.0025% (W/V). Four detergents completely inhibited the adhesion of tested bacteria, except for P. aeruginosa NBRC 13275, at a concentration lower than that recommended for washing vegetables. Adhesion inhibition activity appears higher in detergents containing linear alkylbenzenesulfonates and polyoxy ethylene alkyl ether sulfonates but not alkylamine oxides.

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We examined the effects of high temperatureand pressure-treated garlic (HTPG), which has enhanced antioxidative activity, on 1,2-dimethylhydrazine (DMH)-induced mucin-depleted foci (MDF), as premalignant lesions, in the rat colorectum at the post-initiation stage. Male F344 rats (5 weeks old) were injected s.c. with DMH (40mg/kg, once weekly for 2 weeks). Rats were fed basal diet or experimental diets containing 1% or 3% HTPG for 6 weeks, starting 1 week after the last injection of DMH. At sacrifice, the number of MDF in the 3% HTPG diet group was significantly lower than that in the basal diet group. In addition, we also studied the influence of 3% HTPG diet ingestion. Rats were fed basal diet or 3% HTPG diet under the above conditions without DMH treatment. The 3% HTPG diet did not affect most hematological and plasma biochemical parameters. These results, combined with our previous work (APJCP, 2009), suggest that HTPG may be useful as a health supplement.

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[in Japanese]

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