Large-scale extraction of polyphenolics from sweet potato tops was analyzed for its applicability in industry. The sweet potato cultivar “Koganesengan” was chosen because its tops generate the majority of its sweetness during Shochu brewing and starch production. The yield of the hot-water extract at 95°C was 219g (dry weight) from 100kg (fresh weight) of sweet potato tops, giving a 34.1% recovery of polyphenolics from the dried powder. The extract was composed of 49.9% caffeoylquinic acid (CQA) derivatives. HPLC analysis revealed three mono CQAs (3-, 4-, and 5-CQAs), three diCQAs (3,4-, 3,5-, and 4,5-diCQAs), and 3,4,5-triCQA. The 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity of the extract was 75.2% that of commercial chlorogenic acid.

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To extract the major allergen (Pru p3) from peach skin, a small-scale method was developed. This method involves shaking a small amount of peach skin on a high speed shaker instead of homogenizing it. Protein was extracted in sufficient quantity by shaking 5g of skin from one peach in a buffer solution (pH 5) containing 20mmol/L ascorbic acid sodium salt. Total RNA was extracted from mature peach skin by the SDS-phenol method to obtain high concentration mRNA. Following purification of total RNA using a commercial kit, cDNA was amplified by RT-PCR using mRNA and oligo dT primers. Pru p3 expression in peach was confirmed by nested PCR using cDNA templates.

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Agaro-oligosaccharides (AGOs) are easily produced from agar under acidic conditions. We previously reported inhibitory action of AGOs on the production of pro-inflammatory mediators, such as nitric oxide, prostaglandin E₂, pro-inflammatory cytokines, in LPS-stimulated monocyte/macrophages. This inhibitory activity is thought to result from the induction of heme oxygenase-1 (HO-1). Here, we further clarified the induction mechanism of HO-1 and its involvement in the anti-inflammatory activity of AGOs. HO-1 expression is known to be regulated by the transcription factor, nuclear factor E2-related factor-2. We verified that siRNA of this transcription factor could attenuate the induction of HO-1 by AGOs. The production of some pro-inflammatory mediators has been associated with mitogenic stimuli (i.e., LPS), followed by activation of transcription factor, nuclear factor-kappa B. We found that AGOs partially suppressed LPS-mediated nuclear factor-kappa B activation, whereas HO-1 siRNA showed no effect on this inhibitory activity. Taken together, AGOs appear to exert their anti-inflammatory effects on activated macrophages through both HO-1-dependent and -independent mechanisms.

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This study attempted to clarify the safety of excessive intake (400mg) of calcium-fortified fish sausage, a special health food in Japan, in the prevention of osteoporosis. Safety was evaluated based on an open-label human trial in which 20 healthy subjects took 3 times the recommend amount of fish sausages a day for 4 weeks. Adverse events were assessed, and physical measurements, laboratory assessment and nutrition were analyzed. During the 4-week safety evaluation, no clinical changes were found in any of the subjects. Thus the daily intake of fish sausage appears to be safe as a means to obtain the daily requirements of calcium.

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To clarify the aroma characteristics of fermented tea manufactured by mixed kneading of the third crop of green tea leaves and loquat leaves (mixed fermented tea), we measured the aroma components by gas chromatography/mass spectroscopy. (Z)-3-hexen-1-ol acetate, which was not a component found in green or loquat tea, was detected in the mixed fermented tea. Geraniol was the most abundant aroma component in the mixed fermented tea. A relatively large amount of benzaldehyde, benzylalcohol and nerolidol was detected in the mixed fermented tea compared to that in black, green and loquat teas. These results suggest that the aroma components of the mixed fermented tea were produced during fermentation after the mixture of green tea and loquat leaves.

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Soy protein has hypolipidemic action on blood and liver. We thus manufactured lactic fermented food from soymilk and investigated the physiologically effective dosage of fermented soymilk. Male Sprague-Dawley rats were fed a soy protein-free diet (control), or a diet containing 12.5% (soy protein 5%) or 25.0% (soy protein 10%) fermented soymilk. Rats fed the soy protein diets showed significant suppression of hepatic lipids and total cholesterol level in plasma, as well as a tendency in the decrease of visceral fat. These effects depended on the amount of fermented soymilk supplemented in the diet. Supplementation of more than 10% fermented soymilk was necessary to achieve significant physiological effects.

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