The composition of hot water extract of morus (Morus alba L.) leaves harvested in China were investigated by HPLC system with photo diode array detector. Chlorogenic acid, 1- deoxynojirimycin, rutin, isoquercitrin, astragalin, caffeic acid, quercetin, quercitrin were identified by comparing with authentic samples. Chlorogenic acid was major component and its content was 1.17%. Molus leaves extract showed stronger maltase and sucrase inhibitory activity than α- amylase inhibitory activity. Chlorogenic acid exhibited relatively strong α- amylase inhibitory activity. Chlorogenic acid played an important role in the overall α- amylase inhibitory activity of extract. 1- Deoxynojirimycin showed the strongest maltase and sucrase inhibitor among the compounds tested. Maltase and sucrase inhibitory activity of morus leaves extract depended largely on 1- deoxynojirimycin. Although the clinical value of morus leaves extract needs to be further evaluated, these results suggest that morus leaves extract might be useful for prevention of diabetes.

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Postharvest ripening of pineapple fruit, which is classified as a non-climacteric fruit, was studied from the viewpoint of changes in contents of sugars, organic acids and free amino acids during storage in fruits harvested at different stages of maturity. In immature and mature green fruits, total sugar content (sucrose+fructose+glucose) was not increased, although glucose and fructose contents decreased and sucrose content slightly increased in immature fruit. Total organic acid content (citrate +malate) during on-tree ripening rapidly increased from immature to mature green stage and decreased in ripe fruit to a certain extent, which reflected the change in citrate content. The same pattern of change in organic acid content was observed in immature and mature green fruits during storage. Asparagine, the main free amino acid in pineapple, was accumulated during development, and increased in immature and mature green fruits during storage, similar with the pattern of on-tree change in accordance with the change in organic acid. These results demonstrate that some chemical constituents, organic acids and free amino acids, change even after harvest similarly with the pattern of changes during on-tree ripening, and reconfirmed the characteristics that pineapple fruit partially perform postharvest ripening.

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We investigated decolorization of molasses pigments and production of the viscous substance by cultivation of Mycelia sterilia M 1. Efffective decolorization and increase of viscosity were appeared under molasses concentration of 100g/l in medium. Decolorization and increase of viscosity were promoted by addition of D-glucose and hydrolyzed sucrose by addition of hydrochloric acid. Organic nitrogen in polypepton or yeast extract inhibited decolorizing activity and decreased viscosity. Highest decolorization efficiency and viscosity were obtained at 10 days under the hydrolysis treatment. After removed viscous substance from the culture of M. sterilia M 1, 77.4% of molasses pigments were removed and 91% of sucrose was remained as compaired with preculture medium. The viscous substance was obtained in a yeald of 0.86g per 100ml of culture broth. The viscous substance was assumed to be a kind of polysaccharide which consisted of mainly 6-carbon sugar.

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The antioxidative ability of the dried powder made with the aqueous extract from roots of arrowroot or that leaves, was examined in a powder system at water activity (Aw) 0.2-1.0 and 50 °C. The cookie was prepared by baking the dough, composed of the dried powder, soft flour, linoleic acid, baking powder and water in the ratio of 8.5 : 25.0 : 8.5 : 1.0 : 12.0 by weight. In the case of preparing the control one, the dried powder was changed for soft flour. Although the peaks of Peroxide values (PV) were shown at the all Aw range in the control sample (cellulose powder) by the fourth day after beginning incubation, such peaks weren't obtained in the dried powders mentioned above without the PV in the 50% root extract at Aw 0.2. The antioxidative ability of cookies added with each of dried powder from roots of arrowroot or that leaves was strong at Aw0.6-1.0.

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