Elimination of aldoses as an aniline derivative in enzymatic transgalactosylation of lactose is described. This was performed in the presence of ketose or non-reducing sugar as the acceptor to isolate non-reducing- or keto-oligosaccharides. Aldoses were eliminated quantitatively as an aniline derivative by extraction with organic solvent and by subsequent treatment with activated charcoal and cation exchange resin. Non-reducing- or keto-oligosaccharides which did not react with aniline were separated from transgalactosylation products.

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The aroma constituents of Goishi-cha and Awa-cha manufactured by a pickling process similar to that for Miang, Niang and Letpet of Southeast Asia were analyzed by GC-MS. The aroma concentrates from both our tea samples showed a characteristic pickling flavor. Their aroma bases were: (Z)-3-hexenol, linalool and its oxides, methyl salicylate, benzyl alcohol, 2-phenylethanol, acetic acid and 4-ethylphenol. They were similar to those of fermented tea. Goishi-cha contained much more microbial metabolites and had a higher characteristic pickling aroma than Awa-cha. Through this analysis, 12 compounds were newly identified in the tea aroma: methyl lactate, acetoin, 2-methyl-1-penten-3-ol, 3-methyl-2-buten-1-ol, 2-heptanol, 3-octanol, (E)-2-octenol, 4-methylguaiacol, 1, 2, 3-trimethoxybenzene, 4-ethylphenol, 2, 6-dimethoxyphenol and methyl 11-hexadecenoate. They were shown to be microbial metabolites and to have a fermentative flavor and moldy odor. The degraded products of carotinoids by solar-drying were larger in Awa-cha than in Goishi-cha, and they seem to contribute to the withered leaf aroma of Awa-cha.

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The formation of 3, 7-dimethyl-1, 5, 7-octatriene-3-ol (trieol) was investigated in aroma concentrates of various grades of green tea at different heating temperatures by GC and GC-MS analysis.
Small amounts of trienol formed at 110_??_120°C, large amounts at 130_??_140°C, but none at below 100°C. The amount of trienol formed by heating was highest in Bancha (the lowest grade, made from coarse leaves and stalks), especially in stalks, lessened with higher tea grades and was lowest in high grade tea.
A dienediol component was isolated from the aroma concentrate of stalks of bancha, and retention times in GC and mass spectrum were identical with those of authentic 3, 7-dimethyl-1, 5-octadiene-3, 7-diol (dienediol). As the trienol is produced in vitro from the dienediol by dehydration at 120_??_130°C, it was presumed that the trienol in green tea was also produced from dienediol by dehydration during the heating process.

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The water in which fruits or vegetables are soaked is often used in traditional recipes of “Mantou” fermentation in China. It is already known that wild yeasts play an important role in leavening. The study have reports on the successful isolation of the sole microorganism in the water of soaked apple slices. The isolate was identified as Enterobacter cloacae. It was confirmed that this strain aided in Mantou-leavening.

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Fucose-containing sulfated polysaccharide (SPS) fractions were prepared from 85% methanol-treated materials of nine different species of brown seaweeds. They were extracted with diluted hydrochloric acid (pH 2) at room temperature and the extracts fractionated with aqueous 3% cetylpyridinum chloride and 2% CaCl₂ solutions. Electrophoresis indicated that each of the obtained fractions consisted of more than two polymeric components. Chemical analysis and g. l. c. showed that each SPS fraction contained fucose, galactose, mannose, xylose, glucuronic acid and half ester sulfate as constituents. The proportions of the constituents varied widely from one fraction to another.
Blood-anticoagulant activity tests were conducted on each SPS fraction with human or sheep plasma. The tests included thrombin time (TT), activated partial thromboplastin time (APTT), and anti-(factor Xa) activity in comparison with values of heparin (167 units/mg). When assayed for human plasma, all SPS fractions showed some TT(0-35 units/mg) and APTT (12-38 units/mg) activities, whereas anti-(factor Xa) activity was not remakable in any SPS fraction. Among the SPS fractions tested, that of Ecklonia kurome exhibited the highest activity with respect to TT (35 units/mg) and APTT (38 units/mg). When assayed for sheep plasma, the fraction of E. kurome showed higher activity than that determined for human plasma (activity with respect to TT and APTT was 120 and 95 units/mg).

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The caffeine content of various kinds of tea was quantitatively analyzed by the HPLC method. Water and total nitrogen contents were also analyzed and compared with caffeine content in small leaf species (var. sinensis) and large leaf species (var. assamica). The correlation coefficient between dried-caffeine and dried-total nitrogen was 0.93 in small species and 0.92 in large species and the linear one-dimensional regression formula was y=0.47 x+0.77, and y=1.07 x-0.77, respectively. The ratio between caffeine content and total nitrogen content was larger in var. assamica than in var. sinensis. However, both of these tea varieties produced from wild plants, for example Miang, Goishi-cha and Awa-cha, showed very similar values for caffeine and total nitrogen content. Therefore, these results may provide a clue to the origin of the tea plants.

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[in Japanese]

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