著者

Hiroshi TAKII Takashi KOMETANI Takahisa NISHIMURA Takashi KURIKI Tohru FUSHIKI

出版者

Japanese Society for Food Science and Technology

雑誌

Food Science and Technology Research (ISSN:13446606)

巻号頁・発行日

vol.10, no.4, pp.428-431, 2007-11-25 (Released:2008-08-28)

参考文献数

18

被引用文献数

20 23

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Gastrointestinal disorders after ingesting a sports drink were investigated during bicycle exercise. The experiment consisted of a preliminary exercise, a 10 min rest, and 30 min of exercise. Seven healthy untrained volunteers ingested either water or a sports drink based on highly branched cyclic dextrin (HBCD), commercially available dextrin of DE16 or glucose immediately after the preliminary exercise. The mean gastric emptying time after ingestion of the HBCD-based sports drink was significantly faster than that of the glucose-based drink. Gastrointestinal disorders were monitored by a questionnaire. The mean degree of subjective flatulence and the mean number of belches were few with the HBCD-based drink during exercise. When volunteers drank the sports drink based on 10% HBCD during bicycle exercise, they experienced few gastrointestinal disorders and consequently could continue the exercise comfortably with little fatigue.

著者

Kazuhisa Sugimoto Takahisa Nishimura Takashi Kuriki

出版者

FCCA(Forum: Carbohydrates Coming of Age)

雑誌

Trends in Glycoscience and Glycotechnology (ISSN:09157352)

巻号頁・発行日

vol.19, no.110, pp.235-246, 2007-11-02 (Released:2008-12-12)

参考文献数

38

被引用文献数

5 10

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私たちはフェノール性水酸基への糖転移反応を効率的に触媒する新規酵素を得ることに成功した。本酵素、すなわちハイドロキノン配糖化酵素はα-アノマー選択的な配糖化反応を触媒した。さらに本酵素を用いる反応は、生成物である4-hydroxyphenyl-O-α-D-glucopyranosideを非常に高い収量で得ることができ、産業的な利用に十分なレベルを充たしていた。本酵素反応によりコウジ酸やカフェ酸をはじめ多くのフェノール化合物が配糖化されたがアルコールは配糖化されなかった。さらに私たちは本酵素反応により得られた配糖体の一種である4-hydroxyphenyl-O-α-D-glucopyranoside (α-アルブチン) の応用研究に取り組んだ。α-アルブチンはヒト細胞由来チロシナーゼを強力に阻害し、その阻害活性は構造異性体である4-hydroxyphenyl-O-α-D-glucopyranoside (アルブチン) よりも非常に高いものであった。私たちは数種類のα-アルブチン配糖体とアルブチン配糖体を酵素合成した。得られた配糖体のチロシナーゼ阻害活性の比較結果から、分子の大きさとベンゼン環周辺の静電ポテンシャルがハイドロキノン配糖体のヒトチロシナーゼ阻害作用に大きく影響を与えることが示唆された。さらにα-アルブチンのメラニン生合成に対する阻害効果についても検討を行った。α-アルブチンは細胞毒性を示さない濃度域においてヒトメラノーマ細胞やヒト皮膚3次元モデルのメラニン生成を濃度依存的に抑制した。上記の結果よりα-アルブチンは有効かつ安全な化粧品用美白素材であることが示唆された。

著者

Kazuhisa Sugimoto Takahisa Nishimura Koji Nomura Kenji Sugimoto Takashi Kuriki

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.51, no.7, pp.798-801, 2003 (Released:2003-07-01)

参考文献数

16

被引用文献数

103 110

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The effects of 4-hydroxyphenyl α-glucopyranoside (α-arbutin) and 4-hydroxyphenyl β-glucopyranoside (arbutin) on the activity of tyrosinase from human malignant melanoma cells were examined. The inhibitory effect of α-arbutin on human tyrosinase was stronger than that of arbutin. The Ki value for α-arbutin was calculated to be 1/20 that for arbutin. We then synthesized arbutin-α-glycosides by the transglycosylation reaction of cyclomaltodextrin glucanotransferase using arbutin and starch, respectively, as acceptor and donor molecules. The structural analyses using 13C- and 1H-NMR proved that the transglycosylated products were 4-hydroxyphenyl β-maltoside (β-Ab-α-G1) and 4-hydroxyphenyl β-maltotrioside (β-Ab-α-G2). These arbutin-α-glycosides exhibited competitive type inhibition on human tyrosinase, and their Ki values were calculated to be 0.7 mM and 0.9 mM, respectively. These arbutin-α-glycosides posessed stronger inhibitory activity than arbutin, but less activity than α-arbutin. These results suggested that the α-glucosidic linkage of hydroquinone-glycosides plays an important role in the inhibitory effect on human tyrosinase.