水分化指数 - - 氷の再結晶化の阻害における小分子水分化を説明するためのより良いパラメータです

Roger Y Tam¹, Sandra S Ferreira, Pawel Czechura

¹Department of Chemistry, D'Iorio Hall, 10 Marie Curie, University of Ottawa, Ottawa, Ontario, Canada, K1N 6N5.

Journal of the American Chemical Society

|December 5, 2008

まとめ

D-ガラクトーゼやD-メリビオゼのような単純な砂糖は,氷の再結晶化を効果的に阻害します. 新しい"水分化指数"は,結合した水と分子サイズに基づいて,この氷再結晶化 (RI) 活動を正確に予測します.

科学分野:

バイオケミストリーバイオケミストリー
物理化学物理化学
材料科学材料科学とは

背景:

氷の再結晶化 (RI) は,小さな氷の結晶がより大きな結晶に溶け,凍った材料に影響を与えるプロセスです.
RIを阻害する分子を理解することは,冷凍保存と食品科学にとって極めて重要です.
炭水化物は,潜在的RI阻害特性のために調査されています.

研究の目的:

氷の再結晶阻害 (RI) 活性を評価するために,様々なモノおよびディサカライド.
炭水化物の水分化特性とRI活性を相関させるため.
炭水化物によるRI阻害の予測モデルを開発する.

主な方法:

いくつかの単糖および二糖質のRI活性がテストされました.
文献で報告された水分化数と計算されたモール体積と相関するRI活動.
RI活動の予測のための新しい"水分化指数"を定義し,検証しました.
RI活動に対する炭水化物濃度の影響を調査した.

主要な成果:

D-ガラクトーゼとD-メリビオゼは強力なRI阻害剤として特定されました.
絶対的水分濃度値はRI活性を正確に予測できませんでした.
新しい水分化指数は,実験的なRI活動と強い相関関係を示した.
RI活動に対する炭水化物濃度の影響は非連結的であった.

結論:

水分化指数は,炭水化物媒介による氷再結晶抑制の信頼できる予測指標である.
炭水化物は,氷水界面の水構造を乱すことで,RIを阻害する.
RI抑制のためのC結合炭水化物誘導体に関するさらなる研究が必要である.

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