L-Ascorbic Acid의 생체분해

A Possible Enzymatic Catabolism of L-Ascorbic Acid via $\alpha$-Ketoaldehydes

L-Ascorbic aciddm ltodcp 산화분해과정중 ${\alpha}$-ketoaldehyde의 한 종류인 3,4,5-trihydroxy-2-keto-L-valeral-dehyde(L-xylosone)가 형성된다는 사실을 핵자기공명스펙트럼분석법으로 확인하였다. 이 물질은 glyoxalase system에 의해 L-xylonic acid로 변환되고 계속해서 L-erythroascorbic acid로 산화된다. 이러한 근거 위에서 vitamin C의 분해과정이 vitamic C 이외의 두종류의 ${\gamma}$-lactones-과 3종류의 ${\alpha}$-ketoaldehydes로 구성된 분해경로를 갖는다는 사실을 제안하였다.

It is shown by means of nuclear magnetic resonance spectroscopy that 3,4,5-trihydroxy-2-keto-L-valeraldehyde (L-xylosone), an ${\alpha}$-ketoaldehyde, is formed during the oxidative catabolism of L-ascorbic acid. It is proposed that this substance serves as a substrate for the glyoxalase system by which it is transformed to L-xylonic acid. As L-xylonic acid is further oxidized to L-erythroascorbic acid, a biochemical pathway is proposed for the action of vitamin C which consists of two further ${\gamma}$-lactones and three different substrates of the glyoxalase system.