Aliphatic aldehyde reductase activity related to the formation of volatile alcohols in Vietnamese coriander leaves.

ABSTRACT

Vietnamese coriander (Persicaria odorata Lour.) belongs to a group known as cilantro mimics with the 'cilantro' flavor, in which C10 and C12 aldehydes and alcohols have been found as the potent odor compounds. Their composition isolated by different extraction methods varied. The enzyme activity was assayed, and the reductase acting on some aliphatic aldehydes with NADH/NADPH as a coenzyme was found in a crude enzymatic system of fresh leaves. The maximum activity was observed at pH 8.0 in Na-phosphate and at pH 8.5 to 9.0 in a glycine-NaOH buffer, using heptanal as a substrate. The activated reductase that caused the alcohol generation to increase after a time was inhibited by p-hydroxymercuribenzoate. Our results, which are the first to be reported on Vietnamese coriander leaves, reveal the presence of aliphatic aldehyde dehydrogenase, which is responsible for acid formation, and elucidate the strong activity of the aliphatic aldehyde reductase.