Fungal Metabolism of Sorbic Acid

Abstract

The metabolism of sorbic acid (SA) by 11 species of Mucor and 14 other fungi in addition to Mucor sp. A-73 were studied. All species of Mucor metabolized SA to trans-4-hexenol (4-HEL) without exception. The metabolic pathway was investigated precisely by using the resting cells of Mucor sp. A-73. The reduction of SA to 4-HEL by the fungus demanded glucose. The reduction of SA to sorbic alcohol (SAL) was catalyzed by the inducible enzymic system and that of SAL to 4-HEL by the constitutive enzyme. In the phosphate buffer, a part of 4-HEL produced from SA was further transformed into mono-trans-4-hexenyl phosphate by Mucor sp. A-73.
The reductive action of the fungus upon several trans-2-alkenoic acids was also examined.