Biochemical synthesis of the medicinal sugar l-gulose using fungal alditol oxidase.

Some rare sugars can be potently medicinal, such as l-gulose. In this study, we present a novel alditol oxidase (fAldOx) from the soil fungus Penicillium sp. KU-1, and its application for the effective production of l-gulose. To the best of our knowledge, this is the first report of a successful direct conversion of d-sorbitol to l-gulose. We further purified it to homogeneity with a ∼108-fold purification and an overall yield of 3.26%, and also determined the effectors of fAldOx. The enzyme possessed broad substrate specificity for alditols such as erythritol (kcat/KM, 355 m-1 s-1), thus implying that the effective production of multiple rare sugars for medicinal applications may be possible.

Efficient production of the rare sugar l-gulose using a wheat-bran culture extract of Penicillium sp. KU-1.

We found that l-gulose, a rare sugar, was produced from d-sorbitol efficiently, using a wheat-bran culture extract of the fungus Penicillium sp. KU-1 isolated from soil. The culture extract showed enzyme activity for the oxidation of d-sorbitol to produce l-gulose; a high production yield of approximately 94% was achieved.