Directional biocatalytic production of high titer hydroxyl acid by the
intensified regulation on biocatalysis
Abstract
Hydroxyl acid has become an important chemical in the field of materials
and medicine due to its dual functional modules. Fortunately,
Gluconobacter oxydans whole-cell catalysis is on spotlight with
promising potential in bio-catalyzing polyhydroxy chemical to produce
hydroxyl acids. Therefore, straight-chain primary diols (C2-C6) were
investigated as substrates oxidized by G. oxydans. As results, we found
a fantastic critical point of methylene-number determining end-products.
G. oxydans catalyzes C4 and smaller methylene-number compounds only
forming hydroxyl acids, but C5/C6 can be converted to diacids.
Furthermore, it was important that we successfully selective and
directionality controlled the product of C5/C6 primary diols to hydroxyl
acids instead of diacids through the regulation of pH≥5.5. Finally, we
successfully produced nearly 102.3 g/L 5‑hydroxyvaleric acid during 48 h
with 99.8% yield by sealed-oxygen supply (SOS) biotechnology which is
the highest level. These findings have important reference significance
for the selective and directionality bioconversion of primary diols into
hydroxyl acids and provide a promising path for the industrial
development of hydroxyl acids with integrating C2-C6.