Dihydroquercetin
(DHQ), known for its varied physiological benefits,
is widely used in the food, chemical, and pharmaceutical industries.
However, the efficiency of the DHQ synthesis is significantly limited
by the substantial accumulation of intermediates during DHQ biosynthesis.
In this study, DHQ production was achieved by integrating genes from
various organisms into the yeast chromosome for the expression of
flavanone-3-hydroxylase (F3H), flavonoid-3′-hydroxylase, and
cytochrome P450 reductase. A computer-aided protein design approach
led to the development of optimal F3H mutant P221A, resulting in a
1.67-fold increase in DHQ yield from naringenin (NAR) compared with
the control. Subsequently, by analysis of the enzyme reaction and
optimization of the culture medium composition, 637.29 ± 20.35
mg/L DHQ was synthesized from 800 mg/L NAR. This corresponds to a
remarkable conversion rate of 71.26%, one of the highest reported
values for DHQ synthesis from NAR to date.