Isoquercitrin is a rare flavonol glycoside with a wide range of biological
activities and is a key synthetic intermediate for the production of
enzymatically modified isoquercitrin. In order to establish an ultrafast
bioprocess for obtaining isoquercitrin, a novel continuous flow biosynthesis
of isoquercitrin using the hesperidinase-catalyzed hydrolysis of rutin in a
glass-polydimethylsiloxane (PDMS) microreactor was first carried out. Using
the developed microchannel reactor (200?m width, 50?m depth, and 2 m
length) with one T-shaped inlet and one outlet, the maximum yield of
isoquercitrin (98.6%) was achieved in a short time (40 min) under the
following optimum conditions: rutin concentration at 1 g L-1, hesperidinase
concentration at 0.1 g mL-1, reaction temperature at 40?C, and a flow rate
at 2 ?L min-1. The activation energy value Ea of the enzymatic reaction was
4.61 kJ mol-1, and the reaction rate and volumetric productivity were
approximately 16.1-fold and 30% higher, respectively, than those in the
batch reactor. Thus, the use of a continuous-flow microreactor for the
enzymatic hydrolysis of rutin is an efficient and simple approach to achieve
a relative high yield of isoquercitrin.
Ultrafast synthesis of isoquercitrin by enzymatic hydrolysis of rutin in a continuous-flow microreactor