Enzymatic Synthesis of the Flavone Glucosides, Prunin and Isoquercetin, and the Aglycones, Naringenin and Quercetin, with Selective α-L-Rhamnosidase and β-D-Glucosidase Activities of Naringinase

Abstract EN

The production of flavonoid glycosides by removing rhamnose from rutinosides can be accomplished through enzymatic catalysis.

Naringinase is an enzyme complex, expressing both α-L-rhamnosidase and β-D-glucosidase activities, with application in glycosides hydrolysis.

To produce monoglycosylated flavonoids with naringinase, the expression of β-D-glucosidase activity is not desirable leading to the need of expensive methods for α-L-rhamnosidase purification.

Therefore, the main purpose of this study was the inactivation of β-D-glucosidase activity expressed by naringinase keeping α-L-rhamnosidase with a high retention activity.

Response surface methodology (RSM) was used to evaluate the effects of temperature and pH on β-D-glucosidase inactivation.

A selective inactivation of β-D-glucosidase activity of naringinase was achieved at 81.5∘C and pH 3.9, keeping a very high residual activity of α-L-rhamnosidase (78%).

This was a crucial achievement towards an easy and cheap production method of very expensive flavonoids, like prunin and isoquercetin starting from naringin and rutin, respectively.