title: 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: 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.
authors.affiliation: Research Institute for Medicines and Pharmaceutical Sciences (i-Med-UL), Faculty of Pharmacy, University of Lisbon, Avenue Prof. Gama Pinto, 1649-003 Lisbon, Portugal.
authors.forename: Hélder
authors.initials: H
authors.lastname: Vila-Real
authors.forename: António J
authors.initials: AJ
authors.lastname: Alfaia
authors.forename: M Rosário
authors.initials: MR
authors.lastname: Bronze
authors.forename: António R T
authors.initials: AR
authors.lastname: Calado
authors.forename: Maria H L
authors.initials: MH
authors.lastname: Ribeiro