title: Screening and quantification of the enzymatic deglycosylation of the plant flavonoid rutin by UV-visible spectrometry.
abstract: The enzymatic deglycosylation of the plant flavonoid rutin (quercetin-3-O-(6-O-α-l-rhamnopyranosyl-β-d-glucopyranoside) is usually assessed by means of high performance liquid chromatography (HPLC). We have developed a spectrophotometric method for the quantification of the released quercetin. After the enzymatic reaction, quercetin is extracted with ethyl acetate, and subsequently oxidized under basic conditions. The absorbance of quercetin autooxidation products at 320nm was correlated with the quercetin concentration by linear regression (molar extinction coefficient 23.2 (±0.3)×103M-1cm-1). With this method, rutin-deglycosylation activity in buckwheat flour and a commercial naringinase was measured, and showed no significant differences with the results obtained by HPLC. The convenience of this method resides on the enzymatic activity quantification using the natural substrate by UV-visible spectrometry. Moreover, the simplicity and speed of analysis allows its application for a large number of samples.
authors.affiliation: INCITAP UNLPam-CONICET, Instituto de Ciencias de la Tierra y Ambientales de La Pampa, Departamento de Química, FCEyN, Universidad Nacional de La Pampa (UNLPam), Av. Uruguay 151, (6300) Santa Rosa, La Pampa, Argentina.
authors.forename: Gisela
authors.initials: G
authors.lastname: Weiz
authors.affiliation: INCITAP UNLPam-CONICET, Instituto de Ciencias de la Tierra y Ambientales de La Pampa, Departamento de Química, FCEyN, Universidad Nacional de La Pampa (UNLPam), Av. Uruguay 151, (6300) Santa Rosa, La Pampa, Argentina.
authors.forename: Javier D
authors.initials: JD
authors.lastname: Breccia
authors.affiliation: INCITAP UNLPam-CONICET, Instituto de Ciencias de la Tierra y Ambientales de La Pampa, Departamento de Química, FCEyN, Universidad Nacional de La Pampa (UNLPam), Av. Uruguay 151, (6300) Santa Rosa, La Pampa, Argentina. Electronic address: mazzaferrolaura@gmail.com.
authors.forename: Laura S
authors.initials: LS
authors.lastname: Mazzaferro
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005419:Flavonoids / Q000032:analysis / Q000737:chemistry*; D009097:Multienzyme Complexes / Q000737:chemistry*; D012431:Rutin / Q000032:analysis / Q000737:chemistry*; D013053:Spectrophotometry / Q000379:methods*; D014466:Ultraviolet Rays; D001617:beta-Glucosidase / Q000737:chemistry*
chemical_list: D005419:Flavonoids; D009097:Multienzyme Complexes; D012431:Rutin; C039827:naringinase; D001617:beta-Glucosidase
keywords: Naringinase; Rutin-degrading enzymes; α-l-Rhamnosidase; β-d-Glucosidase