Determination of rutin, catechin, epicatechin, and epicatechin gallate in buckwheat Fagopyrum esculentum Moench by micro-high-performance liquid chromatography with electrochemical detection.
A simple and sensitive method has been developed for determining rutin, catechin, epicatechin, and epicatechin gallate in buckwheat (Fagopyrum esculentum Moench) flour and seeds by micro-high-performance liquid chromatography with electrochemical detection. Chromatography was performed using an octadecylsilica column, acetonitrile-water-formic acid (13:87:1, v/v/v) as a mobile phase, and an applied potential at +0.5 V vs Ag/AgCl. We found that Japanese buckwheat flour contains rutin (12.7 mg/100 g), catechin (3.30 mg/100 g), epicatechin (20.5 mg/100 g), and epicatechin gallate (1.27 mg/100 g). The relative standard deviations for rutin, catechin, epicatechin, and epicatechin gallate peak heights were less than 0.86% (n = 5). The detection limit of rutin was 0.86 ng/mL. Moreover, the present method was applied to the distribution analysis of these compounds in buckwheat seed. The embryo proper and cotyledons of a mature buckwheat seed contained rutin with the highest concentration as compared to other parts. This method is useful in determining rutin, catechin, epicatechin, and epicatechin gallate in buckwheat with a small amount of sample for quality control in the food industry.
Danila
Ana-Maria
AM
Department of Analytical Chemistry, Faculty of Pharmacy, University of Medicine and Pharmacy Gr.T. Popa, Iasi, Romania.
Kotani
Akira
A
Hakamata
Hideki
H
Kusu
Fumiyo
F
D000975:Antioxidants / Q000032:analysis; D002392:Catechin / Q000031:analogs & derivatives* / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004563:Electrochemistry; D019612:Fagopyrum / Q000737:chemistry*; D012431:Rutin / Q000032:analysis*
D000975:Antioxidants; D012431:Rutin; D002392:Catechin; C062669:epicatechin gallate