Determination of Riboflavin in Teaby High-Performance LiquidChromatography

Abstract

A HPLC method for riboflavin determina-tion in tea was developed. An assay solu-tion was prepared as follows: 2g of tea wasextracted with 40ml of 0.1 N HC1 in boilingwater for 30min. The extract was incubatedat 48°C for 3h after addition of 5ml of 1MNaOAc and 5ml of 6% taka-diastase, thencentrifuged at 3000rpm for 10min. Thesupernatant was filtered using a 0.45μmfilter, and 90μl of the filtrate was subjected to HPLC. The HPLC system consisted of aODS-120A (4.6mm_φ×25cm) column, a sol-vent system of H2O-CH3CN-ACOH (88.5:11:0.5) and a flow rate of 1.0ml/min. Quantity of riboflavin was based on fluorescence, excitation at 360nm, and emission at 500nm. The riboflavin recovery was 96.2%.