High Performance Liquid Chromatographic Determination of Anthocyanin Pigments in Some Varieties of Black Rice
SU NOH RYU1, SUN ZIK PARK2 AND CHI-TANG HO3*
1. National Crop Experiment Station, Rural Development Administration, Suwon, Kyeongki-Do, 441-100, Republic of Korea
2. Department of Agricultural Science, Korea National Open University, Seoul, 110-791, Republic of Korea
3. Department of Food Science, Cook College, Rutgers, The State University of New Jersey, 65 Dudley Road, New Brunswick, NJ 08901-8520
ABSTRACT
Anthocyanin pigments in ten pigmented rice cultivars were isolated with cellulose thin-layer chromatography and preparative high performance liquid chromatography (HPLC), and further identified with conventional chromatographic techniques. Individual anthocyanins were then quantified by HPLC using a reversed ODS-5 column and detected at 280 nm. Ten rice varieties contained two major anthocyanins, cyanidin 3-glucoside and peonidin 3-glucoside. Total anthocyanin contents varied greatly in the range of 0-493 mg/100 g grain among varieties. Cyanidin 3-glucoside, an agent having important oxygen radical absorbing capacity (ORAC), was most abundant in Suwon #415 variety (470 mg/100 g grain), while Jawangdo (10 mg/100 g grain) and Ilpumbyeo (not detected) had the smallest amount of anthocyanin among the samples examined. As for the distribution ratio of individual anthocyanin, Suwon #415 was characterized by a relatively high percentage of cyanidin 3-glucoside (95.3%); whereas, Suwon #425 and Heugjinmi were characterized by a relatively larger amount of peonidin 3-glucoside.
Key words :anthocyanins, pigmented rice, black rice, cyanidin 3-glucoside, peonidin 3-glucoside, HPLC analysis