OPTIMIZATION OF ANTHOCYANIN EXTRACTION FROM BLACK GLUTINOUS RICE (Oryza rufipogon)

Abstract

This study aimed to evaluate the effects of different extraction techniques, including microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and enzyme-assisted extraction (EAE), on the recovery and optimization of anthocyanins from black glutinous rice (Oryza rufipogon). The results indicated that UAE achieved the highest efficiency and was therefore selected for further optimization using a Box-Behnken design combined with response surface methodology. The optimal conditions were determined as ultrasound amplitude of 31.73%, extraction time of 6.97 min, and solid-to-solvent ratio of 1/21.62 (w/v), under which the anthocyanin content reached 0.964 mg/g dry weight. Experimental validation yielded 0.945 ± 0.028 mg/g dry weight, with a deviation of less than 5% from the predicted value. These findings confirm the potential of UAE combined with statistical optimization in enhancing anthocyanin recovery from black glutinous rice, contributing to the development of high-value food and pharmaceutical products.