标题:Effect of solvents and extraction methods on total anthocyanins, phenolic compounds and antioxidant capacity of Renealmia alpinia (Rottb.) Maas peel
摘要:The effect of different solvents and extraction methods on total anthoc yanins, phenolic compounds, and antioxidant capacity from x´kijit ( renealmia alpinia Rottb. Maas) peels was evaluated. In order to evaluate the effect of solvents on the bioactive compounds extraction efficienc y and antioxidant capacity, a special cubic mixture design model was implemented with ethanol, methanol, and acetone as solvents and conventional (agitation – 1 and 6 h; Soxhlet – 2 and 4 h), novel (power ultrasound – 2.5 and 5 min) methods, and combination of extraction methods. Acceptable correla - tions between predicted and experimental data were obtained for total anthoc yanins ( r 2 = 0.95), phenolic compounds ( r 2 = 0.78), and antioxidant capacity ( r 2 = 0.97), with methanol exhibiting the highest extraction yield of bioactive compounds and resultant antioxidant capacity. Although the extraction of total anthocyanins (82.2–85.8 mg cyanidine/ kg) and phenolic compounds (183.6–207.0 mg GAE/kg) was best carried out through Soxhlet, the ultrasonic treat- ment showed similar antioxidant capacity values (27.4–34.3 mg Trolox/kg) to those of 2-h Soxhlet. Moreover, a 5-min ultrasound pretreatment significantly increased ( p < 0.05) phenolic compounds by 11, 21 and 12% when combined with agitation 1, 6, and 2-h Soxhlet treatments, respectively ; while the antioxidant capacity increased by 26, 48, and 22% for the same treatments. Ultrasound might be used as a valuable, green alternative procedure for improving the solvent extraction of bioactive compounds.