Studies on the antioxidant components and activities of the methanol extracts of commercially grown Hemerocallis fulva L (daylily) in Taiwan

We explored the antioxidant components and activities of daylily Hemerocallis fulva L. flowers among two growth areas, three flower ages and two processing methods. The results showed that the growth area, flower age and processing method all significantly influenced the functional components and antioxidant activities grown in mountainous areas of Taiwan. The total phenols, flavonoids and total chlorophylls of the methanol extracts of D3DF were 59.51, 70.76 and 5.67% of the respective values of F3DF. The total phenols and anthocyanins of the methanol extracts of F1DF were 2.64 mg GAE/100 g·dried basis (db) and 0.102 µmole/100 g·db, which were significantly higher than the others. The total flavonoid contents of F1DF, F2DF, F3DF and D3DF were 20.83, 29.67, 31.65 and 22.30 mg QE/100 g·db, respectively, with the F1DF level as the lowest. The reducing power showed that both the fresh and dried flowers were very weak. The amounts of most flavonoids in the flowers from Hualien were greater than those from Taidong.