Extraction and antioxidant activities of flavonoids, polyphenols, and polysaccharides from Hemerocallis fulva flowers

The flavonoids, polyphenols, and polysaccharides from 10 different varieties of Hemerocallis fulva flowers were extracted by ultrasonic-assisted extraction method, and the antioxidant activities of the extracts were evaluated. The results showed that the highest yield of polysaccharide, polyphenols and flavonoids in 10 Hemerocallis fulva flowers was 8.29%, 1.521%, and 1.743%, respectively. The results of antioxidant activities showed that the extracts of 10 species of Hemerocallis fulva flowers presented good scavenging rates for 1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) free radical and 2,2 '-diazo-di-3-ethylbenzothiazolin-6-sulfonic acid (ABTS) free radical. When the concentration of alcohol extract of ‘Muyangren’ variety was only 0.987 mg/mL, the scavenging rates of two kinds of free radicals were similar to V_C, reaching 92.38% and 99.79%, respectively. The results showed that the above 10 different varieties of Hemerocallis fulva were rich in flavonoids, polyphenols, and polysaccharides with good antioxidant activities, which could provide data support for the in-depth development of Hemerocallis fulva flowers.