The antioxidative properties of phlorotannins isolated from the brown alga Eisenia bicyclis were measured using the H-ORAC (Hydrophilic Oxygen Radical Absorbance Capacity) method. The ORAC values of phloroglucinol and...The antioxidative properties of phlorotannins isolated from the brown alga Eisenia bicyclis were measured using the H-ORAC (Hydrophilic Oxygen Radical Absorbance Capacity) method. The ORAC values of phloroglucinol and it’s oligomers: eckol, fucofuroeckol A, phlorofucofuroeckol A, dieckol, 8,8’-bieckol, were 2.57 ± 0.14, 4.97 ± 0.36, 9.82 ± 0.70, 8.97 ± 0.89, 10.22 ± 0.85, 8.62 ± 0.92 μmol Trolox equivalent/μmol, respectively. With the exception of eckol, the ORAC values of tested phlorotannins were higher than those of the well-known antioxidants (epigallocatechin gallate, resveratrol and L-ascorbic acid) used as positive controls. As a result of comparing with known ORAC values, it was found that the dieckol and fucofuroeckol A had stronger antioxidant activity than representative polyphenols (e.g., kaempferol, quercetin, myricetin and chlorogenic acid) derived from terrestrial plants.展开更多
文摘The antioxidative properties of phlorotannins isolated from the brown alga Eisenia bicyclis were measured using the H-ORAC (Hydrophilic Oxygen Radical Absorbance Capacity) method. The ORAC values of phloroglucinol and it’s oligomers: eckol, fucofuroeckol A, phlorofucofuroeckol A, dieckol, 8,8’-bieckol, were 2.57 ± 0.14, 4.97 ± 0.36, 9.82 ± 0.70, 8.97 ± 0.89, 10.22 ± 0.85, 8.62 ± 0.92 μmol Trolox equivalent/μmol, respectively. With the exception of eckol, the ORAC values of tested phlorotannins were higher than those of the well-known antioxidants (epigallocatechin gallate, resveratrol and L-ascorbic acid) used as positive controls. As a result of comparing with known ORAC values, it was found that the dieckol and fucofuroeckol A had stronger antioxidant activity than representative polyphenols (e.g., kaempferol, quercetin, myricetin and chlorogenic acid) derived from terrestrial plants.
