Comparison of ecklonia cava, ecklonia stolonifera and eisenia bicyclis for phlorotannin extraction

Phlorotannins are polyphenols of marine algae, particularly brown seaweed, having multiple biological activities. A reverse phase-high performance liquid chromatography method was developed for rapid and routine quantification of two major phlorotannins, dieckol and phlorofucofuroeckol- A(PFE- A), from boiling water- And organic solvent-extracts of brown seaweeds Ecklonia cava, E. stolonifera and Eisenia bicyclis. The regression equations for dieckol and PFE- A were as follows: The concentration (mg ml-1) = 16.56 × peak height (cm) + 0.44, and the concentration = 20.60 × peak height (cm) + 0.11, with correlation coefficients of 0.996 and 0.999, respectively. Compared to organic solvent extraction, the recovery yield of dieckol from boiling water extracts of E. cava, E. stolonifera and E bicyclis was 86%, 93%, and 98%, respectively. The recovery yield of PFE- A was 74%, 86% and 62%, respectively. Antioxidant activity was detected in each E. bicyclis water extract (91%), followed by E stolonifera (90%) and E cava (74%). Dieckol and PFE- A showed almost 9- And 7-fold stronger antioxidant activity than the standard butylhydroxytoluene, and 6- And 4-fold greater than L- Ascorbicacid in molar concentration, respectively.