Antioxidant capacities of fucoxanthin-producing algae as influenced by their carotenoid and phenolic contents

Abstract

Natural antioxidants from sustainable sources are favoured to accommodate worldwide antioxidant demand. In addition to bioprospecting for natural and sustainable antioxidant sources, this study aimed to investigate the relationship between the bioactives (i.e. carotenoid and phenolic acids) and the antioxidant capacities in fucoxanthin-producing algae. Total carotenoid, phenolic acid, fucoxanthin contents and fatty acid profile of six species of algae (five microalgae and one macroalga) were quantified followed by bioactivity evaluation using four antioxidant assays. Chaetoceros calcitrans and Isochrysis galbana displayed the highest antioxidant activity, followed by Odontella sinensis and Skeletonema costatum which showed moderate bioactivities. Phaeodactylum tricornutum and Saccharina japonica exhibited the least antioxidant activities amongst the algae species examined. Pearson correlation and multiple linear regression showed that both carotenoids and phenolic acids were significantly correlated (p<0.05) with the antioxidant activities, indicating the influence of these bioactives on the algal antioxidant capacities.

Comparison of chemical profile and antioxidant properties of the brown algae

“…Foo et al . () reported that the ABTS of the microalgae Isochrysis galbana (21.55 mg TE g −1 alga) and Chaetoceros calcitrans (16.92 mg TE g −1 alga) was lower compared to the findings in our study.…”

“…In comparison with macroalgae, Foo et al . () showed that microalgae ( Chaetoceros calcitrans with 5.13 mg Fx g −1 alga) had higher fucoxanthin compared to macroalgae, and it could be up to 18.23 mg Fx g −1 alga in microalgae Isochrysis aff. galbana (Kim et al ., ).…”

“…Foo et al . () indicated the low antioxidant activity of the microalgae Chaetoceros calcitrans (1.65 mg TE g −1 alga) and Isochrysis galbana (1.96 mg TE g −1 alga). The FRAP values for the extracts of Kappaphycus alvarezzi and Padina antillarum were only 0.56 and 15.7 mg TE g −1 alga, respectively, as observed by Chew et al .…”

HPLC fucoxanthin profiles of a microalga, a macroalga and a pure fucoxanthin standard

“…Results were then expressed as milligram fucoxanthin per gram dry weight biomass (mg FX.g −1 .DW) as reported in Foo et al [1].…”

“…High performance liquid chromatography (HPLC) eluted fucoxanthin at the 7.008±0.024th min. This data article refers to the research article ‘‘Antioxidant capacities of fucoxanthin-producing algae as influenced by their carotenoid and phenolic contents’’ Foo et al [1]; where a more comprehensive data interpretation and analysis is explained.…”