Naslov
Comparison of two Dictyota species (Brown seaweeds) based on their antioxidant activity

Autori
Čož-Rakovac Rozelindra, Čižmek Lara, Martić Ana, Babić Sanja, Trebše Polonca

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
World Aquaculture 2021 : Abstracts / - , 2022, 45-45

Skup
World Aquaculture 2021

Mjesto i datum
Mérida, Meksiko, 24.05.2022. - 27.05.2022

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Dictyota species ; antioxidant activity ; square-wave voltammetry

Sažetak
Marine macroalgae or seaweeds are in a continuous focus of the scientific community, but even in the focus of a wider public as they are acknowledged as a valuable source of different bioactive compounds such as polyphenols, peptides, pigments, and polysaccharides that are associated with several health benefits and biological activities. Brown algae are known for their accumulation of specific metabolites with great antioxidant potential. In this study, we evaluated the antioxidant activity of different fractions from two brown macroalgae, Dichtyota dichotoma, and Dichtyota fasciola. The primarily used method was square-wave voltammetry (SWV), followed by the reduction of the radical cation (ABTS), the 2, 2-diphenyl-1-picryl-hydrazyl (DPPH) assay, the Folin–Ciocalteu, and the oxygen radical absorbance capacity (ORAC) assays. To correlate obtained results for antioxidant activity, Pearson’s correlation coefficient was used. Toxicity evaluation of obtained fractions revealed the safety of their usage and further implementation. In this research, the dry residues of extracts from brown macroalgae samples were immobilized on the surface of GCE and immersed into a 0.1 mol/L phosphate buffer solution. To evaluate their activity and optimal electrochemical response, a change in the pH values, ranging from 3 to 11, for all obtained extracts was tested. To assess antioxidant activity using voltammetric analysis, the area under the curve (AUC) was integrated, the value of which represents an estimate of the total antioxidant activity of the extracts. The highest antioxidant activity based on the AUC value was obtained for D. fasciola F2 (0.099±0.001 mg/g GAE) followed by D. fasciola F3 (0.068±0.006 mg/g GAE) > D. dichotoma F3 (0.050±0.002 mg/g GAE) > D. dichotoma F2 (0.028±0.002mg/g GAE). No significant difference in antioxidant activity was observed between fractions of two Dictyota species. Other employed spectrophotometric methods also revealed similar behavior of two Dictyota species, however, somewhat higher activity was observed for both D. dichotoma fractions. The Pearson’s correlation coefficient for SWV versus Folin-Ciocalteu method was a negative value of -0.99 (p<0.05). For other spectrophotometric methods, there was no statistically significant correlation obtained with SWV. Also, a high negative correlation between DPPH and Folin-Ciocalteu assay was observed with Pearson’s correlation coefficient of -0.81. Correlations indicate that the synergistic effect of different compounds extracted from the samples impacted their antioxidant response. All three researched brown macroalgae have shown to be a potent source of natural antioxidants that could further be used in the research of oxidative stress-related diseases.

Izvorni jezik
Engleski

Znanstvena područja
Kemija, Nutricionizam

POVEZANOST RADA