Bioactive phenols in algae: The application of pressurized-liquid and solid-phase extraction techniques

Abstract

Nová extrakční metoda založená na kombinaci extrakce kapalina-tuhá fáze (PLE-SPE) byla použita pro extrakci bioaktivních fenolických látek z in vitro kultur dvou sladkovodních řas (Anabaena doliolum and Spongiochloris spongiosa) a z potravních produktů z mořských řas Porphyra tenera (nori) a Undaria pinnatifida (wakame). Analýzy prokázaly, že ve sladkovodních řasách a produktech z mořských řas byly fenolické látky obsaženy v hodnotách mikrogramů na gram lyofylizovaného vzorku. Dále byl stanoven celkový obsah fenolických látek (Folin?Ciocalteu metoda) a antioxidační aktivita (TEAC metoda) PLE-SPE extraktů.

A new extraction technique based on the off-line combination of pressurized-liquid with solid-phase extraction (PLE?SPE) is described. Themethodwas used for the extraction of bioactive phenolic acids (protocatechuic, p-hydroxybenzoic, 2,3-dihydroxybenzoic, chlorogenic, vanillic, caffeic, p-coumaric, salicylic acid), cinnamic acid and hydroxybenzaldehydes (p-hydroxybenzaldehyde, 3,4-dihydroxybenzaldehyde, vanillin) from in vitro culture of two freshwater algae (Anabaena doliolum and Spongiochloris spongiosa) and fromfood products of marine macroalgae Porphyra tenera (nori) andUndaria pinnatifida(wakame). For the identification and quantification of the compounds the molecular ions [M?H]? and specific fragments were analyzed by quadrupole mass spectrometry analyzer connected on-line with a reversed-phase HPLC system. Our analysis showed that the freshwater algae and marine algal products contained submicrogram or microgram level of above-mentioned phenols per gram of lyophilized sample. In addition, the total phenol content (Folin?Ciocalteu assay) and antioxidant activity (TEAC assay, Trolox equivalent antioxidant capacity assay) of the PLE?SPE extracts were determined and discussed.