Pulsed electric field and pH assisted selective extraction of intracellular components from microalgae Nannochloropsis

The study was aimed at investigation of the potential of pulsed electric field (PEF) pre-treatment as a preliminary step of pH-assisted aqueous extraction of algae components from microalgae Nannochloropsis suspensions. The PEF and sonication (S) were compared as pretreatment methods. They were applied at normal (pH = 8.5) and basic (pH = 11) conditions, and supplementary basic extraction (at pH = 11) was done. The extracts were analyzed for content of pigments, proteins, carbohydrates, total phenolic compounds and antioxidant capacity. The colloidal stability of PEF- and S-pretreated suspensions was also evaluated. The data evidence that PEF technique allows selective extraction of a portion of pure proteins that are different from proteins extracted from S-pretreated suspensions. The discovered effects have shown the advantages of PEF-pretreatment at normal conditions (pH = 8.5) and supplementary extraction at basic conditions (pH = 11) for selective extraction of different intracellular components. (C) 2015 Elsevier B.V. All rights reserved.