Encapsulation of carotenoids extracted from halophilic Archaea in oil-in-water (O/W) micro- and nano-emulsions

Marwa Chaari, Ioanna Theochari, Vassiliki Papadimitriou, Aristotelis Xenakis, Emna Ammar

National Engineering School in Sfax, University of Sfax, UR: Costal and Urban Environments, B.P. 1173, 3038 Sfax, Tunisia.

Abstract

Carotenoids extracted from halophilc Archaea have potential health benefits. Their poor water-solubility and low bioavailability is a challenge to their incorporation into foods. The aim of this work was the carotenoids encapsulation into two oil-in-water (O/W) dispersions, to increase their use as functional food applications. A nanoemulsion produced by high pressure homogenization and a spontaneously formed microemulsion were conceived. The limonene was the dispersed oil phase, and mixtures of Triton X-100/Tween-80 (3:1) as emulsifiers and of water/glycerol (2:1) as the continuous aqueous phase. The microemulsion monophasic area was determined through the pseudo-ternary phase diagram. Dynamic Light Scattering was used for the structural characterization of the nano- and micro-emulsions in the presence of the carotenoids. Moreover, the radical scavenging activity of the encapsulated carotenoids was examined by Electron Paramagnetic Resonance spectroscopy. The results confirmed the delivery systems design effectiveness to encapsulate and stabilize the carotenoids for food applications.

Graphical abstract

Keywords: Nanoemulsion, Microemulsion, Dynamic Light Scattering, Electron Paramagnetic Resonance, Antioxidant activity.