Effect of ultrasounds and ball milling on the bioaccessibility of carotenoids from the microalga Dunaliella bardawil

Abstract

This study evaluated the bioaccessibility of carotenoids from wild-type and phytoene-enriched Dunaliella bardawil biomass treated by ultrasounds and ball-milling. Fresh, freeze-dried, and alginate-encapsulated matrices were studied. The impact of yogurt addition was also evaluated on freeze-dried samples. Carotenoid bioaccessibility varied significantly depending on the matrix, treatment, and carotenoid isomer. As an example, ballmilling at 30 Hz was the treatment leading to the highest bioaccessibility in fresh samples (p < 0.05), whereas this treatment at 5 Hz was optimal for freeze-dried matrices, with no significant differences with the control in the wild-type matrix. The addition of yogurt enhanced carotenoid bioaccessibility (p < 0.05) in both freeze-dried matrices. Xanthophylls showed slightly higher bioaccessibility than carotenes, and cis-isomers outperformed their all-trans counterparts. (15Z)-Phytoene and (all-E)-lutein showed the greatest bioaccessibility in most treatments. These results can help improve the bioavailability of carotenoids from D. bardawil through optimized pretreatment strategies.