Chia seed mucilage (CM), flaxseed mucilage (FM), and inulin (INL) were used as encapsulating agents to evaluate the possibility of increasing the survival of Lactobacillus casei var. rhamnosus, renamed recently to Lacticaseibacillus rhamnosus, after spray drying. Moreover, the viability of encapsulated L. rhamnosus was determined during the 250 day storage period at 4 °C. In a second stage, the conditions that maximized the survival of L. rhamnosus were evaluated on other probiotic bacteria (Lactiplantibacillus plantarum, Bifidobacterium infantis, and Bifidobacterium longum). Additionally, the viability of encapsulated probiotics during the 60 day storage period at 4 and 25 °C was evaluated. The conditions that maximize the survival of L. rhamnosus (90%) predicted by a face-centered central composite design were 14.4% w/v of maltodextrin, 0.6% w/v of CM, and 90 °C of inlet air temperature. Additionally, under these encapsulating conditions, the survival of L. plantarum, B. infantis, and B. longum was 95%, 97%, and 96%, respectively. The probiotic viability improved during storage at 4 °C but decreased at 25 °C. The highest viability values obtained for probiotics during spray drying and during storage suggest a thermoprotector effect of CM, which would ensure an optimal probiotic efficacy in the product, thus promoting its utilization in the food industry.

Eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and carotenoids are needed as human dietary supplements and are essential components in commercial feeds for the production of aquacultured seafood. Microorganisms such as thraustochytrids are potential natural sources of these compounds. This research reports on the lipid and carotenoid production capacity of thraustochytrids that were isolated from coastal waters of Antarctica. Of the 22 isolates, 21 produced lipids containing EPA+DHA, and the amount of these fatty acids exceeded 20% of the total fatty acids in 12 isolates. Ten isolates were shown to produce carotenoids (27.4–63.9 μg/g dry biomass). The isolate RT2316-16, identified as Thraustochytrium sp., was the best producer of biomass (7.2 g/L in five days) rich in carotenoids (63.9 μg/g) and, therefore, became the focus of this investigation. The main carotenoids in RT2316-16 were β-carotene and canthaxanthin. The content of EPA+DHA in the total lipids (34 ± 3% w/w in dry biomass) depended on the stage of growth of RT2316-16. Lipid and carotenoid content of the biomass and its concentration could be enhanced by modifying the composition of the culture medium. The estimated genome size of RT2316-16 was 44 Mb. Of the 5656 genes predicted from the genome, 4559 were annotated. These included genes of most of the enzymes in the elongation and desaturation pathway of synthesis of ω-3 polyunsaturated fatty acids. Carotenoid precursors in RT2316-16 were synthesized through the mevalonate pathway. A β-carotene synthase gene, with a different domain organization compared to the gene in other thraustochytrids, explained the carotenoid profile of RT2316-16.