Ca-Alginate-Carob Galactomannans Beads to Preserve Viability During Digestive Hostility Transit and Cholesterol Uptake Ability of Probiotic Bacteria

International audienceThe assurance of the bacteria survival is the key of the protective technique aiming to alleviate the bacteria resistance under digestive hostilities. Among the methods of protection, microencapsulation of cells in various biomaterials has given convincing results. We tried to exploit for the first time the emulsifying properties of carob galactomannans reinforced herein by the sodium alginate gel in the microencapsulation of beneficial bacteria. On the other hand, we explored the benefits of this protective technique upon the expression of the bacterial ability to uptake cholesterol, in complement to our previously published results. The present study aimed to develop a new mixed gel containing calcium alginate and galactomannans extracted from the Algerian carob seeds endospermes, for the microencapsulation of the human strain of Lactobacillus rhamnosus LbRE-LSAS; compared with the probiotic strain of Bifidobacterium animalis subsp. lactis Bb12. Influence of microencapsulation was tested under simulated digestive environment to verify if both bacteria preserve their viability and their cholesterol assimilation ability. High viable loads of encapsulated LbRE-LSAS and Bb12 were registered (6.97 and 8.66 of 10 Log CFU g −1 , respectively). Conversely, the free cell levels strongly (P < 0.05) decreased during exposure to the digestive simulated conditions. According to our results, the new formed gel permits to improve 1.8-fold on average the cholesterol assimilation ability of probiotic bacteria. We underlined the possible use of carob galactomannans-Ca-alginate beads as alternative healthy solution in protecting beneficial bacteria under gastro-intestinal conditions, and by the way, lowering the serum cholesterol level in the host

Anaerobic probiotics: the key microbes for human health

Human gastrointestinal microbiota (HGIM) incorporate a large number of microbes from different species. Anaerobic bacteria are the dominant organisms in this microbial consortium and play a crucial role in human health. In addition to their functional role as the main source of many essential metabolites for human health, they are considered as biotherapeutic agents in the regulation of different human metabolites. They are also important in the prevention and in the treatment of different physical and mental diseases. Bifidobacteria are the dominant anaerobic bacteria in HGIM and are widely used in the development of probiotic products for infants, children and adults. To develop bifidobacteria-based bioproducts, therefore, it is necessary to develop a large-scale biomass production platform based on a good understanding of the ideal medium and bioprocessing parameters for their growth and viability. In addition, high cell viability should be maintained during downstream processing and storage of probiotic cell powder or the final formulated product. In this work we review the latest information about the biology, therapeutic activities, cultivation and industrial production of bifidobacteria