The Effects Of Pre-Encapsulation Technology On Saccharomyces Boulardii

The technology of preparation of calcium alginate microcapsule by emulsification/internal gelations is not enough perfect and needs further optimization.Liquid paraffin is often used as oil phase of preparation of calcium alginate microcapsule in this technology.Considering that cooking oil is safer than liquid paraffin in the food,health care,medical and feed industry,using soybean oil instead of liquid paraffin to prepare probiotics microcapsules have higher research value.On the other hand,pre-encapsulated probiotics are grown in microcapsules that have complex micro-environments and present clusters of high-density growth which can lead to the physiological and biochemical changes of probiotics coated by the calcium alginate microcapsules.With saccharomyces boulardii as the study subject,the effects of pre-encapsulation technology on saccharomyces boulardii were studied preliminarily in this paper.On the one hand,with soybean oil as oil phase to prepare microcapsules of saccharomyces boulardii microcapsules,the quality of the microcapsules was evaluated preliminarily and the technology of preparing microcapsules of saccharomyces boulardii by soybean oil was optimized according to the quality difference with liquid paraffin.Then the microencapsulated saccharomyces boulardii prepared by soybean oil were cultured to evaluate the growth of saccharomyces boulardii in the microcapsules.On the other hand,the living bacteria count,the content of glucose and ethanol of microencapsulated saccharomyces boulardii and the substances of stress resistance,such as intracellular glycerol and intracellular trehalose,were detected to explore that the pre-encapsulated technology has an effect on saccharomyces boulardii.In addition,the effect of the pre-encapsulated technology on saccharomyces boulardii was studied at the molecular level by RNA-sequence.The results show that:(1)Compared with the liquid paraffin group,the quality of microcapsules produced by soybean oil as oil phase is different;The optimized conditions for preparing microcapsules by soybean oil is that the optimum concentration of sodium alginate was 20 g/L;Compared with the liquid paraffin group,the growth and metabolism of the microencapsulated saccharomyces boulardii were not significantly different in process of proliferation and growth.(2)Saccharomyces boulardii can grow well in calcium alginate microcapsules,and glucose and ethanol are well metabolized.Furthermore,for microencapsulated saccharomyces boulardii,the contents of intracellular glycerol and trehalose which are substances of stress resistance were significantly higher at 18 h and 24 h,which indicate that the pre-encapsulation technology make the content of intracellular glycerol and intracellular trehalose of saccharomyces boulardii increased and the pre-encapsulated saccharomyces boulardii is more resistant to stress.(3)Compared to free cells,there are 1439 differentially expressed genes in the pre-encapsulated saccharomyces boulardii,including 286 up-regulated genes and 1153 down-regulated genes;Through Gene Ontology(GO)analysis,the saccharomyces boulardii 's GO items affected by the pre-encapsulated technology were structural molecule activity,ribonucleoprotein complex,gene expression,organic acid metabolic process,small molecule metabolic process,carboxylic acid metabolic process,oxoacid metabolic process,organonitrogen compound metabolic process and amino acid metabolic process;Through Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis,the pre-encapsulated technology has an impact on metabolic pathways of saccaromyces boulardii,including ribosome,biosynthesis of amino acids,biosynthesis of antibiotics,biosynthesis of secondary metabolites,metabolic pathways and ribosome biogenesis in eukaryotes;Through screening analysis of differentially expressed genes,the expression of genes associated with glycerine and trehalose were significantly increased,in addition,the expression of genes associated with high temperature resistance and anti-oxygen stress was significantly increased.