The immunomodulation activity and probiotic application for the multispecises combination of lactic acid bacteria

• Main Author: 梁馨文
• Other Authors: 蔡政志
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/26310126770478738367

碩士 === 弘光科技大學 === 生物產業研究所 === 96 === The animal farming industry usually supplemented the antibiotics or drugs in feed to prevent the pathogens infection for animals. Recently, the multi-drug resistance problem seriously affect the animal therapy. Probiotics such as Lactobacillus spp., Bifidobacteria spp., Enterococcus spp., Lactococcus spp. and Streptococcus spp. etc. can enhance the immune system or produce the bacteriocin to reduce the infection by pathogens. The mechanisms of probiotics against gastrointestinal pathogens infection addressed in diverse patent applications include: (i) modification of the environmental conditions, (ii) competition with pathogens for nutrients and adhesion sites, (iii) production of antimicrobial metabolites and (iv) modulation of the immune and non-immune defense mechanisms of the host. The aim of this study was to evaluate the effective lactic acid bacteria strains and used these strains for multispecis or multigenera probiotics preparation. The immune effect of these strains will be evaluated in vitro using macrophage (RAW 264.7) cell line. Antimicrobial activity for lactic acid bacteria strains against the growth of pathogenic bacteria including Enterotoxigenic Staphylococcus aurcus spp., Salmonella spp., ETEC and EHEC etc cetera, and the adhesionof these LAB cells to Caco-2 cell line will be evaluated. Concentration effect study for lactic acid bacteria to stimulate macrophage (RAW 264.7) and induce TNF-α production showed that 107~108 CFU/ml were the optimal concentration. Criteria for section of strains of LBR01, Bi5, LPL05, LF01, LRE01, LJ01 and BV8 was based on the data of TNF-α and NO production. For ECA01 and BCRC 14608 strains, the critiae was based on the high quantity of IFN-γ and NO production. The adhesion study using cultured human intestinal Caco-2 cell line showed that LAB strains BV8、LA5、LF33、TM39 and LPL05 were candidate strains. On the other hand, antimicrobial activity for the spent culture supernatants (SCS) of the LAB strains against pathogenic strains indicated that strains LC01 and LPR01 were with higher antagonistic activity. Different probiotic strains with superior function were screened and then combined. The multispecies combination and their immune effect were than in vitro evaluated by stimulation of the macrophage (RAW 264.7) and induction of the TNF-α production. Based on the results, BALB/c mice were orally administered with different multispecies probiotics for sixty-three consecutive days followed by challenging these mice by oral administration of Salmonella typhimurium on the 64th day. Results showed that, for mice with multispecies probiotics treatment, Lactobacillus counts in their feces microflora increased. For these mice the phagocytic activity in peritoneal macrophages increased too. At day 8 after the challenge, the mice which had received multispecies probiotics exhibited significantly reduction of Salmonella invasion into their liver and spleen as compared to the control without probiotic administration. Our findings suggested that multispecies probiotics may be more efficient than monostrain probiotics due to the enhanced effect on intestinal adhesion, competition for nutrients, and the production of a greater range of antimicrobial compounds no compared with the results from monostrainsingle strain probiotics. In the future, attempt to combine these probiotic strains and use of them for the therapy of children and animal disease will be performed.