Antioxidative activities of cells and different cellular fractions of lactic acid bacteria

• Main Authors: Wei-Li Lin, 林微利
• Other Authors: 林美吟
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/35897870050450520892

碩士 === 國立中興大學 === 食品暨應用生物科技學系 === 94 === Antioxidative ability of lactic acid bacteria including Bifidobacterium longum B6, B. longum 15708, Lactobacillus bulgaricus 1006 and Streptococcus thermophilus 3641 were examined in vitro. The fractions of lactic acid bacteria including intact cells, heat-killed cells, intracellular fractions, heat-treated intracellular fractions and cell wall were used for our study. The different bacterial concentration including 1010, 109, 108 CFU/mL were used. The best antioxidative ability of the fractions of lactic acid bacteria was further used for study on interleukin-8 (IL-8) secretion in H2O2-treated Caco-2 cells. The cell model can evaluate the protective effects of the fractions of lactic acid bacteria against H2O2-induced oxidative stress. Antioxidative abilities including TEAC, scavenging ability of DPPH, scavenging ability of H2O2, scavenging ability of OH• and chelating ability on ferrous ions were determined. The antioxidative ability of lactic acid bacteria depended on difference of strains and number of bacterium and expressed strain-dependent manners. Heat-treated intracellular fractions of B. longum B6 were highest TEAC (291.3μM). Scavenging ability of DPPH was more than 80% by all of these four lactic acid bacteria. Scavenging ability of H2O2 was higher than other fractions by heat-treated intracellular fractions of B. longum B6, B. longum 15708 and S. thermophilus 3641 (81.8, 67.7 and 55.1%), and heat-killed cells of L. bulgaricus 1006 (88.9%). Scavenging ability of OH• was different with difference of strains and fractions. Heat-killed cells of B. longum B6 and L. bulgaricus 1006 (88.1 and 92.5%), and heat-treated intracellular fractions of B. longum 15708 and S. thermophilus 3641 (72.3 and 93.5%) exhibited higher chelating ability on ferrous ions. Heat-killed cells, intracellular fractions and heat-treated intracellular fractions of B. longum B6, B. longum 15708, L. bulgaricus 1006 and S. thermophilus 3641 significantly decreased IL-8 secretion of Caco-2 cell.