The lactic acid bacteria are used in fermentation and the bio conservation of food, because it produces organic acids and other antibacterial substances as the bacteriocin to inhibit certain pathogenic stocks. In orde...The lactic acid bacteria are used in fermentation and the bio conservation of food, because it produces organic acids and other antibacterial substances as the bacteriocin to inhibit certain pathogenic stocks. In order to demonstrate the inhibitory effect of these bacteria, we studied the antagonistic capacity of the two leavens of yoghourt （Streptococcus thermophilus and Lactobacillus bulgaricus） and Bifidobacterium bifidum with respect to Helicobacterpylori by the method of diffusion by discs. Their interactions led to the emergence of large zones of inhibition. Bifidobacterium bifidum led the greatest halo with a diameter of 0.8 cm by contribution to Lactobacillus bulgaricus （0.5 cm） and Streptococcus thermophilus （0.3 cm）. The additional tests were required to know the exact nature of the inhibitors. The results showed that the antibacterial peptides （bacteriocins） have a narrow spectrum of activity against the species pathogen compared to that caused by acidity.展开更多
Cow＇s milk constitutes a significant food for babies when mother＇s milk is insufficient. The purpose of this work is to offer a fermented milk, potentially hypoallergenic, using selected Lactobaeillus acidophilus an...Cow＇s milk constitutes a significant food for babies when mother＇s milk is insufficient. The purpose of this work is to offer a fermented milk, potentially hypoallergenic, using selected Lactobaeillus acidophilus and Bifidobacteria sp. for their proteolytic activities. The fermentation is evaluated by the rate of lactic acid production and by the bacterial enumeration at 45 ℃. The rate of acidification obtained by mixed cultures （La ＋ B. longum, 63.8 ± 3.5 °D） and （La ＋ B. breve, 43.4 ± 1.67 °D） compared with the control （milk） （18.6 ± 1.31 °D）. The result of the best hydrolysis was obtained by （La＋ B. longum） （154.88 ± 30.33 ug/mg） which corresponded to a better release of the a-NH2 functions （103.32 ± 12.81 umoles/mg） compared with control （307.2 ± 11.54 ug/mg and 10.25 ± 0.44 umoles/mg ）. The best synergy was obtained by （La ＋ B. bifidum） （13 × 10^6 cfu/mL and 60 × 10^6 cfu/mL） and reached 95 × 10^10 cfu/mL and 119 × 10^10 cfu/mg at the end. The electrophoresis of fermented milk revealed the presence of soluble proteins （a-Lactalbumin and β-Lactoglobulin）. The Enzyme Linked Immtmo Sorbent Assay showed the results of residual antigenic activities of β-Lg （1.4 ± 0.23 ug/mg）, a-La （0.012 ± 0.004 ug/mg） and bovin serum albumin （0.014 ± 0.005 ug/mg）by the associations （La ＋ B. longum）, （La ＋ B. bifidum） and （La ＋ B. bifidum） compared with the control （14.43 ± 5.91 ug/mg, 0.183 ± 0.062 gg/mg, 0.05 ± 0.008 ug/mg） respectively. Lactic fermentation reduced to a significant antigenic reactivity of principal whey milk proteins.展开更多
Salmonella enterica serovar typhimurium is the first cause identified of food poisoning in humans; new data indicate that the resistant strains of Salmonella sp. can be inhibited by a bacterial population present in f...Salmonella enterica serovar typhimurium is the first cause identified of food poisoning in humans; new data indicate that the resistant strains of Salmonella sp. can be inhibited by a bacterial population present in foods have been called probiotics. Our study was conducted on Swiss albino mice in order to know the effect of probiotics or biotherapeutic agents, and suggest the different therapeutic possibilities of intestinal complications related to the presence of Salmonella enterica serovar typhimurium; Reference strains, Lactobacillus delbrueckii subsp, bulgaricus, Lactobacillus acidophilus and Lactobacillus paracasei in combination with Bifidobacterium sp. were tested for their health benefits. The number of Salmonella enterica serovar typhimurium decreases in intestine, in the stomach and in the liver for group 2, 3 in case of preventive treatment and group 4, 5 in case of a therapeutic treatment due to the use of a cuRure of probiotics, in comparison with group 1 where we recorded a high number. The bio-therapeutic treatment was finally confirmed by macroscopic and microscopic observations of different target organs before and after treatment for the experiment period.展开更多
文摘The lactic acid bacteria are used in fermentation and the bio conservation of food, because it produces organic acids and other antibacterial substances as the bacteriocin to inhibit certain pathogenic stocks. In order to demonstrate the inhibitory effect of these bacteria, we studied the antagonistic capacity of the two leavens of yoghourt （Streptococcus thermophilus and Lactobacillus bulgaricus） and Bifidobacterium bifidum with respect to Helicobacterpylori by the method of diffusion by discs. Their interactions led to the emergence of large zones of inhibition. Bifidobacterium bifidum led the greatest halo with a diameter of 0.8 cm by contribution to Lactobacillus bulgaricus （0.5 cm） and Streptococcus thermophilus （0.3 cm）. The additional tests were required to know the exact nature of the inhibitors. The results showed that the antibacterial peptides （bacteriocins） have a narrow spectrum of activity against the species pathogen compared to that caused by acidity.
文摘Cow＇s milk constitutes a significant food for babies when mother＇s milk is insufficient. The purpose of this work is to offer a fermented milk, potentially hypoallergenic, using selected Lactobaeillus acidophilus and Bifidobacteria sp. for their proteolytic activities. The fermentation is evaluated by the rate of lactic acid production and by the bacterial enumeration at 45 ℃. The rate of acidification obtained by mixed cultures （La ＋ B. longum, 63.8 ± 3.5 °D） and （La ＋ B. breve, 43.4 ± 1.67 °D） compared with the control （milk） （18.6 ± 1.31 °D）. The result of the best hydrolysis was obtained by （La＋ B. longum） （154.88 ± 30.33 ug/mg） which corresponded to a better release of the a-NH2 functions （103.32 ± 12.81 umoles/mg） compared with control （307.2 ± 11.54 ug/mg and 10.25 ± 0.44 umoles/mg ）. The best synergy was obtained by （La ＋ B. bifidum） （13 × 10^6 cfu/mL and 60 × 10^6 cfu/mL） and reached 95 × 10^10 cfu/mL and 119 × 10^10 cfu/mg at the end. The electrophoresis of fermented milk revealed the presence of soluble proteins （a-Lactalbumin and β-Lactoglobulin）. The Enzyme Linked Immtmo Sorbent Assay showed the results of residual antigenic activities of β-Lg （1.4 ± 0.23 ug/mg）, a-La （0.012 ± 0.004 ug/mg） and bovin serum albumin （0.014 ± 0.005 ug/mg）by the associations （La ＋ B. longum）, （La ＋ B. bifidum） and （La ＋ B. bifidum） compared with the control （14.43 ± 5.91 ug/mg, 0.183 ± 0.062 gg/mg, 0.05 ± 0.008 ug/mg） respectively. Lactic fermentation reduced to a significant antigenic reactivity of principal whey milk proteins.
文摘Salmonella enterica serovar typhimurium is the first cause identified of food poisoning in humans; new data indicate that the resistant strains of Salmonella sp. can be inhibited by a bacterial population present in foods have been called probiotics. Our study was conducted on Swiss albino mice in order to know the effect of probiotics or biotherapeutic agents, and suggest the different therapeutic possibilities of intestinal complications related to the presence of Salmonella enterica serovar typhimurium; Reference strains, Lactobacillus delbrueckii subsp, bulgaricus, Lactobacillus acidophilus and Lactobacillus paracasei in combination with Bifidobacterium sp. were tested for their health benefits. The number of Salmonella enterica serovar typhimurium decreases in intestine, in the stomach and in the liver for group 2, 3 in case of preventive treatment and group 4, 5 in case of a therapeutic treatment due to the use of a cuRure of probiotics, in comparison with group 1 where we recorded a high number. The bio-therapeutic treatment was finally confirmed by macroscopic and microscopic observations of different target organs before and after treatment for the experiment period.
