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This study was designed to explore the production of bacteriocin Pediococcus optimal conditions, bacteriocin antibacterial spectrum and dairy corrosion, so as to further improve the basic research the lactic acid Pediocin the, its the enlargement industrial production and in food preservation to provide a theoretical basis and applied research in corrosion. A Pediococcus isolated from kimchi-based study of fermentation conditions by orthogonal test results found the lactic acid Pediocin the production related to the nature of the strain, the production of other fermentation conditions Pediocin also has a great influence and activity, such as culture medium composition, medium pH, culture temperature and culture time, the test to determine the strain produced pediocin optimal medium composition [g / L]: peptone, beef extract, culture pH was 6.0, yeast powder, glucose 15, Tween 80, dipotassium hydrogen phosphate, sodium acetate, sodium 5 citrate, ammonium sulfate, magnesium sulfate 0.8, manganese sulfate 0.2 optimization, the optimization of culture temperature and culture time were 37 ° C and 16h. Optimized medium based on several common potency determination methods such as double dilution method, Oxford Cup and a single colony plate method, and ultimately determine the combined dilution method with Oxford Cup wears for the determination of Pediococcus the agglutinin titer method is more accurate; choose foods common corruption and pathogenic micro-organisms as indicator bacteria, the use of the Oxford Cup, Determination of Pediocin the inhibitory spectrum, the results show that, Pediocin Lactobacillus plantarum and monocytes histiocytosis listeria significantly inhibited, no significant inhibitory effect against Staphylococcus aureus, Escherichia coli O157, Pseudomonas aeruginosa, Salmonella. In order to enhance the antibacterial activity of bacteriocins to improve the inhibitory effect, the paper attempts to pediocin and nisin composite act on the indicator bacteria. The results showed that the antibacterial activity of Lactobacillus plantarum indicator bacteria, composite bacteriocin 1.7-fold increase than a single bacterial factors, preliminary exploration on this basis, the optimum ratio of the two bacteriocins, its synergy The mechanism for the further study of bacteriocin inhibitory mechanism provides a theoretical support. The experiment also discussed Pediocin yogurt corrosion and preservation, and found that after 30 days to add the pediocin the samples listeria number was reduced by 2.90 log CFU / mL and 2.56 log CFU / mL, but did not add the pediocin the yogurt listeria the only reduces the number of 1.32 log CFU / mL. This result suggests that Pediocin able to control the growth of Listeria in dairy thereby enhancing food security.
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