The invention discloses a composite
enrichment culture medium capable of simultaneously enriching three food-borne
pathogenic bacteria, namely
Listeria monocytogenes,
Escherichia coli O157:H7 and
salmonella, and a preparation method. The formula of the culture medium comprises the following components of, in parts by weight, 15.0-19.0 parts of
tryptone, 2.7-3.3 parts of peptone, 5.5-6.5 parts of
yeast extract, 4.5-5.5 parts of
sodium chloride, 2.25-2.75 parts of
dipotassium phosphate, 8.6-10.6 parts of
disodium hydrogen phosphate, 1.22-1.48 parts of
potassium dihydrogen
phosphate, 24.0-30.0 parts of peptone, 14.0-18.0 parts of beef
powder, 10.0-14.0 parts of soy peptone, 2.0-5.0 parts of glucose, 0.10-0.30 part of actinomycete
ketone, 2.5-3.5 parts of
mannitol, 4.5-6.5 parts of
sodium pyruvate, 0.00125-0.00300 part of
acridine yellow, 0.0007813-0.0032500 part of
fosfomycin sodium and 1000 parts of
distilled water, and the pH value of theculture medium is 6.8-7.4. The single enrichmenteffect of the composite
enrichment culture medium is superior to that of respective selective enrichment liquid, growth of non-target
bacteria can be well inhibited, under the condition that non-target
bacteria exist, the culture medium can further achieve constant-speed and rapid proliferation of the three target
bacteria.