[Development of a rapid separating incubation method for detection of Escherichia coli O157:H7 in food].
To detect Escherichia coli O157:H7 in food, a selective and differential medium, CTV-MUG-RSMAC agar, was designed. Using this medium, the growth of most interfering organisms could be inhibited, and three main biochemical characteristics, including sorbitol-negative, rahmnose-negative and MUG-negative, to identify E. coli O157:H7 could also be simultaneously recognized. Sorbitol-positive aberrance strains of E. coli O157:H7 could be distinguished on the medium. The procedure of detecting food sample includes adding sample to selective broth and incubating overnight at 42 degrees C, streaking the inoculum to CTV-MUG-RSMAC agar and incubating at 37 degrees C for 24 h, and picking the typical colonies to react with sera for O157 and H7 antigens, and then take biochemical tests. The procedure could be finished within 3 days. This method has been applied to 126 food samples, and E. coli O157:H7 was detected from 3 samples. The results were in coincidence with those using FDA method.
Wang
Jing
J
China Import & Export Commodity Inspect Technology Institute, Beijing 100025, China.
Qiu
Maofeng
M
Lin
Xiuguang
X
D000818:Animals; D002417:Cattle; D019453:Escherichia coli O157 / Q000302:isolation & purification*; D005396:Fish Products / Q000382:microbiology*; D008460:Meat / Q000382:microbiology*; D008892:Milk / Q000382:microbiology; D013552:Swine