The occurrence of Bacillus cereus, B. thuringiensis and B. mycoides in Chinese pasteurized full fat milk.
In 2006, a total of 54 samples of pasteurized full fat milk packaged in cartons were collected in spring and in autumn from chain supermarkets in Wuhan, China. The samples were examined and enumerated by MPN methods strictly according to guidelines laid out in US FDA/CFSAN BAM Chapter 14. Among 102 isolated B. cereus-like bacteria, 92 isolates were identified to be B. cereus, 9 B. thuringiensis and 1 B. mycoides. It was found that the occurrences of B. cereus were 71.4% and 33.3% in spring and in autumn samples respectively and the average count among the positive samples was 11.7 MPN/ml. The PCR detection results revealed that the enterotoxin genes hblA, hblC, hblD, nheA, nheB and nheC occurred in B. cereus isolates with frequencies of 37.0%, 66.3%, 71.7%, 71.7%, 62.0% and 71.7% respectively. Nine B. thuringiensis isolates were also identified from six pasteurized milk samples, and most of them harbored six enterotoxic genes and the insecticidal toxin cry1A gene. The single B. mycoides isolate harbored nheA and nheC genes. The data provides information for further evaluating the effect of B. cereus-like bacteria on food safety of Chinese milk products.
Zhou
Guoping
G
State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
Liu
Haizhou
H
He
Jing
J
Yuan
Yongming
Y
Yuan
Zhiming
Z
D000818:Animals; D001407:Bacillus / Q000302:isolation & purification* / Q000472:pathogenicity; D001409:Bacillus cereus / Q000302:isolation & purification / Q000472:pathogenicity; D001413:Bacillus thuringiensis / Q000302:isolation & purification / Q000472:pathogenicity; D002681:China / Q000453:epidemiology; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D017931:DNA Primers; D004768:Enterotoxins / Q000235:genetics / Q000302:isolation & purification*; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods*; D006801:Humans; D008892:Milk / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D012621:Seasons; D013045:Species Specificity
D017931:DNA Primers; D004768:Enterotoxins