Abstract
In order to controlSalmonellacontamination in oil-meal manufacturing plants, the random amplified polymorphic DNA method (RAPD), used routinely for the epidemiological investigation of contamination, was examined.
In the evaluation, the degree of clarity of bands in the RAPD electrophoresis changed depending on the DNA extraction method, culture concentration and kinds of primer. Of the three kinds of DNA extraction methods, the NaI method showed the highest degree of clarity regardless of the culture concentration and the kinds of primer. The Boil-NaI method that we modified in this examination also showed stable bands with a high degree of clarity for all of the primers examined. In contrast, in the Boil method, the higher the culture concentration was, the lower the band clarity.
Forty-six strains (10 serovars) ofSalmonellaisolated from the environment of different oil-meal manufacturing plants and materials for oil meal were evaluated to determine their discriminatory power using 16 kinds of primers which are frequently used for outbreaks of S. Enteritidis. Of the 16 kinds of primers, AP47, OPB17 and AP46showed a high discriminatory power and the discriminatory percentages were 67.4, 60.9 and 58.7%, respectively. When these three primers were used together, the discriminatory percentage increased to 89.1%.
From the results mentioned above, the Boil-NaI modified method using these three primers has been shown to be an effective method for routine contamination investigations, because the modified method takes only 8 hours from DNA extraction to the examination of RAPD electrophoresis patterns.
