EFFECT OF DILUTION, INCUBATION-TIME, AND TEMPERATURE OF ENRICHMENT ONCULTURAL AND PCR DETECTION OF VIBRIO-CHOLERAE OBTAINED FROM THE OYSTER CRASSOSTREA-VIRGINICA

The recovery of Vibrio cholerae O1 by culture from the oyster Crassost rea virginica and detection of the cholera toxin gene by polymerase ch ain reaction were evaluated using various enrichment procedures in alk aline peptone water. The effects of dilutions (1:10 and 1:100), incuba tion times (6-8 and 18-21 h), and incubation-temperatures (35 and 42 d egrees C) were determined. Recovery of V. cholerae was significantly g reater (P<0.05) from oyster homogenates diluted 1:100 in alkaline pept one water and incubated at 42 degrees C for 18-21 h. This enrichment p rocedure also provided the best detection of the cholera toxin gene by polymerase chain reaction.