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Isolation of Plesiomonas shigelloides from Oysters Using Tetrathionate Broth Enrichment 1
Susan M Freund1, John A Koburger1, Cheng-I Wei1
1Food Science and Human Nutrition Department, University of Florida, Gainesville, FL 32611.
Abstract:
In a study to compare five enrichment broths for enhancing the recovery of Plesiomonas shigelloides from water samples, tetrathionate broth without the addition of iodine exhibited better (P<0.05) recovery of this microorganism than did alkaline peptone water, gram negative broth, plesiomonas enrichment broth (PLE), a modified PLE, or direct plating. The established enrichment parameters were applied to test raw packaged and freshly shucked oyster meats, as well as bacterial mixtures. The enrichment process enhanced the detection of P. shigelloides in a Plesiomonas-Klebsiella mixture but not in a Plesiomonas-Pseudomonas mixture. Recovery of P. shigelloides in oyster samples was found to be affected by both the number and type of competing bacteria present as well as incubation temperature used for enrichment.
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