Enumeration of Vibrio parahaemolyticus and Vibrio vulnificus in Various Seafoods with Two Enrichment Broths

Abstract

This study compares recoveries of Vibrio parahaemolyticus and Vibrio vulnificus with salt-polymyxin B broth (SPB) and alkaline peptone water (APW) from samples of crab legs, oysters, shrimp, lobster and shark, which were inoculated at three levels (approximately 101 to 102, 102 to 103 and 104 to 105/g) with each of the pathogens. Six samples of each product were analyzed [3-tube most probable number (MPN)] with each broth. Inoculated samples of oysters and slurries of crab and lobster were also tested after cold stress (refrigerated at 2 to 4°C, 3 or 7 days, or frozen at −15°C for 21 or 28 days). For each seafood, geometric means of cells recovered with APW were significantly (P < 0.05) higher than the corresponding means of recovery with SPB. In addition, 12 of 15 calculated estimates of 50% relative detectable levels (RDL50) were lower (P < 0.05) for APW than for SPB. In these samples, the level of detection by APW was found to be 40 to 32,000 and 6- to 42-fold lower for V parahaemolyticus and V. vulnificus, respectively, than the level of detection by SPB. In cold-stored samples, overall detection of the pathogens was greatly reduced, but APW was also more efficient than SPB in recovering stressed cells.

Updated perspectives on emerging vibrios associated with human infections

“…Many species of Vibrio may be isolated with different solid media such us cellobiose polymyxin B colistin (CPC), blood agar flooded with oxidase reagent after incubation, or mannitol–maltose agar (Hagen et al. 1994; Donovan and van Netten 1995).…”

“…Many species of Vibrio may be isolated with different solid media such us cellobiose polymyxin B colistin (CPC), blood agar flooded with oxidase reagent after incubation, or mannitol-maltose agar (Hagen et al 1994;Donovan and van Netten 1995). The FDA procedure includes the evaluation of V. parahaemolyticus pathogenicity by detection of the Kanagawa phenomenon using Wagatsuma agar, containing high-salt blood to detect the haemolytic activity of V. parahaemolyticus thermostable direct haemolysin (TDH)-positive strains only.…”

A review of the current status of cultural and rapid detection of Vibrio parahaemolyticus

“…To counteract for these phenomena, a plethora of alternative enrichment broths and plating media have been developed (Oliver, 1981; Oliver et al. , 1992; Hagen et al. , 1994; Azanza et al.…”

“…For example, Hara-Kudo et al (2001) observed that when seafood was evaluated for the presence of V. parahaemolyticus, colonies on TCBS agar were difficult to distinguish visually from other bacterial colonies because of the presence of a yellow pigment produced by sucrose fermenting bacteria. To counteract for these phenomena, a plethora of alternative enrichment broths and plating media have been developed (Oliver, 1981;Oliver et al, 1992;Hagen et al, 1994;Azanza et al, 1996;Høi et al, 1998a,b;Cerda´-Cue´llar et al, 2000;Alam et al, 2001). For example, CHROMagarÔ Vibrio is a differential medium that represents an alternative to TCBS.…”

Vibrio parahaemolyticus produtores de urease isolados a partir de ostras (Crassostrea rizophorae) coletadas in natura em restaurantes e mexilhões (Perna perna) de banco natural

“…A proporção de cepas produtoras de gastrenterite varia de acordo com as condições geográ-ficas e sazonais, portanto a freqüência de isolamento é maior, nos meses de verão, quando podem ocorrer surtos ou casos esporádicos de gastrenterite, após consumo de água ou alimentos marinhos contaminados [8,9,12,15,23,30].…”