The Use of Bacterial Membrane Fractions for the Detection of Campylobacter Species in Shellfish

Abstract

Selected enrichment broths supplemented with the enzyme Oxyrase a membrane‐bound enzyme derived from E. coli were evaluated for recoveries of Campylobacter under normal atmospheric conditions from shellfish. Results indicate that Oxyrase is useful for the recovery of Campylobacter from shellfish. Effect of Oxyrase on growth of Campylobacter were dependent upon physical parameters such as media volume and surface volume area. For example, in the comparision of growth of Campylobacter sp (low to high levels, 1 × 101 to 6/mL) in various media volumes in Stomacher 400 closure bags and 250 mL and 500 mL screw‐capped Erlenmeyer flasks, no campylobacters were recovered using the closure bags. However, all levels of Campylobacter were recovered in the Erlenmeyer flasks. Oxyrase was useful for the recovery of C. jejuni from Pacific oysters (Crossostrea gigas). In one study, Pacific shellstock oysters were allowed to take up 1 × 106 cells of C. jejuni per mL for a period of 5 to 7 h in an artificial seawater aquarium system. Oysters were removed and stored at 4C for 24 days. Uptake in oysters ranged from 0.4 to 114 cells/g. At intervals, oysters were removed and analyzed for C. jejuni by using the Oxyrase method and the FDA/Bacteriological Analytical Manual standard method. Comparison of these methods showed that the Oxyrase method was as reliable as the official FDA method. Oxyrase was also useful for recovering naturally occurring Campylobacter in market oyster shellstock. To measure reproducibility of the method, an in‐house preliminary collaborative study was conducted in the University of Central Venezuela (Caracas). Participants consisted of 6 groups of three microbiologist each from various countries in Central and South America. All groups were successful in recovering Campylobacter jejuni and Campylobacter coli using Oxyrase. Our results indicate that Oxyrase provides microaerobic conditions for growth of Campylobacter from shellfish.

Campylobacter spp. as a Foodborne Pathogen: A Review

“…The incorporation of the enzyme Oxyrase in selective broths is particularly effective in reducing the levels of oxygen and improving the isolation of Campylobacter spp. from naturally contaminated samples (Abeyta et al, 1997 ). However, a blood free enrichment broth not requiring the addition of Oxyrase, nor special atmospheres has been tested and found to perform well against other more complex isolation methods (Tran, 1998 ).…”

Campylobacter in Poultry: Species Emergence, Pathogenesis and Antibiotic-Resistance Prevalence

“…The incorporation in broth medium, the enzyme Oxyrase is particularly effective in reducing the levels of oxygen or using different antibiotics in medium improving the isolation of Campylobacter spp. from naturally samples [24,25]. Many agar medium particularly Preston, Doyle and Roman, charchoal cefoperazone deoxycholate (CCDA), Butzler agars and CAT agar (Modified CCDA) [26], has been tested for isolating the Campylobacter from contaminated samples visible colonies usually appear on the plating media within 24-48h.…”