EFFECT OF OXYGEN REDUCING MEMBRANE FRAGMENTS ON GROWTH OF CAMPYLOBACTER SPP. 1

Self Cite

Supplementation of Niroomand and Fung broth (NFB) and Hunt broth (HB) with Oxyrase®, sheep blood, hemin or yeast extract for recovery of Campylobacter was evaluated. Five strains of C. jejuni and one strain of C. coli were cultured in HB with or without Oxyrase®, NFB with or without Oxyrase®, NFB without hemin, and NFB plus yeast extract without hemin. The HB without Oxyrase® was evacuated and flushed three times with mixed gas (5% O2, 10% CO2, and 85% N2) prior to incubation. The effect of blood in HB supplemented with Oxyrase® on the growth of Campylobacter was also examined. Hunt broth showed significantly better performance than NFB (p<0.05). Supplementation of 0.2% hemin and 0.6% yeast extract stimulated growth by up to 2 log CFU/mL depending on strains. Addition of 7% lysed blood enhanced growth of C. jejuni, and differences were significant at 6 h and 24 h of incubation. At 20 h of incubation, broth containing 0.6 units/mL of Oxyrase® yielded Campylobacter counts of 8.6 to 10.9 log CFU/mL, and the broth flushed with mixed gas provided counts of 9.4 to 11.0 log CFU/mL. No statistical difference (p>0.05) was found between the Oxyrase® method and gas replacement method at incubation times of 12h, 20h, 28h, and 36h for all strains tested. Dissolved oxygen levels of all enrichment media were less than 1.5 mg/L. Using Oxyrase® supplemented HB without the cumbersome gassing step provides a simple and time‐saving procedure for culturing Campylobacter jejuni and C. coli.

“…(2) Niroomand and Fung (NF) broth was prepared according to their formulation (Niroomand and Fung 1994). Brucella broth (Difco) was prepared according to the manufacturer's procedure.…”

Section: Preparation Of Enrichment Mediamentioning

confidence: 99%

EFFECT OF SUPPLEMENTS ON CAMPYLOBACTER GROWTH IN ENRICHMENT MEDIA¹

Wonglumsom

Fung

2001

Self Cite

“…(Unipath Co., Oxoid Division, Columbia, MD) (George et d. 1978), and 1.0 ml of Campylobacter selective supplement (Skirrow) (Unipath Co., Oxoid Division, Columbia, MD) were added to complete the formulation of the 5X brucella enrichment broth. For oxyrase supplemented 5X brucella enrichment broth, a 5 ml portion of oxyrase enzyme (EC-102,30 unitslml, Oxyrase Inc., Ashland, OH) (Niroomand and Fung 1994) was then added. The culture tubes were gently tapped at the bottom to mix well but avoid excess aeration and the caps were then closed tightly.…”

Section: Sampling and Enrichment Of Samplesmentioning

confidence: 99%

FLUORESCENCE CONCENTRATION IMMUNOASSAY FOR RAPID DETECTION OF CAMPYLOBACTER SPP. IN CHICKEN RINSE WATER

Tsai

Slavik

1994

A total of 215 freshly processed post‐chill whole chicken carcasses were assessed for Campylobacter spp. contamination by a fluorescence concentration immunoassay (FCIA) procedure. Whole chicken carcasses were sampled with low volume water rinses from which 5 ml portions were enriched with brucella enrichment broth with or without oxyrase supplement in a test tube enrichment system. After a 24h stationary incubation at 42C, each sample was assayed using a FCIA procedure for the presence or absence of campylobacters. The FCIA procedure indicated Campylobacter spp. contamination in 84% of carcasses using oxyrase supplemented enrichment, while only 47% of the chicken carcasses were positive from nonsupplemented enrichment. The corresponding incidence rates detected by culture method were 92% and 87% for oxyrase supplemented and unsupplemented samples, respectively. The FCIA procedure can be completed in less than 1 h with 48 samples including a positive and a negative control assayed on one plate. In summary, the test tube oxyrase‐supplemented stationary enrichment system followed by the use of the FCIA procedure was found to be an effective, rapid method for the detection of Campylobacter spp. in chicken rinse water.

“…One unit of activity reduces 1% of the initially dissolved oxygen per second per milliliter. OxyraseTM has been used to successfully culture many anaerobes and facultative anaerobes without adjustment of atmospheric conditions, and has also been used to promote the growth of microaerophiles such as Carnpylobacter and Arcobacter (Niroomand and Fung 1994;Liu et aZ. 1996).…”

Section: Introductionmentioning

confidence: 99%

EFFECT OF AN OXYGEN‐REDUCING MEMBRANE FRACTION ON HELICOBACTER PYLORI

Cohen

Hirshfield

1997

l2e emerging gastric pathogen Helicobacter pylori is an oxygen-sensitive fastidious microaerophile. Culturability of this organism is rapidly lost in oxygen levels present in the atmosphere due to its morphological transformation into a viable but not culturable state. l2e effect of the Oxyrasem system of oxygenreducing membrane fragments on H. pylori was evaluated at levels ranging from 0.1 to 0.6 Units/mL in Brucella broth supplemented with 5 % horse serum.Duplicate sets of Oxyrasem dilutions inoculated with H . pylori were incubated at 35C aerobically and microaerobically. At these Oxyrasem levels, a logarithmic loss of H. pylori viability was evident in the aerobic cultures. The inoculum remained recoverable for 24 h in the presence of OxyraseTu, whereas recovery of inoculum in untreated broth was greatly reduced afer 8 h of aerobic incubation, and the organism was unrecoverable afer 24 h. Oxyrasem-containing broth cultures of H . pylori incubated microaerobically showed a similar drop in viable counts for the$rst 48 h of incubation; however, at the lower levels of Oxyrasem, some cells survived, and resumed logarithmic growth at 96 h. To explore the effects of short term aerobic incubation in the presence of 0, 0.005, 0.05, and 0.5 Units Oxyrasem, cultures were exmined microscopically afrer 4, 8, and 24 h. In the OxyraseTM-containing broths, <90% of the cells exhibited rod shape morphology after 8 h, whereas in the untreated broth, most cells appeared coccoid. After 24 h, all cells exhibited coccoid morphology.