ICMSF methods studies. V. The influence of selective enrichment media and incubation temperatures on the detection of salmonellae in raw frozen meats

1974 ◽  
Vol 20 (6) ◽  
pp. 813-816 ◽  
Author(s):  
J. H. Silliker ◽  
D. A. Gabis
Keyword(s):  
Brilliant Green ◽  
Medium Temperature ◽  
Raw Meat ◽  
Selective Media ◽  
Selective Enrichment ◽  
Incubation Temperatures

Sixty lots of frozen raw meat were analyzed for Salmonella using preenrichment in lactose broth followed by selective enrichment in four different selective broths, each incubated at 35C and 43C. Incubation at 43C resulted in detection of more Salmonella-containing samples. The highest recovery was observed with selenite cystine at 43C. However, the data indicated that two selective broths should be used for maximum recovery. Tetrathionate broth without brilliant green was inferior to the three other selective media used, both at 35C and 43C. Using selenite cystine, tetrathionate brilliant green, and selenite brilliant green sulfa broths, a number of medium/temperature pairs gave Salmonella recoveries approaching that obtained from all eight medium/temperature variables combined.

ICMSF methods studies. IX. The influence of selective enrichment broths, differential planting media, and incubation temperatures on the detection of Salmonella in dried foods and feed ingredients

1977 ◽  
Vol 23 (9) ◽  
pp. 1225-1231 ◽  
Author(s):  
D. A. Gabis ◽  
J. H. Silliker
Keyword(s):  
Elevated Temperature ◽  
Brilliant Green ◽  
The Other ◽  
Feed Ingredients ◽  
Selective Media ◽  
Selective Enrichment ◽  
Enrichment Cultures ◽  
Incubation Temperatures ◽  
Better Than ◽  
Dried Foods

Ninety-eight dried foods and feed ingredients were analyzed for Salmonella using tetrathionate brilliant green (T) and selenite cystine (S) broths incubated at 35 and 43 °C. The four enrichment cultures for each sample were subcultured in duplicate onto brilliant green (BG), Salmonella–Shigella (SS), and bismuth sulfite (BS) agars, one plate of each being incubated at 35 °C, the other at 43 °C. Salmonellae were isolated from 44 of the 98 samples. Differences in the Salmonella recovery rates from the four selective enrichment conditions were not significant. However, there was a trend toward a higher proportion of Salmonella colonies on the selective media when the enrichment broths were incubated at 43 °C, although the differences were significant only with BG and SS subcultured from T. While the four enrichment systems were not significantly different, the trend toward a higher proportion of Salmonella colonies on the differential media subcultured from 43 °C enrichment broths indicates an advantage to incubation at the elevated temperature. Incubation of selective agars at 35 °C was best because at 43 °C Salmonella recovery was significantly reduced. Detection of salmonellae on BS was significantly better than on BG or SS.

Prevalence of Salmonella spp. and Yersinia enterocolitica in Finishing Swine at Canadian Abattoirs

1999 ◽  
Vol 62 (1) ◽  
pp. 22-25 ◽  
Author(s):  
ANN LETELLIER ◽  
S. MESSIER ◽  
S. QUESSY
Keyword(s):  
Confidence Interval ◽  
Yersinia Enterocolitica ◽  
Brilliant Green ◽  
Salmonella Spp ◽  
Selective Media ◽  
Selective Enrichment ◽  
Enrichment Technique

The prevalence of Salmonella spp. and Yersinia enterocolitica in finishing swine was evaluated using samples of cecal material. Samples were taken at six different slaughterhouses from 1420 healthy, 5-month-old pigs, raised by 223 producers in Québec (1009 samples), Ontario (283), and Manitoba, Canada (128). Two different broth media (Rappaport-Vassiliadis and Tetrathionate brilliant green) were used for the selective enrichment of Salmonella spp. The recovery of Y. enterocolitica was done by a cold enrichment technique, followed by plating on a selective media (cefsulodin-irgasan-novobiocin agar). Prevalence (with a 95% confidence interval) of Salmonella spp. and Y. enterocolitica were, respectively, 5.2% (4.0 to 6.4%) and 20.9% (18.8 to 23.0%). Overall, 24.6% of the animals tested were positive for one or both of these pathogens. Since only a few herds (2.8%) appeared to be highly contaminated by Salmonella spp., efforts should be undertaken in priority to control this pathogen in those herds.

ICMSF methods studies. VI. The influence of selective enrichment media and incubation temperatures on the detection of Salmonella in dried foods and feeds

1974 ◽  
Vol 20 (11) ◽  
pp. 1509-1511 ◽  
Author(s):  
D. A. Gabis ◽  
J. H. Silliker
Keyword(s):  
Brilliant Green ◽  
Selective Enrichment ◽  
Significant Difference ◽  
Low Moisture Foods ◽  
Incubation Temperatures ◽  
Red Meats ◽  
Enrichment Condition ◽  
By Products ◽  
Dried Foods

Recovery of Salmonella from low-moisture foods was studied using selective enrichment in tetrathionate brilliant green and selenite-cystine broths at 35C and 43C. A total of 1375 samples of dried dairy, soya, and rendered animal by-products were analyzed. All samples were preenriched before selective enrichment. No significant difference in recovery was detected between tetrathionate brilliant green and selenite cystine at either temperature, which is in contrast to our earlier findings with red meats. Pairing of enrichment conditions resulted in the detection of more positive samples than the use of any single enrichment condition.

Recovery of Salmonella from Fluid Milk

1988 ◽  
Vol 51 (5) ◽  
pp. 409-411 ◽  
Author(s):  
CLYDE R. WILSON ◽  
WALLACE H. ANDREWS ◽  
PAUL L. POELMA ◽  
VERNEAL R. BRUCE
Keyword(s):  
Brilliant Green ◽  
Incubation Temperature ◽  
Skim Milk ◽  
Selective Enrichment ◽  
Whole Milk ◽  
Peptone Water ◽  
Incubation Temperatures ◽  
Fluid Milk

Methodology was developed for isolation of Salmonella from skim milk, 2% fat milk, whole milk and buttermilk. Lactose broth, lactose broth plus brilliant green dye, buffered peptone water and each milk type plus brilliant green dye were evaluated as preenrichment broths. Incubation temperatures of 35 and 43°C were compared for use at the preenrichment stage. The recovery of Salmonella was determined after selective enrichment in selenite cystine, tetrathionate and Rappaport-Vassiliadis broths. Results indicated that fluid milk should be examined for Salmonella by being preenriched in lactose broth, subcultured to selenite cystine and tetrathionate broths and streaked to selective agars, with 35°C as the incubation temperature throughout the analysis.

Use of gene probes for the detection of quiescent enteric bacteria in marine and fresh waters

1995 ◽  
Vol 31 (5-6) ◽  
pp. 291-298
Author(s):  
Sally A. Anderson ◽  
Gillian D. Lewis ◽  
Michael N. Pearson
Keyword(s):  
Membrane Filtration ◽  
Enteric Bacteria ◽  
Probe Method ◽  
Detection Methods ◽  
23S Rrna ◽  
Specific Gene ◽  
Gene Probe ◽  
Selective Media ◽  
Selective Enrichment ◽  
E Coli

Specific gene probe detection methods that utilise a non-selective culturing step were tested for the ability to recognise the presence of quiescent enteric bacteria (Escherichia coli and Enterococcus faecalis ) within illuminated freshwater and seawater microcosms. An E. coli specific uidA gene probe and a 23S rRNA oligonucleotide probe for Enterococci were compared with recoveries using membrane filtration and incubation on selective media (mTEC and mE respectively). From these microcosm experiments a greater initial detection (from 4 hours to 1 day) of E. coli and Ent. faecalis using gene probe methods was observed. Additionally, a comparison of E. coli direct viable counts (DVC) in sunlight exposed microcosms with recoveries by selective media and gene probe methods revealed a large number of viable non-culturable cells. This suggests that enumeration of E. coli by a gene probe method is limited by the replication of the bacteria during the initial non-selective enrichment step. The detection of stressed Ent. faecalis by the oligonucleotide gene probe method was significantly greater than recovery on selective mE agar, indicating an Enterococci non-growth phase.

Preenrichment Conditions for Effective Recovery of Salmonella in Foods and Feed Ingredients

1979 ◽  
Vol 42 (2) ◽  
pp. 153-157 ◽  
Author(s):  
J. Y. D'AOUST ◽  
C. MAISHMENT
Keyword(s):  
Brilliant Green ◽  
False Negative ◽  
Food Samples ◽  
Contamination Level ◽  
Experimental Conditions ◽  
Feed Ingredients ◽  
Selective Enrichment ◽  
Negative Results ◽  
False Negative Results ◽  
The Cost

The efficacy of Clausen, EE, Eugon, GN, Tergitol 7, lactose and nutrient broths as Salmonella preenrichment media was evaluated using 165 food samples with an incident contamination level ranging from 1.5 to 460 salmonellae/100 g. Replicate food samples (100 g) were preenriched in each of seven media (900 ml) for 6 h and 24 h at 35 C; various amounts (10, 1.0 and 0.1 ml) of preenriched cultures were selectively enriched in tetrathionate brilliant green (43 C) and selenite cystine (35 C) broths and plated on bismuth sulfite and brilliant green sulfa agars. Short (6 h) and 24-h preenrichment conditions resulted in 26 (16%) and 8 (5%) false negative results, respectively. Recovery of Salmonella from 6-h but not 24-h preenrichment cultures also varied directly with the portion of culture inoculated into selective enrichment broths. None of the preenrichment media tested performed satisfactorily at 6 h of incubation where levels of recovery ranged from 32 to 62%; at 24 h, good recovery was obtained with all media (95 to 100%) except EE broth (74%). The incidence of competitive flora was significantly higher on selenite + brilliant green sulfa than on tetrathionate + bismuth sulfite; transfer volumes (10 and 1.0 ml) and preenrichment media did not contribute significantly to the presence of non-salmonellae on plating media. Characteristics of preenrichment media were found to be less critical than preenrichment incubation time for effective recovery of Salmonella in foods and feed ingredients. The use of 1.0- rather than 10-ml preenrichment transfer volume is indicated because it proved to be completely reliable under our experimental conditions and reduced the cost of analyses.

Limited Sensitivity of Short (6 h) Selective Enrichment for Detection of Foodborne Salmonella

1990 ◽  
Vol 53 (7) ◽  
pp. 562-565 ◽  
Author(s):  
J.-Y D'AOUST ◽  
A. SEWELL ◽  
A. JEAN
Keyword(s):  
Brilliant Green ◽  
High Moisture ◽  
Selective Enrichment ◽  
Under Five ◽  
Analytical Protocol ◽  
Quantitative Analyses ◽  
Low Moisture Foods ◽  
Limited Sensitivity

Short (6 h) enrichment under five different selective conditions adversely affected the isolation of Salmonella from pre-enriched samples of naturally contaminated foods. Of the 109 high moisture and 18 low moisture foods found to contain salmonellae following conventional (24 h) enrichment, combined results of the abbreviated enrichment procedures identified only 99 (90.8%) and 13 (72.2%) contaminated samples, respectively. The productivities of tetrathionate brilliant green (TBG43) and Muller-Kauffman tetrathionate (MKTBG43) broths consistently exceeded that obtained with the modified Rappaport (RV43), tetrathionate brilliant green (TBG35), and selenite cystine (SC35) media after 6 and 24 h of incubation. Semi-quantitative analyses of growth under all enrichment conditions indicated that short (6 h) enrichment negatively affected method sensitivity through reduced numbers of Salmonella colonies and heavy growth of nonsalmonellae on bismuth sulfite (BSA) and brilliant green sulfa (BGS) plating media. These findings raise concerns on the dependability of commercial diagnostic schemes that incorporate abbreviated (6 h) enrichment in TBG35 and/or SC35 in their analytical protocol.

ICMSF methods studies. IV. International collaborative assay for the detection of Salmonella in raw meat

1974 ◽  
Vol 20 (5) ◽  
pp. 715-720 ◽  
Author(s):  
I. E. Erdman
Keyword(s):  
Significant Role ◽  
False Positive ◽  
Brilliant Green ◽  
Enrichment Broth ◽  
Raw Meat ◽  
Enrichment Medium ◽  
Significant Difference ◽  
International Collaborative ◽  
Raw Meats

An international collaborative assay of methods for the isolation of Salmonella from raw meats showed that more positive samples were identified when enrichment broth was incubated at 43C than at 35C. The choice of enrichment broth appears to be influenced by the serotype involved. Selenite brilliant green sulfa broth was the best enrichment medium for S. schwartzengrund, S. typhimurium, and S. dublin while selenite cystine broth was best for S. senftenberg. With S. newport and S. worthington no significant difference between tetrathionate broth and selenite brilliant green sulfa broth was apparent. While bismuth sulfite agar was successful for isolations from positive samples, it gave a large number of false-positive isolates when used with Salmonella-negative samples. This did not happen with the brilliant green agars used. Best results from selective agars were obtained when laboratories were allowed to choose their own, indicating that familiarity with a medium plays a significant role in its suitability for the isolation of Salmonella.

Modified Procedure to Inoculate Micro-ID

1980 ◽  
Vol 43 (10) ◽  
pp. 774-777 ◽  
Author(s):  
N. A. COX ◽  
J. S. BAILEY ◽  
J. E. THOMSON ◽  
M. O. CARSON ◽  
D. A. POSEY ◽  
...  
Keyword(s):  
Mixed Culture ◽  
Brilliant Green ◽  
Correct Identification ◽  
Selective Media ◽  
Inoculation Procedure ◽  
Selective Plating ◽  
Made In

The accuracy of a miniaturized Enterobacteriaceae system (Micro-ID) was evaluated with 10 different genera grown on 11 selective plating media. Whenever growth occurred, the correct identification was made. In addition, 12 serotypes of Salmonella and 22 other strains of Enterobacteriaceae were grown on the two most common selective media used by food microbiologists for isolation of Salmonella [Brilliant Green Sulfa Agar (BGS) and Bismuth Sulfite Agar (BiS)]. The correct identification was made in all instances. The manufacturer of Micro-ID originally recommended that several colonies be picked for inoculation of the system. We modified the inoculation procedure so that only one colony was selected from a plate; this minimized the chances of having a mixed-culture inoculum. With this procedure, all 21 Enterobacteriaceae tested were correctly identified.

scholarly journals Evaluation of Culture Media for Selective Enrichment and Isolation of Salmonella in Seafood

2010 ◽  
Vol 93 (5) ◽  
pp. 1468-1471 ◽  
Author(s):  
Rakesh Kumar ◽  
Poothuvallil K Surendran ◽  
Nirmala Thampuran
Keyword(s):  
Brilliant Green ◽  
Culture Media ◽  
Performance Difference ◽  
Selective Isolation ◽  
Salmonella Spp ◽  
Selective Enrichment ◽  
Significant Difference ◽  
Agar Media ◽  
Isolation Media

Abstract Seafood, including fish, shrimp, clam, crab, mussel, oyster, lobster, squid, octopus, and cuttlefish samples, was used to compare the recovery of Salmonella serovars by different selective enrichment and isolation media. The samples were selectively enriched in Rappaport-Vassiliadis (RV) broth and tetrathionate broth (TT), followed by selective isolation on Hektoen enteric (HE) agar, xylose lysine desoxycholate (XLD) agar, bismuth sulfite (BS) agar, and Brilliant Green (BG) agar media. Of 443 seafood samples analyzed, 108 were found to be contaminated with Salmonella. The role of selective enrichment in Salmonella spp. recovery with RV medium was distinctly high (70%) compared to TT broth (30%). The selective enrichment in RV broth followed by selective isolation on XLD, HE, BS, and BG agar recovered Salmonella at levels of 56, 41, 28, and 16%, respectively. Similarly, after enrichment in TT broth, XLD and HE agars recovered 27 and 23 respectively. The recovery of Salmonella with enrichment in TT followed by isolation on BS and BG was abysmally low at 4.6 and 5, respectively. There was no significant difference (P > 0.05) in the recovery of Salmonella using the combinations of XLD and HE media with selective enrichment in RV broth. However, performance difference (P <0.05) was observed in the recovery when BS and BG with RV, and XLD, HE, BS, and BG agars with TT broth were used. The present study showed that the combination of RV with XLD was the most efficient media for isolation of Salmonella from seafood when compared to other isolation media combinations.

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