Muller Kauffmann Tetrathionate Broth Base is used for enriching Salmonella from food and environmental samples prior to selective isolation.
Salmonellosis is one of the most important and most frequently reported human foodborne diseases worldwide.1 Outbreaks have been associated with the consumption of pork and pork
products,2,3 broiler chickens,4 and other animals. Environmental sources include animal feed, litter and dust from hen houses, and animal feces. The process of isolating Salmonella from food is often difficult. The key to successful recovery lies in obtaining the contaminated portion of test sample. Even when the contaminated material has been obtained, Salmonella may be present only in small numbers and accompanied by larger numbers of other contaminating bacteria. Pre-enrichment is necessary to permit the detection of low numbers of Salmonella or injured Salmonella. Following pre-enrichment, the selective enrichment step destroys most of the competing flora, allowing the Salmonella to be recovered. Muller5 recommended Tetrathionate Broth as a selective medium for the isolation of Salmonella. Kauffmann6 modified the formula to include oxbile and brilliant green as selective agents to suppress bacteria such as Proteus spp. Jeffries7 described the addition of novobiocin at 40 mg per liter of broth to further suppress the growth of Proteus sp. Muller Kauffmann Tetrathionate Broth Base is used for isolating Salmonella from food, environmental samples4,8-13 and animal feces.14 Using more than one selective broth increases the isolation of Salmonella from samples with
multiple serotypes.15
Muller Kauffmann Tetrathionate Broth Base contains peptone and beef extract as sources of carbon, nitrogen, vitamins and minerals. Oxgall and added brilliant green are selective agents
which inhibit gram-positive and other gram-negative organisms. Calcium carbonate is the buffering agent. Sodium thiosulfate is a source of sulfur.
Difco™ Muller Kauffmann Tetrathionate Broth Base
Approximate Formula* Per Liter
Beef Extract.................................................................. 5.0 g
Peptone..................................................................... 10.0 g
Sodium Chloride........................................................... 3.0 g
Calcium Carbonate...................................................... 45.0 g
Sodium Thiosulfate (anhydrous).................................... 38.1 g
Oxgall......................................................................... 4.7 g
*Adjusted and/or supplemented as required to meet performance criteria.
Identity Specifications
Muller Kauffmann Tetrathionate Broth Base
Dehydrated Appearance: Off-white to light beige, free-flowing, homogeneous.
Solution: 10.58% solution, insoluble in purified water.
Solution is very pale green with white precipitate.
Prepared Appearance: Very pale green with white precipitate.
Reaction of 10.58%
Solution, with additives,
at 25°C: pH 7.0 ± 0.2 (adjusted)
Cultural Response
Muller Kauffmann Tetrathionate Broth Base Prepare the medium per label directions, with the addition of 1.9 mL iodine solution and 0.95 mL brilliant green solution per 100 mL of medium.
Inoculate and incubate at 42-43°C for 18-24 hours. Subculture to Brilliant Green Agar and incubate at 35 ± 2°C for 18-24 hours.
ORGANISM | ATCC™ |
INOCULUM |
RECOVERY |
COLONY COLOR |
Escherichia coli | 25922 | 103-2×103 | None to poor | - |
Proteus vulgaris | 13315 | 103-2×103 | None to poor | - |
Salmonella enterica subsp. |
14028 | 100-300 | Good | Red |
Salmonella senftenberg |
100-300 | Good | Red |
1. Suspend 105.8 g of the powder in 1 L of purified water and boil gently.
2. Cool to below 45°C.
3. Add 19 mL of iodine solution (20 g iodine and 25 g potassium iodide in 100 mL water) and 9.5 mL brilliant green solution (0.1 g brilliant green in 100 mL water).
4. Adjust the pH of the complete medium to 7.0 ± 0.2 using 1N HCl.
5. Dispense into sterile tubes, mixing well to evenly disperse the calcium carbonate.
6. Test samples of the finished product for performance using stable, typical control cultures.
Refer to appropriate references for details on sample collection and preparation according to sample type and geographic location.4,8-13 Consult appropriate references for details on test methods using Muller Kauffmann Tetrathionate Broth.4,8-13
Salmonella spp. will produce red colonies with good growth.
1. The complete medium is unstable and should be used immediately. It may be stored at 2-8°C in the dark for no more than 7 days.
2. Due to the nutritional requirements and inhibitory characteristics of the organisms themselves, organisms other than salmonellae, such as Morganella morganii and some Enterobacteriaceae may grow in the medium.
3. Confirmatory tests, such as fermentation and seroagglutination reactions, should be carried out on all presumptive Salmonella colonies that are recovered.
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1. Baird Parker. 1990. The Lancet. 336:1231.
2. Van Pelt and Valkenburgh. 2001. Zoonoses and zoonotic agents in humans, food, animals and feed in the Netherlands.
3. Hald et al. 1999. 3rd International Symposium of the Epidemiology and Control of Salmonella in Pork, Washington, D.C. 197.
4. Proietti, Pedrazzoli, Bosco, Galli, Canali and Franciosini. 2006. Presented at the Twelfth European Poultry Conference, Verona, Italy, 10 to 14 Sept. 2006.
5. Muller. 1923. C. R. Soc. Biol. (Paris) 89:434.
6. Kauffmann. 1935. Ztschr. F. Hyg. 117:26.
7. Jeffries. 1959. J. Clin. Path. 12:568.
8. Public Health Laboratory Service. 1974. Monograph Series No. 8. Public Health Laboratory Service, London, England.
9. Detection of Salmonella from poultry neck skins. 29 Dec 2008.
10. Detection of Salmonella from minced meat, mechanically separated meat (MSM) and meat products. 29 Dec 2008.
11. Electronic Code of Federal Regulations (e-CFR), Title 9: Animals and Animal Products, Part 147– Auxiliary provisions on national poultry improvement plan. 23 Dec 2008.
12. Fablet, Fravalo, Jolly, Robinault and Madec. 2005. Int. Soc. Anim. Hyg. 2:273.
13. Health Protection Agency Standard Method. 2008. Method F13: Detection of Salmonella species. Standards Unit, Evaluations and Standards Laboratory, Centre for Infections, National Public Health Service for Wales.
14. Michael, Simoneti, DaCosta and Cardoso. 2003. Braz. J. Microbiol. 34:138.
15. Harvey and Price. 1976. J. Hyg. Camb. 77:333.