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Malt extract broth is used for the cultivation of yeasts and moulds and is commonly used as part of sterility testing protocols. The high carbohydrate content of the medium ensures rapid growth of yeasts and moulds. Malt extract and mycological peptone provide the carbon, protein and nutrient sources required by the organisms. The acidic nature of this medium allows for optimal growth of moulds and yeasts while restricting bacterial growth. -
KM0031 Mannitol Salt Agar is a selective medium for the isolation of Staphylococcus aureus from clinical samples, food, cosmetics and water samples. Chapman showed that adding a higher level of sodium chloride to Mannitol Salt Agar allowed for the recovery of pathogenic staphylococci and inhibits most organisms. Coagulase positive staphylococci (e.g., S. aureus) produce yellow colonies and a surrounding yellow medium while coagulase negative staphylococci produce red colonies and no colour change of the phenol red indicator. The medium conforms to the requirements of the Harmonised EP/USP/JP, is recommended as a primary isolation media by the UK Standards for Microbiology Investigations and tested in accordance with ISO 11133:2014 and Clinical and Laboratory Standards Institute. This medium is also included in the Bacteriological Analytical Manual for cosmetics testing.
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Marine agar is a medium used to support the growth of numerous marine bacteria. Originally formulation by ZoBell (1), its high saline levels are to simulate a close approximation of seawater which allows the marine bacteria to grow (2). The sodium chloride and marine minerals provide the high salinity needed for marine bacteria to thrive and aims to simulate sea water. The peptones provide the necessary nitrogen, amino acids and vitamins for growth. Agar is the solidifying agent. References (1) ZoBell, C.E. 1941. Studies on Marine Bacteria. I. The cultural requirements of heterotrophic aerobes. J. Mar. Res. 4, 42-75. (2) Lyman, J. and Fleming, R. H. 1940. Composition of Seawater. J. Mar. Res. 3, 134-146
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Formulated to ISO 6887-1, Maximum Recovery Diluent (MRD) is a diluent designed to maintain organisms by protecting the cells from unnecessary physiological shock that may occur using other aqueous solutions. MRD is used extensively in food and environmental testing. The low level of peptone provides a protective effect but does not allow for multiplication during the short residence time in the diluent, 45 minutes. The sodium chloride prevents osmotic shock as the sample is initially diluted.
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Meat peptone is sourced from hydrolyzed proteins of animal tissue. This peptone consists of soluble amino acids and peptides that provide readily available nitrogen and other essential growth factors. It is primarily used for the cultivation of fastidious and non-fastidious microorganisms in microbiological culture media.
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Membrane Lauryl Sulphate Agar is used for the enumeration of Escherichia coli and other coliforms found in filter membranes used in water sample testing. The broth base, originally named Membrane Enriched Teepol broth,(1) was updated when Teepol 610 was removed from the formulation and replaced by sodium lauryl sulphate.(2&3) The peptones, yeast extract and lactose act as carbon, nitrogen and vitamin sources in this medium. The phenol red is added as a pH indicator to detect the fermentation of lactose to differentiate the coliforms. Sodium lauryl sulphate is an inhibitory agent. References (1) Burman, N. P., 1967. Development of membrane filter techniques. II. Adaptation to routine and special requirements. Proc. Soc. Wat. Treat. Exam., 16:40 (2) Joint Committee of PHLS and the Standing Committee of Analysis. 1980. J. Hyg. Camb., 85:181 (3) Stanfield, G. and Irving, T. E., 1981. A suitable replacement for Teepol 610 in the selective isolation of coliforms from marine waters and sewage. Water Research. 15:469-474
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Membrane Lauryl Sulphate Broth is used for the enumeration of Escherichia coli and other coliforms found in filter membranes used in water sample testing. Originally named Membrane Enriched Teepol broth,(1) this recipe was updated when Teepol 610 was removed from the formulation and replaced by sodium lauryl sulphate.(2&3) The peptones, yeast extract and lactose act as carbon, nitrogen and vitamin sources in this medium. The phenol red is added as a pH indicator to detect the fermentation of lactose to differentiate the coliforms. Sodium lauryl sulphate is an inhibitory agent. References (1) Burman, N. P., 1967. Development of membrane filter techniques. II. Adaptation to routine and special requirements. Proc. Soc. Wat. Treat. Exam., 16:40 (2) Joint Committee of PHLS and the Standing Committee of Analysis. 1980. J. Hyg. Camb., 85:181 (3) Stanfield, G. and Irving, T. E., 1981. A suitable replacement for Teepol 610 in the selective isolation of coliforms from marine waters and sewage. Water Research. 15:469-47
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Originally intended for enumeration of coliforms in water samples, a medium containing glutamic acid was devised by Folpmers and further developed by Gray as a potential replacement for MacConkey Broth. Later, Gray modified the medium to incorporate a variety of minerals promoting improved lactose fermentation by coliforms and Escherichia coli. Minerals Modified Glutamate Medium is suitable for the enrichment of low levels of coliforms and recovery of chlorine-damaged bacteria.
Minerals Modified Glutamate Medium is recommended by the Standing Committee of Analysts and International Organization for Standardization. It is tested in accordance with ISO 11133:2014.
