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KM0079 Pseudomonas Agar Base with the addition of supplements, is a selective medium for the isolation of Pseudomonas species primarily from clinical, food, water, and environmental samples. The medium can be made selective for Pseudomonas aeruginosa by the addition of E&O LS0006 Pseudomonas Selective Cetrimide and Nalidixic Acid Supplement which complies to ISO 16266:2006 and ISO 11133:2014. Alternatively, the medium can be made selective for Pseudomonas species by the addition of E&O LS0026 Pseudomonas CFC Selective Supplement which complies to ISO 13720:2010 and can be used as a primary isolation medium according to Public Health England’s UK Standards for Microbiology Investigations. Identification is achieved using the unique ability of P. aeruginosa to synthesise the iron chelating pigments pyoverdin and pyocyanin which combine to produce the characteristic green colonies of Pseudomonas aeruginosa. Production of these pigments is stimulated by the presence of magnesium and potassium ions in the medium. The presence of blue/green or brown pigmentation or fluorescence is indicative of presumptive Pseudomonas species. It should be noted however that further testing must be conducted to confirm the full identity of the organism. -
R2A agar is used for the enumeration and cultivation of bacteria from drinking water. R2A agar developed by Reasoner and Geldreich is a low nutrient medium that can used in pour plate, spread plate, and membrane filtration methods for heterotrophic plate counts. In combination with a lower incubation temperature and longer incubation period R2A agar stimulates the growth of stressed and chlorine-tolerant bacteria. Traditionally nutritionally rich media have been used for this purpose but these media support the growth of fast-growing bacteria and may suppress slow growing or stressed bacteria found in treated water. Enzymatic digest of casein, proteose peptone, acid hydrolysate of casein and yeast extract provide the required nitrogen, carbon and vitamins. Glucose is a fermentable carbohydrate. Dipotassium hydrogen phosphate is a buffering agent. Magnesium sulphate is a source of divalent cations and sulphate. Starch and sodium pyruvate aid in the recovery of stressed organisms.
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Rappaport-Vassiliadis (MSRV) Medium Semi-Solid is a modification of Rappaport-Vassiliadis Soy Broth for detecting motile Salmonella spp. in faeces and food products.[1] The original research on MSRV Medium revealed a semi-solid could be used as a rapid and sensitive test for isolating motile Salmonella spp. from food products following pre-enrichment or selective enrichment.[2] The semi-solid medium allows motility to be detected as halos of turbid growth around the original point of inoculation. The peptones are to provide vitamins, nutrients and nitrogen to encourage growth of Salmonella spp. The salt maintains the osmotic balance and potassium dihydrogen phosphate is a buffer for stabilising the pH of the medium. Malachite green is included as a selective agent that inhibits Gram-positive organisms and some Gram-negative organisms. References (1) ISO 6579-1:2017. Microbiology of the food chain – Horizontal method for the detection, enumeration and serotyping of Salmonella – Part 1: Detection of Salmonella spp. (2) De Smedt J.M., Bolderdikj R., Rappold H. and Lautenschlaeger D. 1986. Rapid Salmonella Detection in Foods by Motility Enrichment on a Modified Semi-Solid Rappaport-Vassiliadis Medium. J. Food Prot. 49:510-514
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Rappaport-Vassiliadis Soya Broth is used for the enrichment and selective isolation of Salmonella spp. This medium is a modification of the original formulation by Rappaport et al. and has been formulated to exploit the full characteristics of Salmonella spp. These characteristics include the ability to survive at relatively high osmotic pressure, to multiply at low pH values and greater resistance to malachite green. This formulation also has the correct amount of magnesium chloride as previous formulations did not take into account the volume of displacement caused by dissolving large amounts of magnesium chloride in water. This formulation has been shown to be superior to tetrathionate broth and selenite broth for the isolation of Salmonella spp. from meat products. Soya peptone provides the required carbon, nitrogen and vitamins. Potassium dihydrogen phosphate and di-potassium hydrogen phosphate act as buffers. Magnesium chloride raises the osmotic pressure in the medium. Malachite green is an inhibitory substance. NB: This formulation is very hygroscopic and will produce a slight exothermic reaction when mixed with water.
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KM0003 Sabouraud Dextrose Agar powder is a general-purpose, non-selective medium which is used for the isolation of yeasts and moulds from clinical, food, pharmaceutical and cosmetic samples. Sabouraud Dextrose Agar is a modification of a medium originally described by Sabouraud. The fungi maintain their typical cultural appearance and thus may be readily identified according to the standard macroscopic characters described by Sabouraud. The formulation conforms to European, United States and Japanese Pharmacopeia requirements. This medium complies with ISO 11133:2014, where it is described as the main reference medium to carry out quantitative testing on culture media intended for fungi. Sabouraud Dextrose Agar is recommended by the UK Standards for Microbiology Investigations for various purposes, including as a standard, supplementary or optional medium. Related Supplements : LS0050 Chloramphenicol Selective Supplement
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Sabouraud dextrose agar with chloramphenicol is a selective media for the isolation of yeasts and fungi suitable for use in all areas of mycology. Sabouraud dextrose agar is a modification of a medium originally described by Sabouraud.(1) The tryptone and meat peptone provides the required nitrogen, carbon and vitamins. The high concentration of dextrose is included as an energy source and in tandem with the acidic pH (5.6) facilitates the growth of fungi whilst providing limited selective properties.(2) Chloramphenicol is included to increase the selectivity of the media inhibiting a range of Gram-positive and Gram-negative bacteria. References (1) Sabouraud, R. 1892. Ann. Dermatol. Syphilol. 3:1061. (2) Jarett, L., and A. C. Sonnenwirth (eds.). 1980. Gradwohl’s and parasitic infections, 7th ed. American Public Health Association, Washington, D.C.
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Sabouraud liquid medium USP is used in sterility testing for the detection of moulds, yeasts and acidophilic microorganisms in pharmaceutical products. This medium is also used for non-sterile testing and for the determination of fungistatic activity. Sabouraud liquid medium USP conforms to the USP and Harmonised Pharmacopeia. The peptic digest of animal tissue and pancreatic digest of casein provides the required nitrogen, carbon and vitamins. The high concentration of dextrose is included as an energy source and in tandem with the acidic pH (5.6) facilitates the growth of fungi whilst providing limited selective properties.
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This is a selective medium for the isolation of Salmonella spp. and Shigella spp. from clinical specimens and food samples. SS agar is a modification of the original DCA medium described by Leifson. The formulation for SS agar was later modified to improve the growth of Shigella spp. SS agar modified differs from SS agar in that it has an alternation to the bile salts mixture, peptone, pH value, and total g/litre. The peptone provides the required carbon, nitrogen and vitamins. Lactose is a fermentable carbohydrate and neutral red is a pH indicator. Sodium thiosulphate and ferric citrate are used to detect hydrogen sulphide production indicated by the black centred colonies of hydrogen sulphite positive organisms. Bile salts, sodium citrate and brilliant green inhibit Gram-positive bacteria and a number of different coliform bacteria.
