Dehydrated Culture Media

  • Luria Bertani (LB) agar (Miller) is used for the cultivation and maintenance of recombinant strains of Escherichia coli and is based on the formulation stated by Miller. This medium is typically used in molecular biology procedures such as the detection of phage or plasmid transformed bacteria. LB agar (Miller) is prepared using 10 g/L of sodium chloride and this level varies from that described by Lennox. Enzymatic digest of casein provides the required nitrogen and carbon for organism growth. Vitamin B complex required by recombinant strains of E. coli are supplied by the yeast extract. Sodium chloride maintains the osmotic balance and provides sodium ions for membrane transport. Related Supplements : LS0035 Ampicillin Selective Supplement, LS0037 Kanamycin Selective Supplement
  • Luria Bertani (LB) broth is used for the cultivation and maintenance of recombinant strains of Escherichia coli for molecular biology procedures. LB broth (Lennox) contains half of the amount of sodium chloride found in LB broth (Miller). Enzymatic digest of casein provides the required nitrogen and carbon. Vitamin B complex required by recombinant strains of Escherichia coli are supplied by yeast extract. Sodium chloride maintains the osmotic balance and provides sodium ions for membrane transport.
  • Luria Bertani (LB) broth is used for the cultivation and maintenance of recombinant strains of Escherichia coli for molecular biology procedures.(1) Enzymatic digest of casein provides the required nitrogen and carbon. Vitamin B complex required by recombinant strains of Escherichia coli are supplied by yeast extract. Sodium chloride maintains the osmotic balance and provides sodium ions for membrane transport.
  • Legionella agar was designed for the isolation of Legionella spp. and is used primarily in water and environmental laboratories. Since Legionella spp. are fastidious organisms, the medium contains yeast extract as a source of nitrogen, carbon and vitamins. Charcoal is also included to neutralise growth-inhibiting substances and agar is the solidifying agent. The medium requires supplementation with ferric pyrophosphate as a source of iron, L-cysteine, an essential amino acid for the growth of Legionella spp. and α-ketoglutaric acid, which acts as a growth stimulant. ACES buffer/potassium hydroxide is also added to maintain the optimal pH of 6.9 for growth of Legionella spp. Omission of the L-cysteine produces a confirmation medium that can be used to test presumptive Legionella spp. as isolates will not be able to grow. Selective versions of the medium can also be created by the addition of various selective agents. GVPC is the most popular for water testing and BMPA for clinical testing. Related Supplements : LS7044 Legionella BCYE Supplement, LS7045 BCYE without Cysteine
  • Letheen agar modified is intended for use in the isolation of microorganisms from cosmetics. The casein peptone, meat peptone, beef extract and yeast extract act as carbon, nitrogen and vitamin sources in this medium. Glucose is a fermentable carbohydrate. Sodium chloride maintains the osmotic balance of the medium. The sodium bisulfite, lecithin and polysorbate 80 inactivates quaternary ammonium compounds. Polysorbate 80 neutralises phenols, formalin, hexachlorophene, and in combination with the lecithin, ethanol.
  • KM0206

    Letheen Broth

    Letheen broth when prepared with polysorbate 80 is used for the testing of quaternary ammonium compounds for antimicrobial activity. Letheen broth is recommended by the Official Methods of Analysis of the Association of Official Analytical Chemists (AOAC). (1) The enzymatic digest of animal tissue and beef extract act as carbon, nitrogen and vitamin sources in this medium. Sodium chloride maintains the osmotic balance of the medium. Lecithin inactivates quaternary ammonium compounds. Polysorbate 80 must be added to the medium prior to sterilisation. Polysorbate 80 neutralises phenols, formalin, hexachlorophene, and in combination with the lecithin, ethanol. REFERENCE (1) Association of Official Analytical Chemists. 1995. Official methods of analysis, 16th ed. Association of Official Analytical Chemists, Washington, D.C
  • Letheen broth modified is intended for use in the isolation of microorganisms from cosmetics. The enzymatic digest of animal tissue, enzymatic digest of casein, yeast extract and beef extract act as carbon, nitrogen and vitamin sources in this medium. Sodium chloride maintains the osmotic balance of the medium. The sodium bisulfite and lecithin inactivates quaternary ammonium compounds. Polysorbate 80 must be added to the medium prior to sterilisation. Polysorbate 80 neutralises phenols, formalin, hexachlorophene, and in combination with the lecithin, ethanol.
  • Listeria isolation medium (Oxford) is based on the formulation described by Curtis et al. and is used for the isolation and identification of Listeria spp. in food and clinical laboratories. Columbia agar base provides the required carbon, nitrogen and vitamins in the medium. Lithium chloride is included to inhibit enterococci. Aesculin is present as an indicator; Listeria spp. will hydrolyse aesculin and the associated reaction with the ferric ammonium citrate gives rise to a black precipitate around the colonies. Selectivity is enhanced by addition of Listeria Oxford selective supplement (LS0030). This contains acriflavine, cefoxitin, colistin, fosfomycin and amphotericin to inhibit any yeasts present and some other Gram-positive and Gram-negative organisms that may be present in specimens. Related Supplements : LS0030 Listeria Oxford Selective Supplement
  • Long and Hammer agar is for the detection of aerobic microorganisms in fish and fish products. This media is recommended for the determination of spoilage organisms in fresh and lightly preserved seafoods. (1) The proteose peptone acts as a nitrogen, carbon and vitamin source. Gelatine is a protein source and solidifying agent. Sodium chloride maintains the osmotic balance and di-potassium hydrogen phosphate is a buffer. 1) Nordic Committee on Food Analysis. (2006) Aerobic count and specific spoilage organisms in fish and fish products. NMKL Method No 184
  • Lowenstein-Jensen medium is based on the original formulation of Lowenstein that was subsequently modified by Jensen. It is used with fresh egg and glycerol for the isolation and presumptive identification of Mycobacterium spp., particularly Mycobacterium tuberculosis, from clinical samples. L-Asparagine and Potato starch are sources of nitrogen and vitamins in the medium. Potassium hydrogen phosphate and magnesium sulphate enhance organism growth and act as buffers. Sodium citrate and malachite green are selective agents that have inhibitory effects on organisms other than the mycobacteria. Malachite green is also incorporated into the medium to provide a colour contrast between the colonies and the medium. The required addition of egg emulsion provides the fatty acids and protein required for the metabolism of mycobacteria. Glycerol is also added which is said to enhance the growth of Mycobacterium tuberculosis however other strains of mycobacteria, particularly Mycobacterium bovis, may be inhibited by its presence. Subsequently, sodium pyruvate (12.5 g/600ml) may be used as an alternative to glycerol to encourage the growth of Mycobacterium bovis.  
  • Lysine iron agar is a differential medium for the detection of Salmonella spp. and other enteric pathogens on the basis of lysine decarboxylase and hydrogen sulphide production. Lysine iron agar was originally developed by Edwards and Fife(1) for Salmonella arizonae detection. The peptone and yeast extract provides the required nitrogen, carbon and vitamins. Glucose is a fermentable carbohydrate. L-lysine is used to detect lysine decarboxylase and lysine deaminase enzymes. Sodium thiosulphate is reduced to hydrogen sulphide which is detected by the ferric citrate indicator. Sodium chloride maintains the osmotic balance. Bromocresol purple is a pH indicator. For use the medium is inoculated using a pure culture of the test organism which should be smeared onto the surface of the slope and stabbed into the butt of the medium. For details of the many reactions that may arise during the use of this medium reference should be made to one of the many standard textbooks.
  • MacConkey agar No. 3 is a selective medium primarily for the isolation of Enterobacteriacae from waters and sewage. This media differs from the original MacConkey formulation in that as well as bile salts, crystal violet has been included as an additional selective agent. This has the effect of inhibiting Gram-positive organisms. The peptone acts as a nitrogen, carbon and vitamin source. Sodium chloride maintains osmotic balance. Lactose is a carbohydrate and during its fermentation causes a confined pH drop around the bacterial colony. This causes a colour change in the pH indicator, neutral red and bile precipitation.  
  • This is a selective medium for the isolation and differentiation of bile tolerant Gram-negative (enteric) and Gram-positive (staphylococci and enterococci) organisms and has uses in all areas of bacteriology. This medium is recommended by the World Health Organisation and the Department of Health for the bacteriological examination of water. It has the disadvantage that many strains of Proteus spp. will spread on it and for this reason MacConkey Agar without salt and crystal violet may be preferred (KM0011).  
  • This medium was first introduced by MacConkey in 1905 for the isolation and differentiation of lactose and non-lactose fermenting enteric bacteria containing swarming strains of Proteus spp. MacConkey agar without salt and crystal violet is a differential medium that restricts swarming of Proteus spp. as sodium chloride is omitted from the medium to provide an electrolyte deficient medium. The omission of crystal violet permits the growth of Staphylococcus spp. and Enterococcus spp. The peptone is the nitrogen, carbon and vitamin source in this medium. Lactose is the fermentable carbohydrate. Lactose fermentation causes a local pH drop around the colonies which will react with the pH indicator, neutral red, and hence aids in differentiation. Bile salts act as the selective agent. Related Supplements : LS0189 Cefotaxime Supplement (1mg/L)
  • A selective medium for the enrichment of Enterobacteriaceae and the detection of Escherichia coli in pharmaceutical products. The inclusion of bromocresol purple indicator makes the colour change caused by acid production from the fermentation of lactose easy to read with gas formation. The presence of ox bile helps to suppress the growth of Gram-positive and non-enteric bacterial species. This formulation complies with the Harmonized USP/EP/JP. Nitrogen is supplied by the gelatin peptone whilst lactose serves as the fermentable carbohydrate source. Oxbile is the selective agent helping to suppress Gram-positive organisms and bromocresol purple detects the pH change as a result of the fermentation of lactose.
  • KM8005

    Malt Extract

    Malt extract is sourced from hydrolyzed vegetal protein. Due to the high concentration of carbohydrate malt extract is particularly suited for the cultivation of yeasts and moulds especially in contaminated dairy products. In microbiological culture media it provides a source of nutrients, protein, and carbon.  
  • Malt extract agar is used for the detection, isolation and enumeration yeasts and moulds. 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. Malt extract agar can also be used for the cultivation of fungi, although with the prolonged incubation necessary, cultures may become overgrown by bacteria. The selectivity of the medium can be increased by lowering the pH to 3.5-4.0 or by the addition of selective agents such as chloramphenicol. Related Supplements : LS0050 Chloramphenicol Selective Supplement
  • 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.  
  • Mannitol Salt Agar is selective medium for the isolation of pathogenic staphylococci. The medium conforms to the requirements of the Harmonised USP/EP/JP. Chapman showed that adding a high level of sodium chloride to Phenol Red Mannitol Agar allowed for the recovery of pathogenic staphylococci. Pathogenic staphylococci produced yellow colonies whereas non-pathogenic staphylococci produced small red colonies. Pancreatic digest of casein, peptic digest of animal tissue and beef extract provide the required nitrogen, carbon and vitamins. The high level of sodium chloride inhibits most organisms other than staphylococci. Mannitol is a carbohydrate that is fermented by coagulase positive staphylococci. Phenol red is the pH indicator.
  • KM0062

    Marine Agar

    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
  • 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.  
  • KM8004

    Meat Peptone

    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.  
  • 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
  • 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
  • Mueller Hinton agar is used for antimicrobial susceptibility testing by the disk diffusion method as described by Bauer-Kirby. It has been approved as the definitive medium for this purpose by the European Committee on Anitmicrobial Susceptibility Testing (EUCAST). This formulation conforms to Clinical and Laboratory Standard Institute (CLSI). Beef extract and acid hydrolysate of casein provides the required nitrogen, carbon and vitamins in the medium. Starch absorbs any toxic metabolites produced. The medium contains low levels of thymidine and thymine and controlled levels of calcium and magnesium ions. The base medium can be supplemented with blood (5 – 10%). Nicotinamide adenine dinucleotide (NAD) may be added at 20 mg/L to make the medium suitable for use with more fastidious organisms such as Streptococcus pneumoniae and Haemophilus influenzae (LS0005). Related Supplements : LS0005 NAD Supplement (20mgs/L), Defibrinated Horse Blood
  • Approved by the Clinical & Laboratory Standards Institute (CLSI formerly known as the NCCLS) in USA this medium can be considered as an alternative to Iso-Sensitest Broth for antimicrobial sensitivity testing and MIC determinations by tube dilution methods. (1&2) Beef extract and acid hydrolysate of casein provides the required nitrogen, carbon and vitamins in the medium. Starch absorbs any toxic metabolites produced. References (1) Clinical and Laboratory Standards Institute. 2006. Performance standards for antimicrobial disk susceptibility tests. Approved standard M2-A9. CLSI, Wayne, PA. (2) MacFaddin, J. 1985. Media for isolation cultivation, identification maintenance of medical bacteria. Williams & Williams, Baltimore.
  • This is a selective enrichment broth for the isolation of Salmonella spp. primarily from food and food product samples and conforms to the requirements ISO 6579:2002. It can however be used in other areas including clinical and environmental specimens. Salmonella spp. reduce tetrathionate and will proliferate in the medium whilst most other enteric organisms are inhibited. Unlike the older traditional tetrathionate broth the addition of novobiocin (40 mg/l) improves the inhibition of Proteus spp. Immediately prior to use it is necessary to add 20 ml/l of 2% iodine/iodide solution (BM0946). Once the iodine/iodide solution has been added the medium should be used immediately and cannot be stored for future use. NB: As this is an opaque medium, the turbidity of the broth alone cannot be used as an indication of growth. Related Supplements : LS0024 Novobiocin Supplement (20mgs/L)
  • Mycological agar is a selective medium for the isolation of pathogenic fungi, particularly dermatophytes, from clinical specimens. Enzymatic digest of soybean meal provides the required carbon, nitrogen and vitamins. Glucose is an energy source for the metabolism of fungi. The addition of chloramphenicol further reduces the risk of bacterial contamination when processing material that may be heavily contaminated with coliforms. Cycloheximide should also be added (0.4g/L) to suppress the growth of commensal yeasts and saprophytic fungi.  
  • KM0141

    Nutrient Agar

    A basic general-purpose medium suitable for use in the cultivation of the less fastidious organisms particularly those that do not require the addition of blood or other enrichment. When used to prepare agar slopes or agar butts, the medium can be used to maintain control organisms. The peptone provides the required carbon, nitrogen and vitamins. Sodium chloride maintains osmotic balance.  
  • A general-purpose medium for the cultivation of organisms that are less fastidious in their nutritional requirements. The beef extract, peptone and yeast extract act as carbon, nitrogen and vitamin sources in this medium. Sodium chloride maintains osmotic balance.  
  • Nutrient Broth No.2 is used for the cultivation of fastidious pathogens and other microorganisms. This general use medium, rich in nutrients, allows the growth of bacteria when there is a low level of cells. The medium is particularly suitable as a secondary growth medium for staphylococci to be tested for coagulase production and also be used for sterility testing of aerobic organisms. Beef extract and peptone provide the required carbon, nitrogen and vitamins. Sodium chloride maintains osmotic balance.  
  • O-F Medium is used for the determination of oxidative and fermentative metabolism of carbohydrates by Gram-negative bacilli (1). This is on the basis of the acid reaction in either the open or closed system that has been covered with sterile paraffin oil. Changes in the covered agar are considered to be due to true fermentation, while changes in the open tubes are due to the oxidative utilization of the carbohydrate present. O-F Base Medium requires the addition of the specific carbohydrate being investigated. The enzymatic digest of casein provides the required nitrogen, carbon and vitamins in the media. Sodium chloride maintains the osmotic balance. Di-potassium hydrogen phosphate acts as a buffer and bromothymol blue is a pH indicator. The agar is a solidifying agent. Reference (1) Hugh, R. and Leifson, E.J. 1953. Bacteriol. 66:24-26.
  • Palcam agar is a selective differential medium for the isolation of Listeria monocytogenes from food, clinical and environmental specimens. The Columbia peptone mix and starch provide the required carbon, nitrogen and vitamins. Glucose is a fermentable carbohydrate. Differentiation of Listeria spp. from enterococci and staphylococci occurs through aesculin hydrolysis and mannitol fermentation. Listeria monocytogenes will hydrolyse aesculin and the associated reaction with the ferric ammonium citrate gives rise to a brown/black precipitate around the colonies. Listeria spp. do not however ferment mannitol. Mannitol fermentation is seen through a colour change of the colony or the area around the colony from red to yellow due to the production of acidic end products. Phenol red is the pH indicator in the medium. Lithium chloride is included to inhibit enterococci. The associated Palcam selective supplement, LS0038, contains polymyxin B, acriflavine and ceftazidime to inhibit other Gram-positive and Gram-negative organisms that may be present in specimens. Related Supplements : LS0038 PALCAM Selective Supplement
  • Pasteurella Agar Base is an non-selective medium capable of supporting the growth of Pasteurella spp. Pasteurella spp.are spherical, ovoid or rod-shaped cells 0.3-1.0μm in diameter and 1.0-2.0μm in length. Cells are Gram negative, and occur singly, or in pairs or short chains. Bipolar staining may be seen and capsules may be present. All species are non-motile, and are facultatively anaerobic.(1) With further enrichment using 5-10% blood and selective antimicrobials, most Pasteurella spp. can be isolated. There is no haemolysis on blood agar for Pasteurella spp. and the organism will not regularly exhibit satellitism around colonies of Staphylococcus spp. The peptones act as carbon, nitrogen and vitamin sources in this medium. Sodium chloride maintains the osmotic balance and the agar is a solidifying agent. The medium is made selective through the addition of LS0057, Pasteurella agar selective supplement. REFERENCE (1) Standards Unit, Microbiology Services, PHE. 1995. UK Standards for Microbiology Investigations. Identification of Pasteurella species and Morphologically Similar Organisms. 3, 1-28.
  • KM0149

    Peptone Water

    Peptone water is a general-purpose medium that supports thecultivation of non-fastidious organisms. This non-selective medium can be used a basal medium for biochemical tests such as carbohydrate fermentation and production of indole. Tryptone and peptone act as sources of carbon, nitrogen and vitamins in this medium and sodium chloride maintains osmotic balance.  
  • Perfringens Agar Base is a base medium that allows the enumeration of Clostridium perfringens from food samples. As a base medium, Perfringens Agar Base can have several supplementary and selective agents added to increase selectivity. The addition of Eye Yolk Emulsion (BM0140) allows the detection of lecithinase activity as precipitates are formed by C. perfringens. The addition of D-cycloserine (LS0023) can be used to inhibit other facultative anaerobes, as used in Tryptose-Sulphite-Cycloserine (TSC) agar. (1&2) Alternately, kanamycin and polymyxin B (LS0025) can be used to inhibit other coliforms generally found in food samples, as used in Shahidi-Ferguson Perfringens (SFP) agar.(3) The tryptose and soy peptone provide the required nitrogen, carbon and minerals. Yeast extract provide the essential vitamins, including the vitamin B group, needed for growth. The ferric ammonium citrate and sodium metabisulphite allows the reduction of sulphites to hydrogen sulphide by C. perfringens, which produces black colonies. References (1) ISO- 7937:2004. Microbiology of food and animal feeding stuffs- Horizontal method for the enumeration of Clostridium perfringens - Colony count technique (2) Harmon, S.M., Kauttar, D.A. and Peeler, J.T. 1971. Improved Medium for Enumeration of Clostridium perfringens. Appl. Microbiol. 22:688-692. (3) Shahidi S. A. and Ferguson A. R. 1971 New Quantitative, Qualitative, and Confirmatory Media for Rapid Analysis of Food for Clostridium perfringens. Appl. Microbiol. 21:500-506
  • Phosphate-buffered saline (PBS) is a buffer solution used in biological research. It is a water-based salt solution containing sodium phosphate, sodium chloride and, in some formulations, it contains potassium chloride and potassium phosphate. The osmolality and ion concentrations of the solutions match those of the human body (isotonic) and are non-toxic to most cells. This balanced salt solution is issued to meet the requirements of those tissue culture workers who use the Dulbecco Solution with and without calcium and magnesium.
  • Plate Count Agar is formulated to the A.P.H.A. specification developed by Buchbinder et al. This medium is intended for use in food, dairy and water bacteriology to perform Total Viable Counts. Tryptone and yeast extract provide the required carbon, nitrogen and vitamins. Glucose is a fermentable carbohydrate.  
  • Potato dextrose agar is recommended for the detection and enumeration of yeasts and moulds in food and dairy products.It can also be used for the cultivation of fungi although with the prolonged incubation necessary cultures may become overgrown by bacteria. The low pH (5.6) suppresses the growth of most bacteria and the low mineral content ensures good pigment production by fungi where appropriate. This medium meets the requirements of the Harmonised USP/EP/JP.(1,2&3) REFERENCES (1) United States Pharmacopeial Convention. 2007. The United States pharmacopeia, 31st ed., Amended Chapters 61, 62, 111. The United States Pharmacopeial Convention, Rockville, MD. (2) Directorate for the Quality of Medicines of the Council of Europe (EDQM). 2007. The European Pharmacopoeia, Amended Chapters 2.6.12, 2.6.13, 5.1.4, Council of Europe, 67075 Strasbourg Cedex, France. (3) Japanese Pharmacopoeia. 2007. Society of Japanese Pharmacopoeia. Amended Chapters 35.1, 35.2, 7. The Minister of Health, Labor, and Welfare.
  • Primary Membrane Lactose Glucuronide Agar (mLGA) is used for the differentiation and enumeration of Escherichia coli and other coliforms through a single membrane filtration technique. The peptone and yeast extract provide the required nitrogen, carbon and vitamins. Sodium pyruvate protects injured cells enhancing recovery and growth of coliforms. Sodium lauryl sulphate is a selective agent that inhibits Gram-positive organisms. Lactose is a fermentable carbohydrate and phenol red is a pH indicator. Lactose fermentation will result in yellow colonies. X-glucuronide is a chromogenic substrate which can be cleaved by the enzyme ß-glucuronidase present in E. coli. This results in a blue colony, but in combination with lactose fermentations colonies will appear green. NB: Prepared plates stored at 2–8°C may show formation of surface crystals which will disappear when plates are warmed to >20°C Related Supplements :
  • Recent developments in culture media have given rise to the use of chromogenic substrates as a means of differentiating bacteria particularly among the coliform group of organisms. This is one such medium and has been developed with the aim of simplifying the differentiation and presumptive identification of the main organisms usually found in Urinary Tract Infections (UTI). The peptone is the source of the required nitrogen, carbon and vitamins. Based on the traditional CLED medium, to prevent the swarming of Proteus spp., two chromogens are present in the medium. One allows the detection of enterococci giving rise to blue colonies whilst the second results in purple colonies of E. coli. Phenylalanine and tryptophan are also included as indicators of tryptophan deaminase activity producing brown colonies of Proteus spp. Related Supplements : SHS500 Sterile Horse Serum 500ml
  • This is a selective medium for the isolation of Pseudomonas spp. primarily in food, water and environmental samples. Pseudomonas agar base is on Kings A medium which uses magnesium and potassium salts to enhance pigment production. The gelatine peptone and acid hydrolysed casein acts as a nitrogen, vitamins, and carbon source. Magnesium chloride and potassium sulphate promotes production of pyocyanin. The medium can be made selective for P. aeruginosa by the addition of Pseudomonas CN Supplement (LS0006). Alternatively, the medium can be made selective for Pseudomonas spp. generally by the addition of Pseudomonas CFC Selective Supplement (LS0026). The presence of blue/green or brown pigmentation or fluorescence is indicative of presumptive Pseudomonas spp. It should be noted however that further testing must be carried out to confirm the full identity of the organism.
  • KM0082

    R2A Agar

    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.  
  • 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
  • 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.  
  • Sabouraud Dextrose Agar is one of several media available for theisolation 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. The tryptone and meat peptone provide the nitrogen and vitamins required for organism growth in Sabouraud Dextrose Agar. 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. Higher levels of selectivity can be achieved against bacterial species by the addition of chloramphenicol. NB: This is a basic medium only and contains no additional supplements. Related Supplements : LS0050 Chloramphenicol Selective Supplement
  • 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.
  • 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.
  • 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.
  • Selenite cystine broth is a modification of selenite F broth and is for the selective enrichment of Salmonellae spp. from clinical, food and environmental specimens. The peptone acts as a nitrogen, carbon and vitamin source. Lactose is a fermentable carbohydrate and sodium phosphate is a buffer. L-cystine is used to enhance the recovery of Salmonellae spp. in low numbers. The medium is made selective by the addition of sodium biselenite (KM8021). Following overnight incubation subculture(s) are usually made on to one or more of the many selective enteric solid media.