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Mueller-Hinton with 2% Glucose & Methylene Blue (25ml) This medium is intended for use as a means of differentiation of Candida spp. based on Mueller-Hinton Agar base. The medium is modified by the addition of Glucose and Methylene Blue indicator and is the recommended media for the susceptibility testing of Yeasts according to the CLSI M44-A2 document. -
A selective medium for the isolation of fungi, particularly dermatophytes from clinical specimens, Mycological Agar is suitable for use in all areas of Mycology. The medium inhibits most bacteria due to the addition of Chloramphenicol which is added to reduce the risk of bacterial contamination when processing material that may be heavily contaminated particularly with Coliforms. Cycloheximide is also added to suppress the growth of yeasts and saprophytic fungi. -
Based on Fastidious Anaerobe Agar Base with added Egg Yolk Emulsion, this medium can be used to test Clostridium perfringens for phospholipase production. A zone of opalescence around the colonies is indicative of a positive reaction. It can also be used as an aid to identification of Clostridium perfringens if antitoxin is spread onto half of the plate prior to inoculation (Nagler Reaction). -
Pages Amoeba Saline & Agar No.1 This is a non-nutrient medium based on Page’s Amoeba Saline, a buffered salt solution, solidified with 1.5% Agar. -
This is a selective differential medium for the isolation of Listeria monocytogenes from food, clinical and environmental specimens. -
This medium is recommended for the detection and enumeration of yeasts and fungi in a variety of sample types. The low pH (5.6) and addition of streptomycin will ensure that the growth of most bacterial species is inhibited and the low mineral content ensures good pigment production by fungi where appropriate. -
Chromogenic Coliform Agar (CCA) Chromogenic Coliform Agar (CCA) conforms to the ISO 9308-1 guidelines for the detection, enumeration and isolation of coliforms and more specifically Escherichia coli in water samples by the membrane-filtration technique. The colonial differentiation is provided by the chromogenic substrates, Salmon-GAL and X-glucuronide. Salmon-GAL is used for the detection of β-D-galactosidase enzymatic activity. X-glucuronide is used for the detection of β-D-Glucoronidase enzymatic activity. β-D-galactosidase, expressed by all coliforms, cleaves the Salmon-GAL substrate and producing red/pink coloured colonies. Unlike other coliforms, Escherichia coli leaves both Salmon-GAL and X-glucuronide producing a violet/blue coloured colonies. Tryptophan is used to increase detection reliability by improving the indole reaction. The peptones, sodium pyruvate and sorbitol support bacterial growth and simple recovery of sub-lethal thermally injured coliforms. Sodium di-hydrogen phosphate and di-sodium hydrogen phosphate phosphate buffer the medium and sodium chloride is used to achieve osmotic balance. The selectivity is attained by the addition of Tergitol® 7 as it inhibits the growth of Gram positive bacteria. -
Traditionally, membrane Lauryl Suphate Broth (mLSB) was used as the standard media for isolating coliforms (including E. coli) from drinking water. Primary membrane Lactose Glucuronide Agar (mLGA) is a chromogenic modification of mLSB formulation aimed at reducing costs by reducing the number of filters used per test sample and aiding in the recovery and identification of coliforms and <em,>E. coli . The medium has been modified from the mLSB formulation by the incorporation of X-glucuronide, sodium pyruvate and agar. X-glucuronide is incorporated to allow for the presumptive isolation of E. coli, sodium pyruvate aids recovery of chlorine stressed organisms and agar is incorporated to remove the need for absorbent pads. This medium is recommended for the enumeration of coliform bacteria and E. coli by a single membrane filtration technique in The Environment Agency’s - The Microbiology of Drinking Water 2009 (Part 4). -
Tryptone Bile X (TBX) - Glucuronide Agar 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 as a selective medium for the isolation and enumeration of Escherichia coli in food samples. Based on Tryptone Bile Agar it incorporates the chromogenic agent X-glucuronide, which detects glucuronidase activity, the same enzyme as is detected by MUG reagent. Escherichia coli can be differentiated from other coliform organisms by the presence of glucuronidase resulting in the colonies being blue/green while the other coliforms are colourless. For information on the full technical detail as to the functionality of this medium reference should be made to the many publications available. -
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. 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. This media is an opaque version to aid differentiation and presumptive identification of the bacteria isolated. -
This is a medium for the isolation and identification of Group B streptococci. The principal of the medium is based on the ability of group B streptococci to produce unique orange/red pigmented colonies when incubated anaerobically, particularly on media containing starch products. This medium is non-selective so other organisms will grow on this medium but they do not produce the characteristic pigment. -
Pseudomonas Agar Base with 1% Glycerol, Cephalothin, Fucidin & Cetrimide (CFC) This is a selective medium for the isolation of Pseudomonas spp primarily in food, water and environmental samples. The medium uses Magnesium and Potassium salts to enhance pigment production and is made selective by the addition of CFC supplement. 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. -
Pseudomonas Agar Base with 1% Glycerol & CN Supplement A selective medium for the isolation of Pseudomonas aeruginosa the medium is made selective by the inclusion of Cetrimide and Naladixic Acid (CN) supplement to significantly reduce the enteric organisms particularly Proteus and Klebsiella spp. Magnesium and Potassium salts are included to enhance the production of the pigments pyocyanin and fluorescein. -
A selective medium for the isolation of Pseudomonas spp. primarily in food, water and environmental samples the medium is made selective by the addition of CFC supplement (cetrimide, at a concentration of 10mg/L which is said to allow the growth of all pseudomonads, cephalothin and fucidin). 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. -
R2A medium was developed to determine the bacterial count including heterotrophic bacteria in potable waters during treatment and distribution. This medium has a low nutritional content and therefore requires extended incubation times. It is recommended by the Environmental Agency, Methods for the Examination of Waters and Associated Materials, and Standard Methods for the Enumeration of Water and Wastewater. -
RPMI Medium for E-Test RPMI Medium is recommended for use in anti-fungal susceptibility testing of yeasts from clinical isolates using the E-Test method. The medium is based on a simple Glucose Agar with added RPMI-1640 Medium (without Sodium Bicarbonate & Phenol Red), which supplies the necessary vitamins and amino-acids, and MOPS (3-(Morpholino)propanesulfonic Acid) Buffer to maintain the medium pH during incubation. -
Sabouraud Dextrose Agar with Chloramphenicol (0.5g/L) 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. Due to the higher pH of the medium, an increased concentration of chloramphenicol is included to improve the selectivity of the media and inhibit a range of Gram-positive and Gram negative bacteria. 1. Sabouraud, R. 1892. Ann. Dermatol. Syphilol. 3:1061. -
Sabouraud Dextrose Agar with Chloramphenicol (50mg/L) & Cyclohexamide (Actidione) (300mg/L) A selective medium for the isolation of fungi, Sabouraud Dextrose Agar is suitable for use in all areas of Mycology. The low pH of the medium inhibits most bacteria however in this formulation Chloramphenicol (50mg/L) is added to further reduce the risk when processing material that may be heavily contaminated particularly with coliforms. Cycloheximide is also added to suppress the growth of yeasts and saprophytic fungi. -
This is a modification of Sabouraud Dextrose Agar. The low pH (5.6) of the medium is inhibitory to most bacteria and it has been made specifically selective by the addition of colistin and gentamicin. This further reduces the risk of bacterial contamination when processing material that may be heavily contaminated particularly with Gram negative organisms such as Pseudomonas aeruginosa. -
Originally intended as a medium for the enumeration of enterococci in water using Membrane Filtration, this medium has become more popular in many other areas such as food bacteriology. The medium contains Tetrazolium Chloride, which is reduced by enterococci to the insoluble red dye Formazan resulting in dark red colonies of enterococci on the agar. It should be noted that this reaction is not exclusive to enterococci and colonies should be confirmed by additional testing e.g. Aesculin hydrolysis. -
This is a differential medium for the isolation of Escherichia coli 0157:H7. It differs from other MacConkey media in that lactose has been replaced by sorbitol. As Escherichia coli 0157:H7 does not ferment sorbitol, it produces pale translucent colonies whereas most other strains of Escherichia coli do ferment sorbitol and produce pink colonies. -
Sorbitol MacConkey with Cefixime & Tellurite (CT-Smac) This is a selective differential medium for the isolation of Escherichia coli 0157:H7. It differs from other MacConkey medium in that Lactose has been replaced by Sorbitol. As Escherichia coli 0157:H7 does not ferment Sorbitol it produces pale translucent colonies whereas most other strains of Escherichia coli are Sorbitol positive and produce pink colonies. The medium is made more selective by the addition of the antimicrobial Cefixime and Potassium Tellurite. -
Thiosulphate Citrate Bile Salts Sucrose (TCBS) Agar TCBS is a selective isolation medium for culture of pathogenic Vibrio spp. from clinical samples. The formulation was developed by Kobayashi, Enomoto, Skazaki and Kuwahara. This medium inhibits most enterobacteriacae for at least 24 hours. For the isolation of Vibrio spp. other than V.cholerae in environmental bacteriology, it is advisable to incubate at the lower temperature range of 20°C – 30°C. NB - It is not recommended to perform an oxidase test on any presumptive positive isolates directly from TCBS medium. -
This is a medium to detect Thermo-Stable-Nuclease from Staphylococcus aureus after heat inactivation of the organism. After boiling and centrifugation the supernatant is placed in a well in the plate and incubated for 4 hours. If present, the enzyme breaks down the DNA in the medium and produces a zone of clearing indicating a positive reaction. -
Triphenyltetrazolium Chloride Soya Tryptone (TSAT) Agar Complete Triphenyltetrazolium Chloride (TTC) has been added as an indicator to various media, and recommended by several workers as being helpful in the early recognition and identification of a variety of bacteria including Escherichia coli, Vibrio parahaemolyticus and enterococci. This particular formulation is based on a Tryptone Soya Agar with added Sucrose and is particularly useful when performing counts on food and food product samples. Many of the enterobacteriaceae and enterococci will reduce the TTC to a formazan which colours the colonies deep red making them easier to distinguish and identify. The presence of the Sucrose can also assist in the differentiation of Sucrose fermenting and non-fermenting strains. -
This is a plate count agar originally suggested by the American public Health Association for the estimation of total viable counts in food and dairy products. -
This is a medium for determining the mutagenicity of a chemical reagent using the Ames Test. A histidine requiring strain (His- ) of Salmonella typhimurium is inoculated into a mixture of salt agar, histidine solution and the test reagent, which is mixed and then used to overlay the media. Following incubation if the test reagent is mutagenic it will reverse the His- phenotype allowing growth to occur at a higher level than the control. -
Originally introduced as an aid to recovery of Shigella spp. XLD is also a first class medium for recovery of Salmonella spp. It differs from other media of this type in that it has less Sodium Desoxycholate as its selective agent. The indicator system is somewhat complex taking advantage of the fermentation or otherwise of three carbohydrates (Lactose Sucrose and Xylose) together with Lysine Decarboxylase and Sodium Thiosulphate as an indication of the presence or absence of Hydrogen Sulphide. -
Xylose Lysine Deoxycholate (XLD) Agar is used for the isolation and detection of Salmonella and Shigella spp. It differs from other media of this type in that it has less sodium deoxycholate as its selective agent. The indicator system is somewhat complex taking advantage of the fermentation or otherwise of three carbohydrates (lactose, sucrose and xylose) together with lysine decarboxylase and sodium thiosulphate as an indication of the presence or absence of hydrogen sulphide. The addition of novobiocin (20mg/L) improves the inhibition of Proteus spp. -
A nutrient agar corresponding to the standard formulation described in ISO 6222:1999. -
This is a selective medium for the isolation and enumeration of yeasts and moulds in dairy products. The medium has a low pH to inhibit bacterial growth and is made more selective by the inclusion of chloramphenicol. It complies with the requirements of ISO 6611 for the enumeration of yeasts and moulds . -
This is a selective medium for the isolation and enumeration of Yersinia spp. in clinical and food samples. It is made selective by the inclusion of Sodium desoxycholate, Crystal violet and the antimicrobials Cefsulodin, Novobiocin and Irgasan. Mannitol is also included which Yersinia ferments giving a colony that produces a ‘Bull’s Eye’ appearance. The majority of other enteric organisms are inhibited but if they do grow they produce a large pinkish colony with an opaque halo.
