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Originally introduced for the isolation and differentiation of Lactose & Non-Lactose Fermenting enteric organisms the medium in this case has been modified to improve the isolation of staphylococci and enterococci. The absence of Sodium Chloride provides a low electrolyte medium that prevents spreading of most Proteus spp. Although recommended for use in the examination of urine samples in clinical laboratories it has uses in Food, Water and Dairy applications. -
This is a medium for the cultivation of yeasts and moulds. The high carbohydrate content is said to ensure rapid growth while the low pH (5.4) inhibits most bacteria. Malt Extract Agar can also be used for the cultivation of fungi although with the prolonged incubation necessary cultures may become overgrown by bacteria. -
Middlebrooks 7H11 Selective Medium is an agar based medium for the isolation of Mycobacteria spp from clinical specimens. It differs from Middlebrooks 7H10 Agar in that it has a higher concentration of Malachite Green. The medium is complex and includes L-Glutamic Acid, Ammonium Sulphate, Sodium Citrate, Pyridoxine and Biotin as growth factors and Magnesium Sulphate, Ferric Ammonium Citrate as sources of trace ions. The medium is also made selective by the inclusion of Ticarcillin, Polymixin B, Trimethoprim and Amphotericin B. As with egg media Glycerol is included to enhance the growth of the Mycobacteria and Malachite Green is incorporated to provide a colour contrast between the colonies and the medium as well as contributing some inhibitory effect on organisms other than mycobacteria. -
This medium is used for the presumptive identification of Pseudomonas aeruginosa from water and environmental samples. Pseudomonas aeruginosa is presumptively identified by the characteristic green pigmentation of the colonies with hydrolysis of casein (clear zones around each colony). -
Approved by the Clinical Laboratory Standards Institute (CLSI) in USA this medium can be considered as an alternative to Iso-Sensitest Agar for antimicrobial sensitivity testing by disc diffusion methods. It is low in Thymine and Thymidine and is therefore suitable for use in testing Sulphonamides & Trimethoprim without the addition of Lysed Blood. -
Approved by the National Committee for Clinical Laboratory Standards (NCCLS) in USA this medium is approved for use in antimicrobial sensitivity testing by the disc diffusion method and is recommended particularly for use with the Bauer-Kirby Technique It is low in Thymine and Thymidine and is therefore suitable for use in testing Sulphonamides & Trimethoprim and controlled to ensure correct zone sizes with Tetracyline and Aminoglycoside antibiotics. It can be considered as an alternative to Iso-Sensitest Agar. This particular formulation has an additional 2% Sodium Chloride added to the medium making it suitable for the detection of resistance to Methicillin in staphylococci and it is included in the recommendations of British Society for Antimicrobial Chemotherapy (BSAC) for this purpose. It is not however recommended for testing of organisms requiring a CO2 enriched environment due to the pH effect on the medium. If incubation in a CO2 enriched environment is essential control organisms should be included to confirm that results have not been altered. -
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. -
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. -
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. -
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 (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. -
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. -
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. -
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.
