Dehydrated 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
  • 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.

  • 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.