Ready-to-use media
Glucose OF Medium ISO
Fluid medium used for determining the oxidative and/or fermentative metabolism of Gram-negative bacilli (Enterobacteriaceae) according to ISO.
- Cat. No.
- LC-4026
- Category
- Ready-to-use media
- Format
- 20 tubes
- ISO 17025 quality control
- Yes
- Storage
- 8 to 25 °C
- Minimum guaranteed shelf life
- 4 months
- Standards
- ISO 21528
- Also available
- Dehydrated medium, 1 format (LC-2150)
Using this medium, Hugh and Leifson were able to differentiate Gram-negative bacteria into three categories: fermentative, oxidative and inactive.
Key features
Applications
Confirmation of enterobacteria.
Industry
Food.
Standards
ISO 21528.
Presentation
20 tubes, 16 x 113 mm, with 10 ± 0.2 mL.
Description and technique
Description
The current formulation has been adapted to the ISO standard described in the Bibliography.
Technique
Proceed according to the current ISO standard.
The inoculation technique is stab inoculation. One tube is covered with a vaseline layer in order to induce an anaerobic environment that forces the strain to carry out fermentation.
Fermentative organisms produce a large amount of acid in both the tubes, and this is indicated by the yellow colouration of the Bromothymol Blue indicator. Bacteria that utilise an oxidative metabolic pathway carry out this reaction only in the tube without the vaseline. Inactive strains do not use sugars and therefore do not induce any change in either tube.
In some instances a slight blue colouration, probably due to alkalinization by peptone degradation, can occur.
Note: pH decrease may appear over time without affecting its performance.
Presentation
| Presentation | 20 tubes, 16 x 113 mm |
|---|---|
| Filling | 10 ± 0.2 mL |
| Packaging | 1 box with 20 tubes, 16 x 113 mm glass tubes, ink labelled and metallic cap. |
Composition
| Ingredient | g/L |
|---|---|
| Casein peptone | 2.00 |
| Sodium chloride | 5.00 |
| D(+) Glucose | 10.0 |
| Dipotassium phosphate | 0.30 |
| Bromothymol blue | 0.08 |
| Agar | 3.00 |
Quality control
Physical/chemical control
| Color | Green |
|---|---|
| pH | 6.8 ± 0.2 at 25 °C |
Microbiological control
Inoculate by stabbing with and without vaseline.
Microbiological control according to ISO 11133:2014/Amd 1:2018.
Aerobiosis. Incubation at 35 ± 2 °C. Reading at 24 hours.
| Microorganism | Growth |
|---|---|
| Ps. aeruginosaATCC 27853, WDCM 00025 | Good growth - O/F: Pos./Neg. |
| Escherichia coliATCC 25922, WDCM 00013 | Good growth - O/F: Pos./Pos. Yellow medium |
| Salmonella typhimuriumATCC 14028, WDCM 00031 | Good growth - O/F: Pos./Pos. Yellow medium |
| Salmonella entericaATCC 13076, WDCM 00030 | Good growth - O/F: Pos./Pos. Yellow medium |
Sterility control
Incubation 48 hours at 30-35 °C and 48 hours at 20-25 °C: NO GROWTH.
Check at 7 days after incubation in same conditions.
Bibliography
- ATLAS, R.M., L.C. PARKS (1993) Handbook of Microbiological Media. CRC Press, Inc. London.
- COWAN, S.T. (1974) Cowan and Steel's manual for the identification of medical bacteria. 2nd ed. Cambridge University Press. UK.
- DOWNES, F.P. & K. ITO (2001) Compendium of Methods for the Microbiological Examination of Foods. 4th ed. APHA. Washington. DC. USA.
- FORBES, B.A., D.F. SAHM & A.S. WEISSFELD (Eds.) (1998) Bailey & Scott's Diagnostic Microbiology. 10th ed. Mosby. St Louis. MO. USA.
- HORWITZ, W. (2000) Official Methods of Analysis of the AOAC International. 17th ed. Gaithersburg. MD. USA.
- HUGH, R. & E. LEIFSON (1953) The taxonomic significance of fermentative vs. Oxidative metabolism of carbohydrates by various Gram negative bacteria. J. Bact. 66:24.
- ISENBERG, H.D. (1992) Clinical Microbiology Procedures Handbook. ASM Press. Washington. DC. USA.
- ISENBERG, H.D. (1998) Essential Procedures for Clinical Microbiology. ASM Press. Washington. DC. USA.
- ISO 21528-1:2017 Standard. Microbiology of food chain - Horizontal methods for the detection and enumeration of Enterobacteriaceae - Part 1: Detection of Enterobacteriaceae.
- ISO 21528-2 (2017) Microbiology of the food chain - Horizontal methods for the detection and enumeration of Enterobacteriaceae - Part 2: Colony-count method.
- MURRAY, P.R., E.J. BARON, J.H. JORGENSEN, M.A. PFALLER & R.H. YOLKEN (Eds.) (2003) Manual of Clinical Microbiology. 8th ed. ASM Press. Washington. DC. USA.
- MacFADDIN, J.F. (1985) Media for Isolation-cultivation-identification-maintenance of Medical Bacteria. Vol. I. Williams & Wilkins. Baltimore. MD. USA.
- US FDA (Food and Drug Administration) (1998) Bacteriological Analytical Manual. 8th ed. AOAC International. Gaithersburg. MD. USA.
- WINN, W., S. ALLEN, W. JANDA, E. KONEMAN, G. PROCOP, G. WOODS & P. SCHRECKENBERER (2006) Koneman's Color Atlas and Textbook of Diagnostic Microbiology. 6th ed. Lippincott, Williams & Wilkins. Philadelphia. PA. USA.
What you receive
The product
Shipped under controlled temperature when the product requires it.
Lot certificate
Every lot comes with its certificate.
Tracked shipment
Follow your shipment live, from our warehouse to your lab.
Related products
Frequently asked questions
Can I ask for formats other than those listed?
Yes: custom formats and OEM packs are available on request. Tell us the quantities you need.
How do I see the prices?
Prices are shown after you sign in to the customer area, with your account discount already applied.
How long does delivery take?
We give you the availability with the quote, within 24 hours of your request.