Microbiology

Oxoid Czapek Dox Liquid Medium is used for cultivation of fungi.

Czapek Dox Liquid Medium, Oxoid Composition

Czapek Dox Liquid Medium, Oxoid Preparation:
Add 33.4g to 1 litre of distilled water. Mix well and distribute into final containers. Sterilise by autoclaving at 121°C for 15 minutes.

Storage conditions and Shelf life
Store dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared agar plates at 2-8°C.
Store tubes of broth at 15-25°C.

Enrich and isolate halophilic organisms, especially staphylococci, using Thermo Scientific™ Oxoid™ Salt Meat Broth Tablets. Salt Meat Broth Tablets are specially designed for the isolation of staphylococci from grossly contaminated specimens such as feces, particularly during the investigation of staphylococcal food poisoning. The medium is highly sensitive as it can detect even low numbers of staphylococci from samples having large proportions of heterogeneous microbial flora.^1,2

• Quantity: 100 tablets/bottle

Salt Meat Broth Tablets, Oxoid Composition

Salt Meat Broth, Oxoid Preparation:
Add 2 tablets to 10ml of distilled water in an appropriately sized test tube and soak for 5 minutes. Sterilise by autoclaving at 121°C for 15 minutes.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium at room temperature.

Oxoid Tryptone Water is used for detection of indole production.

Tryptone Water, Oxoid Composition

Tryptone Water, Oxoid Preparation:
Dissolve 15g in 1 litre of distilled water and distribute into final containers. Sterilise by autoclaving at 121°C for 15 minutes.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium at room temperature.

Presumptively detect, isolate and enumerate pathogenic staphylococci in milk, food, fish and other specimens with Thermo Scientific™ Oxoid™ Mannitol Salt Agar (Dehydrated). Due to high concentrations of salt in the medium, most unwanted bacteria are inhibited with the exception of some halophilic marine organisms. Presumptive coagulase-positive staphylococci produce colonies surrounded by bright yellow zones while non-pathogenic staphylococci produce colonies with reddish purple zones.

Mannitol Salt Agar, Oxoid Composition

Mannitol Salt Agar, Oxoid Preparation:
Suspend 111g in 1 litre of distilled water and bring to the boil to dissolve completely. Sterilise by autoclaving at 121°C for 15 minutes.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared plates at 2-8°C.

• Oxoid Hoyle Medium Base is used for isolation and differentiation of Corynebacterium diphtheriae Types.
• Requires addition of Potassium Tellurite 3.5%, Part No. SR0030J

Hoyle Medium Base, Oxoid Composition

Hoyle Medium, Oxoid Preparation:
Suspend 40g in 1 litre of distilled water and bring to the boil to dissolve completely. Sterilise by autoclaving at 121°C for 15 minutes. Cool to 55°C and add 50ml of Laked Horse Blood SR0048 and 10ml of 3.5% Potassium Tellurite solution SR0030, mix, and pour plates.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared plates at 2-8°C.

Precautions
It should be noted that not all corynebacteria produce the typical colonies described above – so in all cases it is advisable to use Hoyle medium in conjunction with the additional media and tests mentioned above.

Grow and maintain aerobic and anaerobic organisms with Thermo Scientific™ Oxoid™ Cooked Meat Medium (Dehydrated). The medium contains heart tissue, beef extracts, peptone and glucose for the cultivation of anaerobic and aerobic organisms. It has the ability to initiate bacterial growth from very small inocula and to maintain the viability of cultures over long periods of time1. Mixed cultures of bacteria survive in Cooked Meat Medium without displacing the slower growing organisms.

Cooked Meat Medium, Oxoid Composition

Cooked Meat Medium, Oxoid Preparation:
Suspend 10g in 100ml of distilled water (or 1g amounts in 10ml volumes of water in tubes). Allow to stand for 15 minutes until the meat particles are thoroughly wetted. Sterilise by autoclaving at 121°C for 15 minutes. Do not cool the bottles rapidly because ebullition will expel the meat particles from the containers.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium at room temperature, in the dark with tightened caps for up to 6 months.

Precautions
The excellent recovery properties of Cooked Meat Medium mean that mixed cultures commonly result from sample inoculation.
Blackening of the medium will not take place if the pH is acid.
Carbohydrate fermentation may inhibit proteolysis.

Detect thermophilic anaerobic organisms causing sulphide spoilage in food with Thermo Scientific™ Oxoid™ Iron Sulphite Agar (Dehydrated). The medium is a modification of Cameron Sulphite Agar developed by the National Canners Association of America1. Iron Sulphite Agar has a reduced concentration of sodium sulphite to allow improved detection of some strains of Clostridium sporogenes.

Iron Sulphite Agar, Oxoid Composition

Iron Sulphite Agar, Oxoid Preparation:
Suspend 23.0g in 1 litre of distilled water and boil to dissolve completely. Sterilise by autoclaving for 15 minutes at 121°C. Mix well before pouring.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium below 25°C.

Precautions
The blackening reaction is only presumptive evidence of clostridial growth. Confirmation tests must be carried out to identify the organism growing in the medium.

Oxoid Dextrose Tryptone Agar is used for detection and enumeration of thermophilic and mesophilic microorganisms in food.

Dextrose Tryptone Agar, Oxoid Composition

Dextrose Tryptone Agar, Oxoid Preparation:
Suspend 27g in 1 litre of distilled water and bring to the boil to dissolve completely. Sterilise by autoclaving at 121°C for 15 minutes.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared agar plates at 2-8°C.

Precautions
Incubation at 55°C must be carried out under humid conditions e.g. wrapped dishes or in a high humidity environment.

Oxoid Dextrose Tryptone Broth is used for detection and enumeration of thermophilic and mesophilic microorganisms in food.

Dextrose Tryptone Broth, Oxoid Composition

Dextrose Tryptone Broth, Oxoid Preparation:
Add 15g to 1 litre of distilled water. Mix well and distribute into final containers. Sterilise by autoclaving at 121°C for 15 minutes.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared broth below 25°C.

Oxoid Urea Broth Base (Christensen Broth Base) is used for the detection of urease producing microorganisms.

Urea Broth Base, Oxoid Composition

Urea Broth Preparation:
Add 0.9 g to 95 ml of distilled water. Sterilise by autoclaving at 115°C for 20 minutes. Cool to 55°C and aseptically introduce 5 ml of sterile 40% Urea Solution SR0020. Mix well and distribute 10 ml amounts into sterile containers.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium at 2-8°C.

Precautions
It is preferable that the medium be used on the day of preparation. If not, examine the tubes carefully to ensure sterility.
After overnight incubation other members of the Enterobacteriaceae may show alkaline reactions.

Detect, enumerate and differentiate the members of coliform group with Thermo Scientific™ Oxoid™ Eosin Methylene Blue Agar (Modified) Levine (Dehydrated). This versatile medium, modified by Levine is used for the differentiation of Escherichia coli and Enterobacteria aerogenes and also for rapid identification of Candida albicans. The medium is prepared to the formula specified by the APHA for the detection and differentiation of the coliform group of organisms.

Eosin Methylene Blue Agar (Modified) Levine, Oxoid Composition

Eosin Methylene Blue Agar (Modified) Levine, Oxoid Preparation:
Suspend 37.5g in 1 litre of distilled water. Bring to the boil to dissolve completely. Sterilise by autoclaving at 121°C for 15 minutes. Cool to 60°C and shake the medium in order to oxidise the methylene blue (i.e. restore its blue colour) and to suspend the precipitate which is an essential part of the medium.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared plates at 2-8°C away from light.

Precautions
Further tests are required to confirm the presumptive identity of organisms isolated on this medium. Some strains of Salmonella and Shigella species will not grow in the presence of eosin and methylene blue. Store the medium away from light to prevent photo-oxidation.

Cultivate fastidious pathogens and other microorganisms with nutritious Thermo Scientific™ Oxoid™ Nutrient Broth No.2 (Dehydrated). This medium is comparable to a meat infusion and is richer in nutrients than Nutrient Broth (CM0001). It gives good growth from small inocula and is recommended for sterility testing for aerobic organisms. It complies with the recommendations in the ‘British Pharmacopoea’ for the composition of a sterility testing medium for aerobes.

Nutrient Broth No.2, Oxoid Composition

Nutrient Broth No.2, Oxoid Preparation:
Add 25g to 1 litre of distilled water. Mix well, distribute into final containers and sterilise by autoclaving at 121°C for 15 minutes.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium at 2-8°C.

This product has been discontinued. The alternative to this product is Peptone Water.

Oxoid Peptone Water Andrade’s is a nutrient base containing Andrade’s indicator to which carbohydrates and other diagnostic reagents may be added for use in fermentation studies.

Peptone Water Andrade’s, Oxoid Composition

Peptone Water Andrade’s, Oxoid Preparation:
Suspend 15 g in 1 litre of distilled water. Mix well to dissolve, distribute into tubes or bottles, containing Durham tubes and sterilize by autoclaving at 121°C for 15 minutes.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium in the dark at room temperature.

Detect, isolate and enumerate yeasts and molds with Thermo Scientific™ Oxoid™ Malt Extract Agar (Dehydrated). Mycological peptone in the medium gives a luxuriant growth of yeasts and molds with typical morphology and pigmentation.

Malt Extract Agar, Oxoid Composition

Malt Extract Agar, Oxoid Preparation:
Suspend 50g in 1 litre of distilled water and boil to dissolve. Sterilise by autoclaving at 115°C for 10 minutes.

If it is desired to adjust the medium to pH 3.5, cool to 55°C and add approximately 2-3ml of 10% Lactic Acid SR0021 to 100ml Malt Extract Agar. Once acidified with lactic acid, the medium should not be re-heated.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium at 2-8°C.

Oxoid Malt Extract Broth is used for the identification of yeast and molds in sterility testing.

Malt Extract Broth, Oxoid Composition

Malt Extract Broth, Oxoid Preparation:
Add 20g to 1 litre of distilled water. Mix well, distribute into final containers and sterilise by autoclaving at 115°C for 10 minutes. This liquid medium is recommended for the cultivation of moulds and yeasts, during tests for sterility, etc.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium at 2-8°C.

Oxoid Blood Agar Base is a nonselective general purpose medium which may be enriched with blood or serum.

Blood Agar Base, Oxoid Composition

Blood Agar Base, Oxoid Preparation:
Suspend 40g in 1 litre of distilled water. Bring to the boil to dissolve completely. Sterilise by autoclaving at 121°C for 15 minutes.

For blood agar, cool the Base to 50°C and add 7% of Defibrinated Horse Blood SR0050. Mix with gentle rotation and pour into petri dishes or other containers.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared plates of medium at 2-8°C.

Precautions
The haemolytic reactions of organisms inoculated on to this medium will be affected by the animal blood used e.g. horse or sheep and the incubation conditions e.g. aerobic, capnoeic or anaerobic.
When horse blood is added to the medium Haemophilus haemolyticus colonies will produce beta-haemolysis and mimic Streptococcus pyogenes.

Oxoid Urea Agar Base (Christensen Agar Base) is used for detection of urease-producing microorganisms.

Urea Agar Base, Oxoid Composition

Urea Agar Preparation:
Suspend 2.4g in 95ml of distilled water. Bring to the boil to dissolve completely. Sterilise by autoclaving at 115°C for 20 minutes. Cool to 50°C and aseptically introduce 5ml of sterile 40% Urea Solution SR0020. Mix well, distribute 10ml amounts into sterile containers and allow to set in the slope position.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium at 2-8°C.

Precautions
The alkaline reaction produced in this medium after prolonged incubation may not be caused by urease activity. Check using medium without urea.
Do not heat or reheat the medium because urea decomposes very easily.
For the detection of urease-positive Proteae the reaction must be read within the first 2-5 hours of incubation.

Oxoid MRVP Medium. A glucose-phosphate medium is used for the differentiation of the coli-aerogenes group by the Methyl Red and Voges-Proskauer tests.

MRVP Medium, Oxoid Composition

MRVP Medium, Oxoid Preparation:
Add 17g to 1 litre of distilled water. Mix well, distribute into final containers and sterilise by autoclaving at 121°C for 15 minutes.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium at 2-6°C.

Precautions
The MR-VP reactions are only part of the tests required to identify organisms.
Each laboratory should standardise on the inoculum density, volume of broth and the test container size.
MR tests require a minimum incubation of 48 hours before the pH indicator is added.
When using Barritt’s reagents add a-naphthol first and KOH second; do not reverse this order.
Vaughn et al. warned of false positive VP reactions if the completed tests are left standing for over an hour.

Identify dermatophytes and other fungi and yeasts in clinical specimens and environmental samples with the acidic Thermo Scientific™ Oxoid™ Sabouraud Dextrose Agar. The low pH supports the growth of fungi while inhibiting bacterial growth in mixed samples. Fungi maintain their typical cultural appearance and, thus, may be readily identified according to standard macroscopic characters.

Directions
Add 65g of Sabouraud Dextrose Agar to 1L of distilled water. Sterilize the medium by autoclaving at 121°C for 15 mins. Mix well and pour into a clean petri dish.

Storage Conditions and Shelf Life
Store the medium at 10-30°C and use before the expiry date printed on the label. Store the prepared medium at 2-8°C.

Oxoid Desoxycholate Citrate Agar is a differential medium for enumeration of coliforms and the isolation of enteric pathogens.

Desoxycholate Citrate Agar, Oxoid Composition

Desoxycholate Citrate Agar, Oxoid Preparation:
Suspend 48.5g in 1 litre of distilled water. With frequent agitation bring to the boil over a gauze and flame to dissolve completely. Mix well and pour plates immediately. Dry the agar surface before use.

THIS MEDIUM IS HEAT SENSITIVE. AVOID EXCESSIVE OR PROLONGED HEATING DURING RECONSTITUTION. DO NOT AUTOCLAVE, OR REMELT.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared agar plates at 2-8°C.

Precautions
The medium is best used freshly prepared.
Stock cultures of Shigella species may become predominantly in the R-phase when subcultured away from DCA media. Such cultures are difficult to use for control purposes without first heavily streaking the cultures on DCA plates and picking off the few S-phase colonies i.e. the macro-colonies on the agar surface, for further subculture.
When making biochemical tests on colonies picked from the surface of DCA plates, purity subcultures should be carried out because the colony may be contaminated with Escherichia coli present as micro-colonies.

Oxoid Kligler Iron Agar is used for differential identificaton of Enterobacteriaceae.

Kligler Iron Agar, Oxoid Composition

Kligler Iron Agar, Oxoid Preparation:
Suspend 55g in 1 litre of distilled water. Bring to the boil to dissolve completely. Mix well and distribute into containers. Sterilise by autoclaving at 121°C for 15 minutes. Allow to set as slopes with 1 inch butts.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium at 2-8°C.

Precautions
It is essential that Kligler Iron Agar is examined and reported at 18-24 hours. Early or late readings will give false results.
KIA will grow both oxidative and fermentative organisms. Confusion will result if care is not taken to distinguish between the two groups.
Always use a straight wire to inoculate the butt, to avoid splitting the agar with a loop.
Pure cultures are essential to avoid misinterpretation.
Do not use screw-capped tubes or bottles for KIA medium. It is essential that air is freely available to growth on the slant.

Oxoid Brilliant Green Bile Broth 2% is used for detection or confirmation of presence of members of coli-aerogenes group.

• Recommended for 44°C confirmatory test for Escherichia coli

Brilliant Green Bile Broth 2%, Oxoid Composition

Brilliant Green Bile Broth 2%, Oxoid Preparation:
Dissolve 40g in 1 litre of distilled water. Mix well, distribute into containers fitted with Durham’s tubes and sterilise by autoclaving at 121°C for 15 minutes.

Do not autoclave double stregnth medium. The alternative procedure is to heat the dissolved broth at 100°C for 30 minutes.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared tubes of broth at 2-8°C.

Precautions
Do not autoclave double-strength broth.
Gram-positive sporing organisms may produce gas if the bile/brilliant green inhibition is attenuated by food material.

Oxoid Tetrathionate Broth Base is used for selective enrichment of Salmonella species.

Tetrathionate Broth Base, Oxoid Composition
Add 77g to 1 litre of distilled water and bring to the boil. Cool below 45°C and add 20ml of iodine solution. Mix well and tube in 10ml quantities. The prepared base will keep for several weeks at 4°C but should be used soon after the addition of the iodine solution.

Iodine Solution

Tetrathionate Broth Preparation:
Tetrathionate Broth is recommended for the selective enrichment method of isolating Salmonella typhi and other salmonellae from faeces, sewage, etc.

Organisms which reduce tetrathionate, such as salmonellae, flourish in the medium whilst many faecal organisms are inhibited. Members of the Proteus group reduce tetrathionate and may consequently impair the value of this medium for the isolation of salmonellae; this disadvantage of the medium is largely overcome by the addition of 40µg of novobiocin to each millilitre of the incomplete medium before the addition of iodine.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium (without iodine solution) at 2-8°C.