Microbiology

For the preparation of serum-dextrose-antibiotic medium for the cultivation and isolation of Brucella using Brucella Selective Supplement SR0083 or SR0209. Without antibiotics, it may be used in conjunction with the Cruickshank dyestrip method for differentiation between strains.

Brucella Medium Base, Oxoid Composition

Brucella Medium, Oxoid Preparation:
Suspend 45 g in 1 litre of distilled water. Bring to the boil to dissolve completely. Sterilise by autoclaving at 121°C for 15 minutes. Cool to 50°C and add 5% of inactivated Horse Serum (i.e. Horse Serum held at 56°C for 30 minutes). 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 agar plates at 2-8°C.

• Oxoid WL Nutrient Agar is used for the determination of the microbiological flora in brewing and fermentation processes.
• Also available Cycloheximide 0.1% Solution, Part No. SR0222C.

WL Nutrient Agar, Oxoid Composition

WL Nutrient Agar, Oxoid Preparation:
Suspend 75g in 1 litre of distilled water. Bring to the boil to dissolve completely. Sterilise by autoclaving at 121°C for 15 minutes. If required the pH may be adjusted to 6.5 by the addition of 1% sodium bicarbonate solution.

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
When handling cycloheximide observe the precautions to be taken under HAZARDS.

Oxoid C-F-C Supplement is used for the isolation of Pseudomonas species.

• Add to to Pseudomonas Agar Base, Part No. CM0559B
• Each vial supplements 500mL of medium

Pseudomonas CFC Supplement, Oxoid Composition

Pseudomonas CFC Agar, Oxoid Preparation:
To 500ml of agar base cooled to 50°C add the contents of 1 vial of Pseudomonas CFC Supplement (SR0103) rehydrated as directed. Mix well and pour into sterile Petri dishes.

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
Fresh media should be prepared as required. Molten agar should not be kept longer than 4 hours. Medium should not be stored and remelted. If swarming colonies of Proteus species are a problem in food samples then the incubation temperature can be lowered to 20°C for a period of 3-5 days. Chilled foods may carry a wide range of pseudomonads and the colonies on CFC Medium, incubated at lower temperatures, may be Pseudomonas fluorescens or Pseudomonas putida as well as Pseudomonas aeruginosa. Aeromonas species will also appear as pink/brown colonies, particularly from fish products.

Oxoid Yeast Extract Powder is a dried yeast autolysate which provides a nutritious source of nitrogen and vitamins.

• Recommended for plate count of organisms in water
• Increases yield of organisms of many media or fermentation broths

Oxoid C-N Supplement is used for the isolation of Pseudomonas aeruginosa.

• Add to to Pseudomonas Agar Base, Part No. CM0559B
• Each vial supplements 500mL of medium

Pseudomonas CN Supplement, Oxoid Composition

Pseudomonas CN Agar, Oxoid Preparation:
To 500ml of agar base cooled to 50°C add the contents of 1 vial of Pseudomonas CN Supplement (SR0102) rehydrated as directed. Mix well and pour into sterile Petri dishes.

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
Fresh media should be prepared as required. Molten agar should not be kept longer than 4 hours. Medium should not be stored and remelted. If swarming colonies of Proteus species are a problem in food samples then the incubation temperature can be lowered to 20°C for a period of 3-5 days. Chilled foods may carry a wide range of pseudomonads and the colonies on CFC Medium, incubated at lower temperatures, may be Pseudomonas fluorescens or Pseudomonas putida as well as Pseudomonas aeruginosa. Aeromonas species will also appear as pink/brown colonies, particularly from fish products.

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.

Selectively enrich Salmonella spp. from food and environmental specimens with Thermo Scientific™ Oxoid™ Rappaport-Vassiliadis Soya Peptone Broth (Dehydrated). Rappaport- Vassiliadis Soya Peptone Broth selects for Salmonella species by exploiting their characteristics when compared with other Enterobacteriaceae, such as the ability to survive at relatively high osmotic pressure, multiply at relatively low pH values, be relatively more resistant to malachite green, and have relatively less demanding nutritional requirements.

Rappaport-Vassiliadis Soya Peptone Broth (Dehydrated), Oxoid Composition

Rappaport-Vassiliadis Soya Peptone Broth (Dehydrated), Oxoid Preparation:
Suspend 26.75g in 1 litre of distilled water and heat gently to dissolve. Dispense 10ml volumes into screw-capped bottles or tubes and sterilise by autoclaving at 115°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.

Precautions
RVS Broth should not be used if Salmonella Typhi is suspected.
In order to achieve optimum recovery it is recommended that the enrichment broth is incubated at 42 ± 1°C.

Detect and enumerate coliform organisms in water, food and dairy products with Thermo Scientific™ Oxoid™ Violet Red Bile Agar (Dehydrated). This lactose containing selective medium has been used for the determination of the coli-aerogenes content of water, milk and other dairy products, dairy equipment, and food products. Due to the addition of selective inhibitory components, neutral red, crystal violet, and bile salts, the medium provides selectivity against non-target Gram-positive bacteria.

Violet Red Bile Agar (Dehydrated), Oxoid Composition

Violet Red Bile Agar (Dehydrated), Oxoid Preparation:
Suspend 38.5g in 1 litre of distilled water. Bring to the boil. Continue to boil for 2 minutes or for the minimum time necessary to dissolve completely and ensure that there are no remaining flecks of unmelted agar. No further sterilisation is necessary or desirable. 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 at 2-8°C and use as freshly as possible.

Precautions
This medium is not completely specific for Enterobacteriaceae, other organisms e.g. Aeromonas and Yersinia species may give similar reactions.
The selectivity of the medium diminishes after 24 hours incubation and organisms previously suppressed may exhibit growth.

Thermo Scientific™ Oxoid Standard Plate Count Agar (Plate Count Agar) is a standard medium corresponding to the APHA formulation used for milk, food and dairy products.

Standard Plate Count Agar (Plate Count Agar), Oxoid Composition

Standard Plate Count Agar (Plate Count Agar), Oxoid Preparation:
Suspend 23.5g in 1 litre of distilled water. Bring to the boil to dissolve completely. Dispense into bottles 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 plates at 2-8°C.

Cultivate and isolate fastidious pathogens and other microorganisms with Thermo Scientific™ Oxoid™ Blood Agar Base No. 2 (Dehydrated). The specially designed formulation meets the need for a nutritious blood agar which permits maximum recovery of delicate organisms without interfering with their hemolytic reactions. Without any additions, the medium can be used for short-term maintenance of stock cultures. And with the addition of blood, the medium becomes suitable for the determination of the hemolytic reactions which are important diagnostic criteria for many organisms.

Blood Agar Base No. 2, Oxoid Composition

Blood Agar Base No. 2, 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. Cool to 45-50°C and add 7% sterile blood.

Mix with gentle rotation and pour into sterile 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
Brucella cultures are highly infective and must be handled under properly protected conditions. Incubate in 5-10% carbon dioxide atmosphere for 24-48 hours.

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.

Thermo Scientific™ Oxoid Mannitol Selenite Broth Base is a modification of Selenite F Broth for the selective enrichment of salmonellae.

Mannitol Selenite Broth Base, Oxoid Composition

Mannitol Selenite Broth, Oxoid Preparation:
Add 19g to 1 litre of distilled water to which 4g of sodium biselenite LP0121 has been added.
Warm to dissolve, mix well and fill out into containers. Sterilise in a boiling water bath, or in free flowing steam, for 10 minutes.
DO NOT AUTOCLAVE.

To minimise any possible risk of teratogenicity to laboratory workers, the sodium biselenite must be added to this medium separately.

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 away from light.

Differentiate Enterobacteriaceae according to their ability to ferment lactose, sucrose, and glucose, and to produce hydrogen sulphide using Thermo Scientific™ Oxoid™ Triple Sugar Iron Agar (Dehydrated). The Triple Sugar Iron Agar is based on Kligler Iron Agar, additionally, it contains sucrose for the detection of sucrose fermenting species.

Triple Sugar Iron Agar, Oxoid Composition

Triple Sugar Iron Agar, Oxoid Preparation:
Suspend 65g in 1 litre of distilled water. Bring to the boil to dissolve completely. Mix well and distribute. Sterilise by autoclaving at 121°C for 15 minutes. Allow the medium to set in sloped form with a butt about 1 in.deep.

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.

Detect and enumerate coliform organisms, including Escherichia coli, while isolating and detecting Salmonella and Shigella spp. in both clinical and food specimens using Thermo Scientific™ Oxoid™ MacConkey Agar No.3. A modification of the original MacConkey medium by the addition of selected bile salts, the medium gives improved differentiation of coliforms and non-lactose fermenting organisms while completely inhibiting Gram-positive cocci.

MacConkey Agar No.3, Oxoid Composition

MacConkey Agar, Oxoid Preparation:
Suspend 51.5g in 1 litre of distilled water. Bring to the boil to dissolve completely. Sterilise by autoclaving at 121°C for 15 minutes.

Storage conditions and Shelf life
The dehydrated medium should be stored at 10-30°C and used 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.

Selectively enrich Cronobacter spp. from milk and milk samples using Thermo Scientific™ Oxoid™ Modified Lauryl Sulphate Tryptose Broth Base (Dehydrated). Modified Lauryl Sulphate Tryptose Broth Base was originally described by Guillaume-Gentil et al. for the selective enrichment of Cronobacter spp. The high salt concentration of the medium restricts the growth of other members of Enterobacteriaceae and the combination of vancomycin and sodium lauryl sulphate inhibits the growth of Gram-positive organisms commonly isolated in production environments.

Modified Lauryl Sulphate Tryptose Broth Base, Oxoid Composition

Modified Lauryl Sulphate Tryptose Broth, Oxoid Preparation:
Dissolve 32.3g in 500ml of distilled water. Sterilize by autoclaving at 121°C for 15 minutes. Cool to approximately 50°C, and aseptically add the contents of 1 vial of Vancomycin Supplement (5mg) (SR0247E) reconstituted as directed. Mix well and aseptically dispense 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
Where possible the complete medium should be prepared on the day of testing and stored for no longer than 1 day at 0-5ºC

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.

Identify coliforms from water and milk samples with differential Thermo Scientific™ Oxoid™ MacConkey Broth (Dehydrated). MacConkey Broth is the standard medium for the primary isolation of coliform bacteria, and has been recommended for this purpose by the Public Health Laboratory Service Water Committee and the World Health Organization. MacConkey Broth also conforms to the formulation specified by the UK Dept. of Health for milk grading.

MacConkey Broth, Oxoid Composition

MacConkey Broth, Oxoid Preparation:
To prepare single strength broth, add 40g to 1 litre of distilled water. Mix well and distribute into containers fitted with fermentation (Durham) tubes. 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.

Precautions
The neutral red indicator is carefully selected for this formulation and therefore shows no inhibitory effect. However, the more sensitive reaction of bromocresol purple in MacConkey Broth Purple (CM0505) is often preferred.

Determine the plate counts of microorganisms in food, dairy samples, waste water and other material of sanitary importance with Thermo Scientific™ Oxoid™ Plate Count Agar (Dehydrated). Plate Count Agar was developed by Buchbinder et al which is recommended by APHA, AOAC and PHLS. The quality control of Plate Count Agar (APHA) includes testing in accordance with ISO 11133:2014.

Plate Count Agar (Dehydrated), Oxoid Composition

Plate Count Agar (Dehydrated), Oxoid Preparation:
Add 17.5g to 1 litre of distilled water. Dissolve by bringing to the boil with frequent stirring, mix 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 plates at 2-8°C.

Isolate Salmonella and Shigella from clinical specimens and foods with selective Thermo Scientific™ Oxoid™ XLD Agar (Dehydrated). The medium relies on xylose fermentation, lysine decarboxylation and production of hydrogen sulphide for the primary differentiation of shigellae and salmonellae from non-pathogenic bacteria. The careful addition of sodium desoxycholate inhibits the growth of coliforms without decreasing the ability to support shigellae and salmonellae.

XLD Agar (Dehydrated), Oxoid Composition

XLD Agar (Dehydrated), Oxoid Preparation:
Suspend 53g in 1 litre of distilled water. Heat with frequent agitation until the medium boils. DO NOT OVERHEAT. Transfer immediately to a water bath at 50°C. Pour into sterile Petri dishes as soon as the medium has cooled.

It is important to avoid preparing large volumes which will cause prolonged heating.

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.

Presumptively identify coliform organisms in milk, water and foods as specified by the American Public Health Association with Thermo Scientific™ Oxoid™ Lactose Broth (Dehydrated). Beef extracts and peptone in this liquid medium supply essential nutrients while lactose is a fermentable carbohydrate for coliforms. Coliforms ferment lactose in the medium resulting in gas formation which is indicative of positive results.

Lactose Broth, Oxoid Composition

Lactose Broth, Oxoid Preparation:
Dissolve 13g in 1 litre of distilled water and distribute into containers with fermentation tubes (Durham). 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 (18-22°C).

Precautions
Ensure that the fermentation tubes are free from air bubbles before inoculation.
Large water samples may require double-strength lactose broth to reduce the final volumes. Do not overheat double- strength broth or inhibitory products will be produced.

Selectively isolate pathogenic Vibrio species with Thermo Scientific™ Oxoid™ TCBS (Thiosulfate Citrate Bile Salts Sucrose) Cholera Medium (Dehydrated). The medium has shown to be the most satisfactory and reproducible formula regardless of the complex composition. Unlike Lauryl Sulphate Tellurite Agar it does not require further additives or aseptic additions of blood. It also possesses superior growth characteristics for Vibrio species, compared with tellurite media. While inhibiting non-vibrios, it promotes rapid growth of pathogenic vibrios after overnight incubation at 35°C.

TCBS (Thiosulfate Citrate Bile Salts Sucrose) Cholera Medium (Dehydrated), Oxoid Composition

TCBS (Thiosulfate Citrate Bile Salts Sucrose) Cholera Medium (Dehydrated), Oxoid Preparation:
Suspend 88g in 1 litre of distilled water. Boil to dissolve the medium completely. DO NOT AUTOCLAVE.
Pour plates without further heating and dry before use.

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 identification of the various Vibrio species on TCBS Medium is presumptive and further tests are required for confirmation.
Yellow colonies on TCBS Medium will give unsatisfactory oxidase reactions.
Colonies taken from TCBS Medium are `sticky’ and react poorly in slide agglutination tests. Subculture to nutrient agar is required before slide agglutination tests can be carried out.
Some strains of Vibrio vulnificus produce better recovery at 30°C.

Oxoid Casein Hydrolysate (Acid) is a purified hydrolysate which provides the necessary nitrogenous material for culture media or can be used when amino acid mixtures are specified.

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.