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Oxoid Potassium Tellurite (3.5%) is a solution for addition to culture media.

Ordering Information:

Supplied 2mL/vial

Isolate and enumerate yeasts and molds from dairy and food products and prepare Aspergillus niger for the Harmonised Microbial Limit Tests from international pharmacopoeia with Thermo Scientific™ Oxoid™ Potato Dextrose Agar (Dehydrated). This medium is suitable for the detection and enumeration of heat resistant molds in thermally processed fruits and fruit products.

Pigment production is a critical part of the identification of the fungus. The agar used in the medium is carefully screened to ensure correct pigment production by fungi such as Fusaria spp.

Composition of Potato Dextrose Agar

Preparation of Potato Dextrose Agar, Oxoid
Suspend 39g in 1 litre of purified water and heat up to dissolve completely. Sterilise by autoclaving at 121°C for 15 minutes. Ensure the solution is well mixed before pouring.

To suppress the growth of bacteria, you can acidify the medium to pH 3.5 by adding 1 ml of lactic acid 10% SR0021 to each sterilized medium at 50°C. Note that the medium must not be heated after the addition of acid as it will destroy the gelling properties and results in hydrolysis of agar.

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.

Thermo Scientific™ Oxoid Potato Dextrose Broth is a general broth for yeasts and molds.

Isolate and enumerate yeasts and molds associated with food spoilage with Thermo Scientific™ Oxoid™ Pre-supplemented Dichloran-Glycerol 18% (DG18) (ISO) Agar Base (Dehydrated) while adhering to BS ISO 21527-2: 2008. Due to the presence of antibiotic Chloramphenicol in the formulation, the medium provides selectivity against bacteria as well as reducing harmful chemical handling in the laboratory.

Pre-supplemented Dichloran-Glycerol 18% (DG18) (ISO) Agar Base (Dehydrated), Oxoid Composition

Pre-supplemented Dichloran-Glycerol 18% (DG18) (ISO) Agar Base, Oxoid Preparation:
Suspend 15.8g per 500ml (31.6g/l) of distilled water and heat to dissolve completely. Before autoclaving add 220g of Glycerol per 1 litre of medium. Heat the complete solution gently to aid its dissolution of the glycerol. This has been found to be a key procedure to follow to allow proper dissolution of the glycerol. Sterilize by autoclaving at 121°C for 15 minutes. Cool to 50°C, mix well and pour into sterile Petri dishes.

Where bacterial overgrowth occurs from certain foods (raw meats) chlortetracycline hydrochloride at 50mg/L (dissolved in water and filter sterilised) is recommended.

Storage instructions
Store the dehydrated medium at 10–30°C and use before the expiry date.

Precautions
The dichloran compound used in this medium is Botran® 2,6-Dichloro-4-Nitro-Analine (CAS: 99-30-9).

Pre-supplemented DG18 (ISO) Agar (CM1151) contains Chloramphenicol in the base powder and is therefore considered a toxic compound which should be handled in accordance with good industrial hygiene and safety practice. Always consult the MSDS before handling the powder.

Isolate and enumerate yeasts and molds associated with food spoilage with Thermo Scientific™ Oxoid™ Pre-supplemented Dichloran Rose-Bengal Chloramphenicol (DRBC) (ISO) Agar Base (Dehydrated) while adhering to ISO 21527-1: 2008. Due to the presence of antibiotic Chloramphenicol in the formulation, the medium provides selectivity against bacteria as well as reducing harmful chemical handling in the laboratory.

Pre-supplemented Dichloran Rose-Bengal Chloramphenicol (DRBC) (ISO) Agar Base (Dehydrated), Oxoid Composition

Pre-supplemented Dichloran Rose-Bengal Chloramphenicol (DRBC) (ISO) Agar, Oxoid Preparation:
Suspend 15.75g per 500ml (31.5g/l) of distilled water and heat to dissolve completely. Sterilize by autoclaving at 121°C for 15 minutes. Cool to 50°C, mix well and pour into sterile Petri dishes. It is advised to dispense the powdered medium into containers under an extraction hood due to the chloramphenicol in the medium base.

Storage instructions
Store the dehydrated medium at 10–30°C and use before the expiry date

Precautions
ROSE-BENGAL PHOTO-OXIDIZES TO FORM TOXIC COMPOUNDS. STORE PLATES OF THE MEDIUM IN THE DARK AND AVOID EXPOSURE TO LIGHT.
Some strains of fungi may be inhibited on this medium.
The dichloran compound used in this medium is Botran® 2,6-Dichloro-4-Nitro-Analine (CAS: 99-30-9).

Pre-supplemented DRBC (ISO) Agar (CM1149) contains Chloramphenicol in the base powder and is therefore considered a toxic compound which should be handled in accordance with good industrial hygiene and safety practice. Always consult the MSDS before handling the powder.

This product has been discontinued. The recommended alternative is Modified Preston Campylobacter Supplement, SR0204E.

Oxoid Preston Campylobacter Selective Supplement is used for the isolation of Campylobacter jejuni and Campylobacter coli from human, animal, avian, and environmental samples.

• Add to Campylobacter Agar Base, Part No. CM0689B or Nutrient Broth No. 2, Part No. CM0067B
• Each vial supplements 500mL of medium

Preston Campylobacter Selective Supplement, Oxoid Composition

Preston Campylobacter Selective Agar, Oxoid Preparation:
Suspend 18.5g of Campylobacter Agar Base in 475ml of distilled water and bring to the boil to dissolve completely. Sterilise by autoclaving at 121°C for 15 minutes. Cool to 50°C. Aseptically add 25ml of Lysed Horse Blood (SR0048), and 1 vial of Preston Campylobacter Selective Supplement (SR0117 or SR0204) reconstituted as directed and one vial of Campylobacter Growth Supplement (SR0232). Mix well and pour into sterile Petri dishes.

Preston Campylobacter Selective Enrichment Broth, Oxoid Preparation:
Dissolve 12.5g of Nutrient Broth No.2 (CM0067) in 475ml of distilled water and sterilise by autoclaving at 121°C for 15 minutes. Cool to 50°C or below. Aseptically add 25ml of Lysed Horse Blood (SR0048), 1 vial of Preston Campylobacter Selective Supplement (SR0117 or SR0204) and 1 vial of Campylobacter Growth Supplement (SR0232). Aseptically dispense 5ml volumes in sterile small screw-capped bottles. The Selective Enrichment Broth may be stored for up to 7 days at 2-8°C.

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 Proteose Peptone is a speciality peptone containing proteoses as defined in the USP.

• Particularly suitable for use in toxin production and in culture media for bacteria with wide-ranging nutritional requirements

Selectively isolate Pseudomonas species from a range of samples with Thermo Scientific™ Oxoid™ Pseudomonas Agar Base (Dehydrated). The medium is modification of King’s A Medium and contains magnesium chloride and potassium sulphate for improved pigment production and recovery of Pseudomonas aeruginosa while strongly suppressing Klebsiella, Proteus and Providencia spp.

Pseudomonas Agar Base (Dehydrated), Oxoid Composition

Agar Preparation:
To Prepare the Agar Base:
Suspend 24.2g of the agar base, in 500ml of distilled water. Add 5ml of glycerol. Bring to the boil to dissolve completely, sterilise by autoclaving at 121°C for 15 minutes. Allow the medium to cool to 50°C.

To Prepare Pseudomonas CN Agar:
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.

To Prepare Pseudomonas CFC Agar:
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 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 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.