Intended Use

A basal medium which; with carbohydrate addition is used to study fermentation reactions.

Composition

Ingredients	Gms / Litre
Peptone	10.000
Sodium chloride	5.000
Andrade indicator	0.100
Final pH (at 25°C)	7.4±0.2

**Formula adjusted, standardized to suit performance parameters

Directions

Suspend 15.1 grams in 1000 ml purified / distilled water. Heat if necessary to dissolve the medium completely and dispense in test tubes containing inverted Durhams tubes. Sterilize by autoclaving at 15 lbs pressure (121°C) for 15 minutes. Cool to room temperature and aseptically add sterile stock solution of carbohydrate to a final concentration of 0.5% to 1.0% (w/v).

Principle And Interpretation

Bacteria differ widely in their ability to metabolize carbohydrates and related compounds. Carbohydrate fermentation reactions aids in the differentiation and identification of various bacteria. Andrade Peptone Water is the most commonly used media for carbohydrate fermentation (5). Desired carbohydrate is added to the medium, which is inoculated with the test organism. If the test organism metabolizes the added carbohydrate, acids are produced, thereby lowering the pH of the medium. This causes a subsequent colour change of the indicator, from colourless to pink to red. If the added carbohydrate is not metabolized, the medium remains pale tan to straw coloured. Gas produced during fermentation is collected in the Durhams tube.

The peptone used in the medium is free from fermentable carbohydrates (1,5) and the medium is also free from nitrates which may interfere with gas production. Andrade indicator is a solution of acid fuchsin which when titrated with sodium hydroxide; changes colour from pink to yellow. The Andrade indicator changes colour from yellow to pink as the pH decreases (5). The medium is pink when hot but becomes straw coloured on cooling. Test carbohydrate solutions should be sterilized separately and aseptically added to sterile Andrade Peptone Water. Use fresh cultures of organisms only which have been presumptively identified by Gram staining and colony morphology. The biochemical identification of organisms capable of growing in this medium is made by various sugar fermentation results (1,2,6).

Type of specimen

Food samples, Pure isolate

Specimen Collection and Handling

For food samples, follow appropriate techniques for sample collection and processing as per guidelines (7).

After use, contaminated materials must be sterilized by autoclaving before discarding.

Warning and Precautions

Read the label before opening the container. Wear protective gloves/protective clothing/eye protection/ face protection. Follow good microbiological lab practices while handling specimens and culture. Standard precautions as per established guidelines should be followed while handling specimens. Safety guidelines may be referred in individual safety data sheets

Limitations

Fresh cultures should be used to avoid errorneous results.
For final identification further biochemical tests are required.

Performance and Evaluation

Performance of the medium is expected when used as per the direction on the label within the expiry period when stored at recommended temperature.

Quality Control

Appearance
Cream to yellow coloured with pink tinge, homogeneous free flowing powder

Colour and Clarity of prepared medium
Light pink to straw coloured clear solution without any precipitate

Reaction
Reaction of 1.51% w/v aqueous solution at 25°C. pH: 7.4±0.2

Cultural response

Cultural characteristics observed after an incubation at 35-37°C for 18-24 hours.

Organism	Inoculum (CFU)	Growth	Acid in absence of dextrose	Gas in absence of dextrose	Acid with added dextrose	Gas with added dextrose
Escherichia coli ATCC 25922 (00013*)	50-100	luxuriant	negative reaction	negative reaction	positive reaction, colour reaction changes to pink red	positive
Klebsiella pneumoniae ATCC 13883 (00097*)	50-100	luxuriant	negative reaction	negative reaction	positive reaction, colour reaction changes to pink red	positive
Proteus vulgaris ATCC 13315	50-100	luxuriant	negative reaction	negative reaction	positive reaction, colour reaction changes to pink red	positive
Salmonella Typhi ATCC 6539	50-100	luxuriant	negative reaction	negative reaction	positive reaction, colour reaction changes to pink red	negative
Salmonella Typhimurium ATCC 14028 (00031*)	50-100	luxuriant	negative reaction	negative reaction	positive reaction, colour reaction changes to pink red	positive
Shigella flexneri ATCC 12022 (00126*)	50-100	luxuriant	negative reaction	negative reaction	positive reaction, colour reaction changes to pink red	negative
Shigella sonnei ATCC 25931	50-100	luxuriant	negative reaction	negative reaction	positive reaction, colour reaction changes to pink red	negative

Key: (*) Corresponding WDCM numbers.

Storage and Shelf Life

Store between 10-30°C0in a tightly closed container and the prepared medium at 15-25°C. Use before expiry date on the label. On opening, product should be properly stored dry, after tightly capping the bottle inorder to prevent lump formation due to the hygroscopic nature of the product. Improper storage of the product may lead to lump formation. Store in dry ventilated area protected from extremes of temperature and sources of ignition Seal the container tightly after use. Product performance is best if used within stated expiry period.

Disposal

User must ensure safe disposal by autoclaving and/or incineration of used or unusable preparations of this product. Follow established laboratory procedures in disposing of infectious materials and material that comes into contact with sample must be decontaminated and disposed of in accordance with current laboratory techniques (3,4).

Product Name	Andrade Peptone Water
SKU	M885
Product Type	Regular
Physical Form	Powder
Origin	Animal
Packaging type	HDPE
References	1. MacFaddin J. F., 1985, Media for Isolation-Cultivation-Identification-Maintenance of Medical Bacteria, Vol. I, Williamsand Wilkins, Baltimore.2.Cowan S. T. and Steel K. J., 1974, Manual of Identification of Medical Bacteria, 2nd Ed., Cambridge United Press.3.Finegold S. M. and Baron E. J., 1986, Bailey and Scotts Diagnostic Microbiology, 7th Ed., The C.V. Mosby Co., St. Louis4.Murray P. R., Baron E. J., Jorgensen J. H., Pfaller M. A., Yolken R.H., (Eds.), 8th Ed., 2003, Manual of Clinical Microbiology,ASM, Washington, D.C.
Customized Product Available	No

Andrade Peptone Water

Basal Media Without Carbohydrates#CC293D