Microbiology

Selenite Cystine Broth

It is recommended as a selective enrichment media for Salmonella and possibly Shigella sonnei from faeces, urine, water and foodstuffs.

Range	Microbiology
Composition	Formula per liter of medium: Tryptone 5.000 gm.; Lactose 4.000 gm.; Disodium phosphate 10.00 gm.; L-Cystine 0.010 gm.; Final pH 7.0 ± 0.2 at 25°C
Preparation	Suspend 19.01 grams in 1000 ml purified / distilled water. Add 4 grams of sodium hydrogen selenite. Adjust pH to 7.0 ± 0.2 at 25°C. Warm to dissolve the medium completely. Distribute in sterile test tubes. Sterilize in a boiling water bath or free flowing steam for 10 minutes. DO NOT AUTOCLAVE. Excessive heating is detrimental. Discard the prepared medium if large amount of selenite is reduced (indicated by red precipitate at the bottom of tube/bottle).
Storage	BioScien Selenite Cysteine broth dehydrated media are stable until expiration date stated on label when properly stored 10-30°C. The prepared medium should be stored at 2-8°C. Use before expiry date on the label. On opening, product should be properly stored dry, after tightly capping the bottle in order to avoid lump development due to the hygroscopic nature of the product. Improper storage of the product may lead to lump formation. Store in a 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.
Appearance	The color of BioScien Selenite Cystine broth is Cream to light yellow homogeneous free flowing powder. If there are any physical changes, discard the medium. The hydrated medium is Cream to yellow coloured clear solution without any precipitate, media should not be used if there are any signs of deterioration (shrinking, cracking, or discoloration), and contaminations.
Specimen	Clinical samples: faeces, urine
Pack sizes	3 options