AUXILIARY DIAGNOSTIC TESTS 3 ml Code No. PT 102
the test of solubility in bile (S. pneumoniae)
Purpose and usage:
Sodium deoxycholate test is determined for a quick and easy differentiation of streptococcus pneumonia from viridans streptococci.
The test utilizes solubility of S. pneumoniae colonies in sodium deoxycholate. Viridans streptococci do not change after sodium deoxycholate treatment.
Technique: The test could be carried out in two modifications:
1. Resuspend the tested strain (1.-2. of McFarland turbidity scale) and drip 3 drops of sodium deoxycholate on it. Incubate for 30 minutes at 37o C.
Note: Suspension of the tested strain in saline without sodium deoxycholate use as the controls.
2. Drip one drop of sodium deoxycholate on the tested grown-up strain on a blood agar and incube for 30 minutes at laboratory temperature.
Result subtracting and evaluation:
1st modification: Clarification occurrs in pneumococci after incubation. Turbidity does not change in viridans streptococci and in the controls.
2nd modification: Dissolution of the colonies in the central zones of viricidation appears within 30 minutes after dripping of sodium deoxycholate on the tested strain. The viridans streptococci remain without any change.
1. Sodium deoxycholate test is available in a package of 3 ml (Code No. PT 102) and is designed for in vitro diagnostics only.
2. Store sodium deoxycholate at + 4o C and let it warm up to laboratory temperature before application.
3. Use it until the expiration date marked on the package.