Diagnostic device > Diagnostic discs
DIAGNOSTIC DISCS 100 discs Code: DD 515
ITEST NOVOBIOCIN
for the differentiation of coagulase negative Staphylococci
Purpose and usage:
NOVOBIOCIN diagnostic discs are designed for an easy differentiation of plasmacoagulase negative Staphylococci.
Principle:
The test is based on the resistance of some species of plasmacoagulase negative Staphylococci to novobiocin.
Technique:
Inoculate evenly Mueller-Hinton agar plate with the examined strain (it is better to prepare a flood plate by inoculating 3 hr. broth culture with a turbidity of 0.5 according to McFarland scale). Put NOVOBIOCIN disc by aseptic technique on the plate and incubate for 24 hours at 37°C.
Evaluation:
Measure the diameter of the inhibition zone after incubation:
Inhibition zone (mm) Staphylococci to novobiocin
< 15 Resistant
> 15 Susceptible
Resistant species of coagulase negative staphylococci:
Human medicine: Staphylococcus xylosus, S. saprophyticus, S. cohnii subs. cohnii, S. cohnii subs. urealyticum and rarely occuring species S. sciuri and S. lentus.
Veterinary medicine: S. gallinarum, S. arlettae, S. equorum and S. kloosii.
Other species of coagulase negative staphylococci described till now are susceptible to novobiocin.,
Warning:
1. NOVOBICIN discs are designed for laboratory use only.
2. Discs should be stored in a dark place at +4°C and should not be used beyond the expiration date shown on the packing.
