Tsi media & it's interpretation

This article will definitely make you understand about TSI media & it's result.

1. TSI MEDIA
Kaushik Sen
MLT,Dept of Microbiology, ESIC
MED. COLLEGE

2. •TheTriple Sugar Iron(TSI) test is
amicrobiologicaltest roughly named
for its ability to test a microorganism's
ability to ferment sugars and to
producehydrogen sulfide.
[1]
It is often
used todifferentiateenteric bacteria
includingSalmonellaandShigella.

3. Uninoculated
TSI Media

6. Straight wire

7. Uninoculated
TSI Media

8. HOW TO INOCULATE TSI
MEDIA?

9. •With a straight inoculation needle, touch
the top of a well-isolated colony.
•Inoculate TSI by first stabbing through
the center of the medium to the bottom
of the tube and then streaking the surface
of the agar slant.
•Leave the cap on loosely and incubate the
tube at 35°-37°C in ambient air for 18 to
24 hours.
•Examine the reaction of medium.

10. Result after overnight incubation at 37

11. SLANT/BUTT
A/A+ GAS(CO2)
•Glucose, Lactose
& / or sucrose is
fermented
•Bubbles or cracks
present -gas
production
K–Alkaline
A--Acidic

12. SLANT/BUTT
K/A (no gas)
•Only
Glucose is
fermented
K–Alkaline
A--Acidic

13. SLANT/BUTT
K/K (no gas)
•No sugar is
fermented
K–Alkaline
A--Acidic

14. SLANT/BUTT
K/A+ GAS(H2S)
•Only Glucose is
fermented
•Black precipitate
present -H2S gas
production
K–Alkaline
A--Acidic

15. SLANT/BUTT
A/A+ GAS(CO2+H2S)
•Glucose, Lactose &/
or Sucrose are
fermented
•Butt region turns
Black due to
Hydrogen sulphide
K–Alkaline
A--Acidic

18. TSI RESULT FOR DIFFERENT
BACTERIA

19. Y = yellow = Acid R=red= Alkaline

20. TSI agar slant results: (from left) preinoculated (as control),P. aeruginosa,E.
coli,Salmonella Typhimurium,Shigella flexneri

21. TSI RESULT

23. END