Triple Sugar Iron AgarKligler Iron Agar 1 As mentioned in Th

Triple Sugar Iron Agar/Kligler Iron Agar

1. As mentioned in Theory, the fermentation readings with TSIA and KIA must take place between 18 and 24 hours after inoculation. a.) Why is this true? b.) Is timming as critical with H2S readings? Why or why not?

I WOULD REALLY APPRECIATE SOME HELP WITH THIS QUESTION REGARDING MICROBIOLOGY LAB. THANKS!

Solution

Triple sugar iron agar s used to test the ability of microorganisms in fermenting Sugars and releasing hydrogen sulphide gas. The triple sugar iron Agar test is used to differentiate different genera of enterobacteriaceae Gram Negative bacteria capable of cementing glucose with the production of acid. The production of hydrogen sulphide is identified due to the formation of black precipitate in the back of the yube.

During the first 8 to 12 hours glucose is fermented. The but remains acidik after 18 to 24 hours also because of the presence of organic acids resulted from anaerobic fermentation. When in aerobic conditions releases alkaline amines and C02 and water are released as fermentation products.

The reaction in triple sugar iron Agar cannot be read after 24 hours of incubation because aerobic oxidation of fermentation products formed lactose of sucrose will occur on the slant will regain alkaline state.

Moreover the production of hydrogen sulphide required acidic condition and is indicated by blackening of the butt of the medium in the tube.