TCBS Agar-HI Media

About TCBS Agar-HI Media

Product Description

Thiosulfate-Citrate-Bile Salts-Sucrose (TCBS) Agar is a specialized medium used in microbiology laboratories for the selective isolation and cultivation of Vibrio species, particularly Vibrio cholerae and Vibrio parahaemolyticus. Let's dive into the details:

1. Composition of TCBS Agar:

   • Sucrose: 20.0 g
   • Dipeptone: 10.0 g
   • Sodium Citrate: 10.0 g
   • Sodium Thiosulfate: 10.0 g
   • Sodium Chloride: 10.0 g
   • Yeast Extract: 5.0 g
   • Oxbile (Oxgall): 5.0 g
   • Sodium Cholate: 3.0 g
   • Ferric Citrate: 1.0 g
   • Bromothymol Blue: 0.04 g
   • Thymol Blue: 0.04 g
   • Agar: 15.0 g
   • Final pH: 8.6 ± 0.2 at 25C1.

2. Principle of TCBS Agar:

   • TCBS Agar selectively inhibits the growth of Enterobacteria and Vibrio species.
   • Thiosulfate, sodium citrate, and the alkaline environment suppress Enterobacteria.
   • Ox bile and sodium cholate slow down enterococci growth and inhibit Gram-positive bacteria.
   • Vibrio species ferment sucrose, leading to acidification and turning bromothymol blue yellow.
   • Thiosulfate serves as a sulfur source, allowing visualization of hydrogen sulfide production in the presence of ferric citrate.
   • Yeast extract and peptone provide essential nutrients for Vibrio growth.