Thermo Scientific™ Kligler Iron Agar (Slant)

Description

• Differentiate enteric gram-negative bacilli based on dextrose and lactose fermentation and hydrogen sulfide (H 2 S) production using Thermo Scientific™ Remel™ Kligler Iron Agar (KIA)
• In 1918, Klingler described a medium for detection of H 2 S and differentiation of Salmonella spp
• 1 Edwards and Ewing recommended KIA for determination of H 2 S production by enteric gram-negative bacilli 2
• KIA is also recommended by Gilardi for detection of H 2 S produced by some strains of Pseudomonas 3
• Bailey and Lacey modified the medium by substituting Phenol red indicator for Adrade indicator 4
• Fermentation reactions are read on the slant and in the butt
• Phenol red is an indicator of carbohydrate fermentation whereas, Ferric ammonium citrate is an indicator of H 2 S production
• Ready to use – Solid media Recommended for determination of H 2 S production by enteric gram-negative bacilli 2 and for detection of H 2 S produced by some strains of Pseudomonas 3 Easy to interpret Carbohydrate Fermentation Positive test for Slant/Butt Reaction – Yellow (acid) Negative test for Slant/Butt Reaction – Red (alkaline) KIA Color Reactions Red slat/yellow butt – dextrose (+), lactose (-) Yellow slant/yellow butt – dextrose (+), lactose (+) Red slant/red butt – dextrose (-), lactose (-) Hydrogen Sulphide Production Positive test – Black color throughout medium, a black ring at the juncture of the slant and butt, or a black precipitate in the butt Negative test – No black color development Gas Production Positive test – Bubbles in the medium, cracking and displacement of medium, from side and bottom of tube Negative test – No bubbles and no separation or displacement of the medium This medium contains casein and meat peptones that supply nitrogenous compounds, amino acids and vitamins required for bacterial growth
• Sodium chloride provides essential electrolytes and maintains osmotic equilibrium
• The carbohydrate sources present in the medium are lactose and dextrose
• Phenol red is an indicator of carbohydrate fermentation whereas ferric ammonium citrate is an indicator of H 2 S production.