KLIGLER IRON AGAR 1/5

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1 KLIGLER IRON AGAR INTENDED USE Kligler Iron Agar is used for the identification of enterobacteria by the rapid detection of lactose and glucose fermentation (with or without gas production), as well as the production of hydrogen sulfide. HISTORY In 1911, Russell described a medium containing two sugars for the isolation of typhoid bacilli in urine. Six years later, Kligler developed a nutrient medium with glucose, Andrade's indicator and lead acetate for the differentiation of bacilli from the typhi and paratyphi groups. While experimenting this medium with other combinations of ingients, Kligler found that Russell's medium containing Andrade's indicator and lead acetate led to an excellent differentiation of salmonellae. Bailey and Lacey subsequently recommended using phenol as ph indicator, replacing Andrade's indicator which was less adapted to this type of reaction. Sulkin and Willett used sodium thiosulfate and ferrous sulfate to demonstrate hydrogen sulfide production. PRINCIPLES The fermentations of lactose and glucose, used to differentiate species of enterobacteria, result in acidification which makes phenol (ph indicator) turn. Microorganisms not fermenting lactose (Salmonella or Shigella) initially product a slant due to the acidification resulting from glucose present in small quantities. When the glucose has been exhausted in the aerobic portion of the slant, the reaction becomes basic by oxidation of the acids produced, resulting in the phenomenon of a color on the surface of the medium. This color does not appear in depth in the butt, where the color remains. Bacteria fermenting lactose and glucose make the slant and the butt turn because of the production of large quantities of acid. This is sufficient to maintain an acid ph on the surface. Microorganisms which ferment neither of these two sugars do not change the color of the medium. The production of H 2 S is revealed in the base of the medium by the appearance of black iron sulfide, due to the uction of thiosulfate in the presence of ferric citrate. The production of gas (H 2, CO 2 ) resulting from sugar fermentations is shown by the appearance of gas bubbles or by a fragmentation of the agar. PREPARATION Suspend 58.0 g of dehydrated medium (BK034) in 1 liter of distilled or deionized water. Slowly bring to boiling, stirring with constant agitation until complete dissolution. Dispense in tubes. Sterilize in an autoclave at 121 C for 15 minutes. Incline the tubes so as to obtain a butt 3 cm in height and an oblique slant. 1/5 Tél : 33 (0) Fax : 33 (0)

2 NOTE 1 : Incomplete agar melting during preparation will invariably lead to significant inconsistency in the gel strength of the solidified agar, after sterilization and cooling. NOTE 2 : If the medium is not used within one week of its preparation, it is recommended to regenerate it in a boiling water bath and to resolidify it in a slanted position. INSTRUCTIONS FOR USE Using a suspected colony taken from a selective isolation medium, inoculate the butt by stabbing in the center and the inclined surface by closely spaced streaks. Pure cultures taken from the center of well isolated colonies must be used to avoid cross reactions which will make identification impossible. Incubate at 37 C for 24 hours with caps loosely screwed to favor gas exchanges. RESULTS Kligler's medium supplies four types of information: (1) Glucose fermentation Red butt : glucose not fermented Yellow butt : glucose fermented (2) Lactose fermentation Red slant : lactose not fermented Yellow slant : lactose fermented (3) Gas production Production of gas bubbles in the butt of the tube. (4) Formation of H 2 S Formation of a black color between the butt and the slant or along the inoculation stab. 2/5 Tél : 33 (0) Fax : 33 (0)

3 Typical reactions are listed in the following table : SPECIES Salmonella Typhi (2) Salmonella Paratyphi A (2) Salmonella Choleraesuis (2) Salmonella Pullorum (2) Salmonella Paratyphi B (2) Salmonella Typhimurium (2) Salmonella Enteritidis (2) Salmonella Gallinarum (2) Shigella dysenteriae Shigella flexneri Shigella sonnei Shigella boydii Proteus vulgaris Proteus mirabilis Proteus morganii Proteus rettgeri SLANT BUTT Lactose Glucose Gas Serratia marcescens Enterobacter hafniae Enterobacter aerogenes Enterobacter cloacae Escherichia coli (1) Citrobacter freundii Klebsiella pneumoniae Alcaligenes faecalis Pseudomonas aeruginosa Yersinia enterocolitica (1) (2) Some strains of Escherichia coli ferment lactose only very late in growth. In the case where interpretation may suggest the presence of salmonellae, it is possible to use Kligler cultures to detect βgalactosidase, urease and lysinedecarboxylase. [] H 2 S TYPICAL COMPOSITION (can be adjusted to obtain optimal performance) For 1 liter of medium : Tryptone g Yeast extract g Meat extract g Glucose g Lactose g Sodium chloride g Sodium thiosulfate g Ferric ammonium citrate g Phenol mg Bacteriological agar g ph of the readytouse medium at 25 C : 7.4 ± /5 Tél : 33 (0) Fax : 33 (0)

4 QUALITY CONTROL Dehydrated medium : pinkish powder, freeflowing and homogeneous. Prepa medium : orange agar. Typical culture response after 1824 hours of incubation at 37 C : Microorganisms Growth Slant Butt H 2 S Gas Escherichia coli ATCC Escherichia coli RIVM WR1 Citrobacter freundii CIP 57.32T Proteus vulgaris ATCC Salmonella Enteritidis CIP Pseudomonas aeruginosa CIP [] STORAGE / SHELF LIFE Dehydrated medium : 230 C. The expiration date is indicated on the label. Prepa medium (benchmark value*) : Media in tubes nonslanted : 6 months at 28 C. Media in slants : 8 days at 28 C. PACKAGING Code Dehydrated medium : 500 g bottle BK034HA 4/5 Tél : 33 (0) Fax : 33 (0)

5 BIBLIOGRAPHY RUSSELL, F.F The isolation of typhoid bacilli from urine and feces with the description of a new double sugar tube medium. J. Med. Red. Res., 25 : KLIGLER, I.J A simple medium for the differentiation of the members of the typhoidparatyphoid group. American Journal of Public Health, 7 : KLIGLER, I.J Modifications of culture media used in the isolation and differentiation of typhoid, dysentery, and allied bacilli. Journal of Experimental Medicine, 28 : BUTTIAUX, R L Analyse bactériologique des eaux de consommation. Editions médicales Flammarion, Paris. BUTTIAUX, R., BEERENS, H., et TACQUET, A Manuel de techniques bactériologiques. Editions médicales Flammarion, Paris. NF EN ISO (V 08027). Décembre Microbiologie des aliments. Méthode horizontale pour la recherche de Yersinia enterocolitica présumées pathogènes. XP CEN ISO/TS (V ). Janvier Microbiologie des aliments. Guide pour la préparation et la production des milieux de culture. Partie 2 : Guide général pour les essais de performance des milieux de culture. XP X Février Caractérisation des boues. Dénombrement des Salmonella. Méthode de dénombrement en milieu liquide (méthode du nombre le plus probable NPP). NF V Mars Microbiologie des aliments. Dénombrement des Pseudomonas spp. dans les viandes et produits à base de viande et les volailles. Methode de routine. NF U Juillet Méthodes d analyse en santé animale. Recherche par l isolement et identification de tout sérovar ou de sérovar(s) spécifié(s) de salmonelles dans l environnement des productions animales. NF U Novembre Méthodes d analyse en santé animale. Isolement et identification de tout sérovar ou de sérovar(s) spécifié(s) de salmonelles chez les oiseaux. NF U Janvier Méthodes d analyse en santé animale. Isolement et identification de tout sérovar ou de sérovar(s) spécifié(s) de salmonelles chez les mammifères. *Benchmark value refers to the expected shelf life when prepa under standard laboratory conditions following manufacturer s instructions. It is provided as a guide only and no warranty, implied or otherwise is associated with this information. The information provided on the package take precedence over the formulations or instructions described in this document. The information and specifications contained in this technical data sheet date from They are susceptible to modification at any time, without warning. Code document : BK034/A/ : 7. 5/5 Tél : 33 (0) Fax : 33 (0)