title: [Methodologic problems in the detection of indole formation by anaerobic pathogens].
abstract: The demonstration of indole formation is of great value for the identification of pathogenic anaerobes. A reduction of the pH to values below the critical range of 5.1-5.3 in complex media 5.5 in simple testing substrates, respectively, which is caused by the presence of fermentable carbohydrates and will result in false-negative reactions. For this reason, the indol test should be performed with an adequate buffer capacity and an addition of fermentable carbohydrates should be avoided. Strains showing a false-negative reaction in the spot indole test can be reliably accounted for by means of the rapid test in buffered tryptophan solution described here without having to use additional anaerobic culture methods.
authors.affiliation: Institut für Mikrobiologie, Bereiches Medizin der Martin-Luther-Universität Halle-Wittenberg, Halle/Saale, DDR.
authors.forename: C
authors.initials: C
authors.lastname: Höhne
authors.forename: G
authors.initials: G
authors.lastname: Hübner
authors.forename: D
authors.initials: D
authors.lastname: Sandow
mesh_terms: D001431:Bacteriological Techniques; D001439:Bacteroides / Q000302:isolation & purification* / Q000378:metabolism; D001442:Bacteroides Infections / Q000382:microbiology*; D003470:Culture Media; D005673:Fusobacterium / Q000302:isolation & purification* / Q000378:metabolism; D005674:Fusobacterium Infections / Q000382:microbiology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007211:Indoles / Q000378:metabolism*
chemical_list: D003470:Culture Media; D007211:Indoles; C030374:indole
vernacular_title: Untersuchungen zu methodischen Problemen beim Nachweis der Indolbildung durch anaerobe Krankheitserreger.