Recommended for the microbiological assay of Erythromycin estolate using Klebsiella pneumoniaeATCC 10031 as a test organism in accordance with European Pharmacopoeia, Turbidimetric antibiotic assay is based on the change or inhibition of growth of a test microorganism in a liquid mediumcontaining a uniform concentration of an antibiotic. Use of this method is appropriate only when test samples are clear