Used for microbiological assay of pantothenic acid or its salts using Lactobacillus plantarum ATCC 8014 as the test organism. Since the pantothenate is required for the growth of Lactobacillus plantarum assay strain, growth of the organism will occur only if the materials being assayed contain pantothenate. Exact concentration of pantothenate in the test material can be calculated by comparing results with standard curve of pantothenate.