The methyl red test determines the ability of organism to acidify a phosphate buffered glucose-peptone medium to pH 4.4 or below and culture was inoculated and incubated at room temperature for 48 h. After incubation, two drops of methyl red solution, prepared by dissolving 0.1 g of methyl red in 300 mL ethyl alcohol and 200 mL distilled water, was added to the inoculated medium. A red color indicates positive reaction while yellow color signifies negative reaction.