Aspergillus niger grows faster than Escherichia coli in eosin methylene blue media and deter their growth by reducing the pH of the media

Abstract

Fungi is a kingdom that includes multicellular eukaryotic organisms such as yeast and mold; these organisms are heterotrophs (cannot make their own food) but have significant roles in nutrient cycling. To obtain nutrients from organic material, they use their hyphae, which elongate and branch off swiftly; using the mycelium quickly, they increase their size. Currently, a few media are suitable for fungal growth, such as sabouraud dextrose, malt extract and brain heart infusion medium. Bacterial eosin methylene blue (EMB media) is well-suited to fungi, which acts as selective media to differentiate Gram-negative bacteria. EMB, known as "Levine's formulation”, is a selective and differential medium for Gram-negative bacteria. In EMB media, fungi even grow faster than Gram-negative bacteria. In addition to this faster growth of fungi, it deters the growth of Gram-negative bacteria by reducing the pH. The majority of the time, fungi require specific conditions to flourish. In this study, we observed fungal growth, especially mold (Aspergillus niger), in EMB media and its retardation activity of Gram-negative bacterial growth. For this new finding assurance, we performed the bacterial and fungal identification test further along with repeating the three times of the whole experiment, and we found the same result. The fungal species was A. niger, and the bacterial species was Escherichia coli. [ J Adv Biotechnol Exp Ther 2022; 5(1.000): 229-240]

Keywords

• fungi; emb media; gram-negative bacteria; retardation; growth