<P> This medium is important in medical laboratories by distinguishing pathogenic microbes in a short period of time . </P> <Ul> <Li> Rapid lactose fermentation produces acids, which lower the pH . This encourages dye absorption by the colonies, which are now colored purple - black . </Li> <Li> Lactose non-fermenters may increase the pH by deamination of proteins . This ensures that the dye is not absorbed . The colonies will be colorless . </Li> </Ul> <Li> Rapid lactose fermentation produces acids, which lower the pH . This encourages dye absorption by the colonies, which are now colored purple - black . </Li> <Li> Lactose non-fermenters may increase the pH by deamination of proteins . This ensures that the dye is not absorbed . The colonies will be colorless . </Li>

Eosin and methylene blue dyes in the eosin-methylene blue agar medium