Answer to Question #11764 in Microbiology for Marcy Randall
Negative acid from glucose tests indicate sugar was not metabolized to produce acids. How can growth be accomplished in a carbohydrate test medium when the sugar is not metabolized?
It can mean two possible variants: - a culture don't use sugar and groth only with aminoacids from peptone. - a culture has already utilized sugar and proceeded to peptone nutrition. It follows with a secondary alkalinization in the media.