It's not that the test detects the glucose. It is the absence of starch that is why we see a change in the agar. Without starch intact the media will not be black and that is why we see clearing around the growth,
Hi, I am doing an unknown for micro at my school, and my bacteria is bacillus cereus according to my lecithinase results. When I did the amylase test on this bacteria, it was negative even though it should positive. Any idea why? I did a catalase test to differentiate between clostridium sporogenes and bacillus cereus...I don’t know what could’ve happened. Thank you!
I know this was asked a year ago, but my thought is that maybe your Bacillus cereus was dead. That happened in my class this quarter. The entire bacteria colony had died.
Thanks Dr. Wells! You explained everything so well.
Kindly make a video on cellulase as well
Great vid!
Which book?
Why glucose medium repress the starch hydrolysis?
It's not that the test detects the glucose. It is the absence of starch that is why we see a change in the agar. Without starch intact the media will not be black and that is why we see clearing around the growth,
Hi, I am doing an unknown for micro at my school, and my bacteria is bacillus cereus according to my lecithinase results. When I did the amylase test on this bacteria, it was negative even though it should positive. Any idea why? I did a catalase test to differentiate between clostridium sporogenes and bacillus cereus...I don’t know what could’ve happened. Thank you!
I know this was asked a year ago, but my thought is that maybe your Bacillus cereus was dead. That happened in my class this quarter. The entire bacteria colony had died.
What media is used ?
This experiment uses starch agar plates.