Lab method
Hippurate hydrolysis test
Purple color = GBS, C. jejuni, Listeria, Gardnerella
HIP-yoor-ate
High-yield clue
A positive (purple) hippurate result separates Group B strep from other beta-hemolytic strep and Campylobacter jejuni from C. coli.
Overview
A biochemical concept detecting hippuricase, which splits hippurate into glycine and benzoic acid; glycine then reacts with ninhydrin to give a purple color.
Classification
- Enzyme-detection concept
- Ninhydrin color readout
- Applied to strep and Campylobacter
Lab & identification clues
- Purple with ninhydrin = hippuricase positive
- Positive: S. agalactiae, C. jejuni, Listeria, Gardnerella
- Separates C. jejuni (+) from C. coli (-)
- Complements CAMP for Group B strep
Associations
- Group B strep confirmation vocabulary
- Campylobacter speciation study clue
- Beta-hemolytic and enteric differentiation
Commonly confused with
- CAMP test
- PYR test
Frequently asked questions
What is Hippurate hydrolysis test?
A biochemical concept detecting hippuricase, which splits hippurate into glycine and benzoic acid; glycine then reacts with ninhydrin to give a purple color.
What is the high-yield clue for Hippurate hydrolysis test?
A positive (purple) hippurate result separates Group B strep from other beta-hemolytic strep and Campylobacter jejuni from C. coli.
What is Hippurate hydrolysis test associated with?
Hippurate hydrolysis test is associated with Group B strep confirmation vocabulary, Campylobacter speciation study clue, and Beta-hemolytic and enteric differentiation.
What is Hippurate hydrolysis test commonly confused with?
Hippurate hydrolysis test is commonly confused with CAMP test and PYR test.
Original concept summary for coursework. Sources checked: OpenStax Microbiology 2e and NCBI Bookshelf Medical Microbiology; reviewed 2026-06. Describes vocabulary and interpretation concepts only; not a lab protocol and not for handling specimens or identifying patient isolates.