Definition of peptone in English:



  • 1[mass noun] A soluble protein formed in the early stage of protein breakdown during digestion.

    • ‘Supplementation of cultures with the rich nutrient peptone has been previously shown to suppress submerged culture conidiation.’
    • ‘They are professional colleagues, too, and have published a paper together about immunity from the anticoagulant action of peptone.’
    • ‘Yeast extract / peptone / dextrose, synthetic selective media, and minimal media were prepared as described.’
    1. 1.1A solution of peptone in saline, used as a liquid medium for growing bacteria.
      • ‘Bactosoytone, the medium that is used to cultivate bacteria in the process of making monosodium glutamate, is one of the peptones.’
      • ‘Standard yeast media and cultivation were employed and yeast were grown on yeast extract / peptone / dextrose media at 30° unless indicated otherwise.’
      • ‘Briefly, S. Typhimurium was grown on nutrient agar and passed into peptone water before subculturing on Congo red agar.’
      • ‘I will need some lactose broth and the modified peptone water so I can test for all possibilities.’
      • ‘Yeast strains were grown in yeast extract / peptone / dextrose with 2% glucose or in synthetic defined minimal media supplemented with appropriate amino acids and 2% glucose.’


Mid 19th century: from German Pepton, from Greek pepton, neuter of peptos cooked, digested.