High-resolution profiling for the composition of various peptones by multimodal targeting analysis

Peptone is a promising raw material for culturing microorganisms and mammalian cells, but its composition remains unclear. Here, 36 different peptones were comprehensively quantified using five approaches: gas chromatography/tandem mass spectrometry, liquid chromatography/mass spectrometry, ion chromatography, post-column detection-high-performance liquid chromatography, and inductively coupled plasma mass spectrometry (named multimodal targeting analysis). Seventy-eight chemical compounds/ions were detected among 121 targets, including amino acids, nucleic acids, organic acids, sugars, vitamins, and minerals. The sum of the quantitated component weights exceeded 65% of the total weight in all cases (mean 88%). Principal component and cluster dendrogram analyses revealed clear distinctions between not only peptone brands but also production lots. Plant peptones exhibited greater variety than casein and meat peptones. Partial least squares analysis identified components specific to particular manufacturing processes and peptone sources. Acid-digested peptones contained more free amino acids, including Ala, Cys, Gly, Thr, Ser, Asp, Glu, and Pro, than enzyme-digested types.