Identification of a predominant effect on bacterial cell disruption and released organic matters by a high-pressure jet device

• E. coli and B. subtilis cells were disrupted by a high-pressure jet device (HPJD).
• Cell disruption by HPJD most significantly depended on the applied pressure.
• Tryptophan and tyrosine-like compounds were dominantly released from bacteria.
• HPJD increased aromaticity of dissolved organic matter lysed from bacterial cells.

This study characterizes the performance of a high-pressure jet device (HPJD) that destroys bacterial cells and releases dissolved organic matter (DOM). Specifically, it investigates the effects of pressure, repeated batch treatment, and injection ratio on the disintegration of Escherichia coli and Bacillus subtilis cells. HPJD treatment was more effective at an injection ratio of 3 than of 1. The amounts of DNA, protein and polysaccharide released from disrupted cells increased with increasing pressure and number of HPJD treatments. In the kinetic analysis, bacterial cell disintegration chiefly depended on the pressure applied in the HPJD. Fluorescence three-dimensional excitation–emission matrix (3DEEM) spectra revealed that tryptophan- and tyrosine-like substances were released from E. coli and B. subtilis cells after HPJD treatment. This was corroborated by the UV–vis spectra, which revealed concomitant increases in aromaticity and decreased molecular weight of the DOMs expelled from both species.