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The chlorophyllin-based photosensitization treatment, being nonthermal, environmentally friendly and cost-effective, has huge potential for microbial control of highly contaminated germinated wheat sprouts and seeds used to produce sprouts.

Pathogenic strains of bacteria are causing various illnesses all around the world and have a major socioeconomic impact. Thus, fast-and low-cost methods for the microbial control of foods are needed. One of them might be photosensitization. This study looks deeper into the mechanism of Escherichia coli damage by chlorophyllin-based photosensitization. Fluorimetric data indicate that after 15 minute incubation with chlorophyllin (Chl) (1.5 × 10 −5 M Chl) 0.73 ± 0.03 μM of this compound was associated with E. coli cell surface. After photoactivation (405 nm, 6-30 J/cm 2) significant reduction (88.2%) of bacterial viability was observed. Higher concentration of Chl (5 × 10 −4 M Chl) reduced viability of bacteria more than by 98%. Results indicated that reactive oxygen species (ROS) took place in this inactivation. Colloidal surface enhanced Raman scattering (SERS) spectroscopy was employed to detect the molecular changes in the treated bacteria. It was found that Chl-based based photosensitization triggers multiple surface structure changes in E. coli what induce lethal unrepairable damages and inactivation of pathogen.