Aim: Biofilm is the major causative factor of infectious diseases. Difficulty in combating biofilm-related diseases is typically due to persisters, heterogeneous microbial population and viscoelastic extracellular polymeric substances (EPS) matrix. Antibiofilm activities of Chromolaena odorata extracts have previously been demonstrated, however, the effects of its treatment on the biofilm proteome expression remains not well understood. Thus, this study was carried out to profile changes in biofilm proteome of Pseudomonas aeruginosa following treatment with chloroform and ethanol extracts of C. odorata.

Methodology and results: Biofilm was developed in 6-well microplate in the presence or absence of C. odorata extracts overnight at 37 °C. Whole-cell proteome analysis was carried out by combining two-dimensional polyacrylamide gel electrophoresis and mass spectrometry. Treatment with C. odorata extracts triggered changes in two-dimensional proteome profiles of P. aeruginosa biofilm under aerobic and anaerobic conditions. The differentially expressed proteins were successfully identified and were assigned to various functional categories including protein metabolism, carbohydrate metabolism, peptidoglycan metabolism, electron transport and iron transport.

Conclusion, significance and impact of study: The present study demonstrates differential proteome expression in P. aeruginosa biofilm following treatment with C. odorata extracts. This suggests that C. odorata extracts may target multiple biological processes to control P. aeruginosa biofilm. C. odorata extracts may be useful for development of novel antibiofilm agents.