Antibiofilm and Antiquorum Sensing Potential of <i>Pheretima posthum</i>

Antibiotic resistance is a world wide problem mainly in developing countries. In this work, coelomic fluid (PCF) and paste (PBP) of Pheretima posthuma was assessed for its potential as antibiofilm and anti-quorum sensing (QS) agent against pathogenic bacterial biofilms. PCF and PBP were extracted and biofilm formation time kinetics was examined using crystal violet staining method by utilizing four bacterial isolates in bispecies biofilm (06 combinations; MH5-MH10) and multi species biofilms (05 combinations; MH11-MH15). QS study was performed by determining pyocyanin formation time kinetics using 03 P. aeruginosa strains at various time periods (0, 24, 48, 72, 96 and 120 hours). Following next, anti- QS effect was analyzed by measuring pyocyanin concentrations. Results showed that among bispecies bacterial biofilms, MH5-MH7 combinations showed significantly higher biofilm (p < 0.05) after 72 hours while other three (MH8-MH10) produced maximum biofilm after 48 to 72 hours. Likewise, for multispecies biofilms, maximum biofilm was noted after 48-72 hours. QS analysis revealed that PA1 strain synthesized highly significant (p < 0.001) pyocyanin (20 µg/mL) after 96 hours compared to PA2 and PA3 strains, which formed significant pyocyanin (18 µg/mL) after 72 hours. Also, 100-150 µg/mL of both PCF and PBP exhibited a significant (p < 0.05) reduction in biofilm while 200 µg/mL concentration showed highest QS against all selected strains. To our knowledge, this is the first assessment of its kind on the potential application of earthworm PCF and PBP for its antibiofilm and anti-QS potential. The study recommends precise chemistry of bioactive agents and their probable mechanism(s) of actions for the observed interference. Also, new pharmaceutical drugs synthesized using bioactive agents from PCF and PCB may surely have the potential to manage different infection problems caused by bacterial biofilms.