Enhancing biofilm resistance and ATP synthesis accelerates toluene degradation at low temperature via AHLs-mediated quorum sensing.

The volatile organic compounds (VOCs) biological purification technology faces the challenge of low performance treating benzene homologues at low temperatures. This study evaluates the strategies that can enhance biofilm low-temperature resistance and microbial adenosine triphosphate (ATP) synthesis rate by adjusting N-acyl homoserine lactone (AHLs) mediated quorum sensing (QS) (adding exogenous AHLs and inoculating AHL-producing bacteria), thereby accelerating toluene degradation at low temperature in biofilters. Experiments demonstrated that AHLs mediated QS can accelerate the proliferation of microorganisms, and maintain a higher proportion of live and psychrotolerant bacteria in biofilm, and significantly accelerate microbial ATP synthesis (44 %-92 %) by increasing nicotinamide adenine dinucleotide (NADH), flavin adenine dinucleotide (FADH₂) concentrations, complex Ⅰ and Ⅱ activity in the respiratory chain, and that resulting in toluene degradation (11 %-13 %) acceleration with the toluene dioxygenase activity and tricarboxylic acid (TCA) cycle promotion at low temperature in biofilters. The findings offer insights into developing effective biofilm-based VOCs purification systems for benzene homologues under challenging low-temperature conditions.