Evaluation and comparison of the microbial consortia enriched by gamma-caprolactone and N-Acyl homoserine lactones for effective quorum sensing disruption

Abstract

This study proposed and compared 3 novel quorum quenching consortia (QQC) composed of abundant quorum quenching (QQ) candidates including bacteria and fungi for effective quorum sensing disruption, which were isolated by mixtures of N-Acyl homoserine lactones (AHLs) and gamma-caprolactone (GCL). AHLs removal analysis indicated that different QQC could efficiently remove specific AHLs. When utilizing AHLs, the growth rates of QQC isolated by the mixtures of AHLs were significantly higher than those utilizing acetate. It congruously suggested that these QQC had higher substrate specificities towards AHLs, indicating their sustainable QQ performance, as compared to that of the QQC enriched by GCL. There was a clear shift in the microbial community diversity and composition among QQC, which were implicated by the structure differences among GCL and AHLs as substrates in the enrichment culture. The different community assemblages within QQC were the main determinants accounting for the diverse QQ performance. Collectively, these findings offered inspiring implications for sustainable QQ bioaugmentation and biostimulation applications in membrane bioreactors (MBRs).