Selection of quorum quenching (QQ) bacteria for membrane biofouling control: effect of different Gram-staining QQ bacteria, Bacillus sp T5 and Delftia sp T6, on microbial population in membrane bioreactors


Gul B. , İmer D. Y. , Park P., Koyuncu İ.

WATER SCIENCE AND TECHNOLOGY, vol.78, no.2, pp.358-366, 2018 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 78 Issue: 2
  • Publication Date: 2018
  • Doi Number: 10.2166/wst.2018.305
  • Title of Journal : WATER SCIENCE AND TECHNOLOGY
  • Page Numbers: pp.358-366
  • Keywords: Bacillus sp T5, bacterial community, Delftia sp T6, membrane bioreactors, molecular analysis, quorum quenching, COMMUNITY STRUCTURE, WASTE-WATER, IDENTIFICATION, SIGNALS, MBR

Abstract

This study aimed to address the gap in understanding how the microbial community present within quorum quenching-membrane bioreactor (QQ-MBRs) changes during the operations by investigating the behavior of two different types of QQ bacteria, Bacillus sp. T5 and Delftia sp. T6. The antibiofouling effects of T5 and T6 in the QQ-MBR were 85% and 76%, respectively. According to the Illumina HiSeq results, when the QQ-MBR was operated with Gram-positive bacteria, T5, in the mixed liquor a reduction was observed in Gram-positive bacteria and Gram-negative bacteria population increased. In contrast, when the QQ-MBR was operated with Gram-negative bacteria, T6, Gramnegative bacteria population reduced and an increase in Gram-positive bacteria observed. As such, the outputs of the Illumina analysis revealed that use of Gram-negative QQ bacteria in the reactor induced a Gram-positive microbial community and vice versa. This indicates that a close interaction occurs between indigenous Gram-negative and positive bacterial phyla, and Bacillus sp. T5/Delftia sp. T6 is fundamental to the performance of MBRs. This is the first study demonstrating such a relationship and assistance selecting QQ bacteria/strategy in an effective way.