Kinetic and microbial response of activated sludge community to acute and chronic exposure to tetracycline

Pala Özkök İ., Ubay-Cokgor E., Jonas D., Orhon D.

JOURNAL OF HAZARDOUS MATERIALS, vol.367, pp.418-426, 2019 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 367
  • Publication Date: 2019
  • Doi Number: 10.1016/j.jhazmat.2018.12.094
  • Journal Name: JOURNAL OF HAZARDOUS MATERIALS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.418-426
  • Keywords: Aerobic processes, Tetracycline, Chronic inhibition, Activated sludge modeling, High-throughput sequencing, WASTE-WATER, GENE CASSETTES, ANTIBIOTICS, BIODEGRADATION, REPRESSOR, ERYTHROMYCIN, COMPLEX, GROWTH
  • Istanbul Technical University Affiliated: Yes

Abstract

Current study aimed to discover both kinetic and microbial response of activated sludge biomass to continuous exposure to tetracycline, one of the most frequently detected antibiotics in wastewaters. Respirometric analysis and model evaluation of the oxygen utilization rate profiles generated at critical phases of the experimental period showed that, continuous exposure to tetracycline caused complete suppression of substrate storage aside from mild inhibition on the growth kinetics and it exerted a significant binding action with available organic carbon, leading to less oxygen consumption. Additionally, increase in endogenous decay rates by 1.5 fold was associated with maintenance energy dictated by the presence and production of antibiotic resistance genes, as demonstrated by resistance gene profile. High-throughput sequencing results showed that continuously exposure to tetracycline caused a significant shift in the community structure at species level so that tetracycline resistant bacteria like Arthrobacter sp and Diaphorobacter sp dominated the bacterial community.