Insights into the microalgae-bacteria consortia treating swine wastewater: Symbiotic mechanism and resistance genes analysis

• Published in: Bioresource technology Vol. 349; p. 126892
• Main Authors: Li, Shengnan, Chu, Yuhao, Xie, Peng, Xie, Youping, Chang, Haixing, Ho, Shih-Hsin
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.04.2022
• Subjects: Animals; Anti-Bacterial Agents - pharmacology; Antibiotic resistance genes (ARGs); Bacteria - genetics; Chlorella; Extracellular Polymeric Substance Matrix; Genes, Bacterial - genetics; Low C/N ratio; Microalgae - genetics; Microalgae-bacteria consortia (MBC); Microbial community; Sulfamethoxazole (SMX); Swine; Waste Water; Microalgae-bacteria consortia (MBC); Sulfamethoxazole (SMX); Antibiotic resistance genes (ARGs); Low C/N ratio; Microbial community
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2022.126892

[Display omitted] •Symbiotic microalgae-activated sludge enhanced the NH4+-N removal.•Hydroxylation, bond cleavage, deamination were the main SMX degradation mechanisms.•The absolute abundance of ARGs is relatively less in microalgae-bacteria consortia.•The bacterial community structure was affected by introducing microalgae.•Proteobacteria and Ascomycota have a synergistic effect on C. pyrenoidosa. This study investigated the effects of microalgae-bacteria consortia (MBC) (Chlorella pyrenoidosa-activated sludge (AS)) treating swine wastewater with low C/N ratios. After co-culture, the removal rates of NH4+-N and PO43--P increased by 53.84% and 43.52%. Furthermore, the sulfamethoxazole (SMX) degradation rates in MBC were slightly higher than in the activated sludge process. Interestingly, the absolute abundance of antibiotic resistance genes (ARGs) in effluent from MBC is relatively less than in the AS process. C. pyrenoidosa has a negative zeta potential that allows bacteria to adhere to its surface. The concentrations of carbohydrates and proteins in extracellular polymeric substance (EPS) of MBC dramatically increased compared with the AS process. At the phylum level, Proteobacteria, Bacteroidota, and Cyanobacteria were the main bacteria, while Ascomycota and Basidiomycota were the primary fungi in MBC. Overall, those findings lead to a better understanding of the swine wastewater containing antibiotic treatment by MBC.