Understanding the N-acylated homoserine lactones(AHLs)-based quorum sensing for the stability of aerobic granular sludge in the aspect of substrate hydrolysis enhancement
Document Type
Article
Publication Date
2-1-2023
Abstract
Efficient substrate metabolism is the premise for stable operation of aerobic granular sludge and can be regulated by quorum sensing (QS). In this study, starch and acetate were selected to represent complex and simple substrates to provide comparable amount of metabolic energy for granules cultivation. Starch-fed granules were larger in size and contained higher EPS content than acetate-fed granules, though both granules exhibited similar substrate-degradation rates during sequencing batch reactor (SBR) cycle. Three N-acylhomoserine lactones (AHLs), including C8-HSL, 3OHC8-HSL and 3OHC12-HSL, were detected as dominant autoinducers in granules. They accumulated more in starch-fed granules than acetate-fed granules. The batch experiments were implemented to investigate QS regulation for granular stability in terms of substrate hydrolysis and transformation. The addition of three AHLs increased the activity of α-amylase, the main starch hydrolase, 4–6 times, significantly (p < 0.01) higher than the control treatment without AHLs amendment. While activity of dehydrogenase, the main simple substrate degradation enzyme, was increased only 1–2 times. Higher enzyme activity, especially α-amylase, significantly (p < 0.05) promoted the substrate-degradation rate (65 % than control group) and EPS yield in starch-fed system. Overall, QS can facilitate complex substrate uptake via hydrolysis enhancement and EPS secretion, which together promote sludge granulation and stability.
Identifier
85141802013 (Scopus)
Publication Title
Science of the Total Environment
External Full Text Location
https://doi.org/10.1016/j.scitotenv.2022.159581
e-ISSN
18791026
ISSN
00489697
PubMed ID
36397605
Volume
858
Grant
52070164
Fund Ref
National Natural Science Foundation of China
Recommended Citation
Zhang, Zhiming; Wang, Linlin; Ji, Yatong; Cao, Runjuan; Zhou, Jiaheng; Li, Mengyan; Zhu, Liang; and Xu, Xiangyang, "Understanding the N-acylated homoserine lactones(AHLs)-based quorum sensing for the stability of aerobic granular sludge in the aspect of substrate hydrolysis enhancement" (2023). Faculty Publications. 1970.
https://digitalcommons.njit.edu/fac_pubs/1970
