Metagenomics revealed the phase-related characteristics during rapid development of halotolerant aerobic granular sludge. (April 2020)

• Record Type: Journal Article
• Authors: Li, Wei; Yao, Jin-chi; Zhuang, Jin-long; Zhou, Yuan-yuan; Shapleigh, James P.; Liu, Yong-di
• Is Part Of: Environment international. Volume 137(2020)
• Publication Date: 2020-04
• Subjects: Salt-tolerant AGS -- Rapid granulation -- Metagenomics -- Fungi; Environmental protection -- Periodicals; Environmental health -- Periodicals; Environmental monitoring -- Periodicals; Environmental Monitoring -- Periodicals; Environnement -- Protection -- Périodiques; Hygiène du milieu -- Périodiques; Environnement -- Surveillance -- Périodiques; Environmental health; Environmental monitoring; Environmental protection; Periodicals; 333.705
• DOI: 10.1016/j.envint.2020.105548
• Languages: English
• ISSNs: 0160-4120

Abstract

Graphical abstract: Highlights: Development of rapid growth of salt-tolerant AGS from activated sludge. Three distinct developmental phases during granule maturation were observed. Initial phase dominated by EPS producing bacteria Mangrovibacter . Bacterial-fungal interaction supported the maintenance of mature salt-tolerant AGS. Abstract: Efforts to produce aerobic granular sludge (AGS) for high-efficient and stable nutrient removal in high saline wastewaters have gained much attention recently. This study was undertaken to describe the phase-related characteristics of the rapid formation of glucose-fed salt-tolerant AGS (SAGS) generated from common municipal activated sludge using metagenomic approaches. The time needed for SAGS formation is about 11 days in a multi-ion matrix salinity of 3%. There were three distinct developmental phases during sludge maturation which were designated: I) the salinity adaptation phase (days 1–2), II) the particle-size transition phase (days 3–5) and III) the maturation and steady-state phase (days 6–11), respectively. Genome-based analysis revealed that during the phase I, members of the genus Mangrovibacter, which has the potential to secrete extracellular polymeric substances (EPS), dominated during the formation of initial SAGS aggregates. During phase II, fungi of the class Saccharomycetes, in particular the genus Geotrichum, became dominant and provided a matrix for bacterial attachment. This mutualistic interaction supported the rapid development and maintenance of mature SAGS. This work characterizes a robust approach for the rapid development of SAGS for efficient saline sewage treatment and provides unique insight into the granulation mechanism occurring during the development process.