title: Investigation of intertidal wetland sediment as a novel inoculation source for anaerobic saline wastewater treatment.
abstract: Biological treatment of saline wastewater is considered unfavorable due to salinity inhibition on microbial activity. In this study, intertidal wetland sediment (IWS) collected from a high saline environment was investigated as a novel inoculation source for anaerobic treatment of saline pharmaceutical wastewater. Two parallel lab-scale anaerobic sequencing batch reactors (AnSBR) were set up to compare the organic removal potential of IWS with conventional anaerobic digested sludge (ADS). Under steady-state condition, IWS reactor (R(i)) showed organic reduction performance significantly superior to that of ADS reactor (R(a)), achieving COD removal efficiency of 71.4 ± 3.7 and 32.3 ± 6.1%, respectively. In addition, as revealed by fluorescent in situ hybridization (FISH) analysis, a higher relative abundance of methanogenic populations was detected in R(i). A further 16S rRNA gene pyrosequencing test was conducted to understand both the bacterial and archaeal community populations in the two AnSBRs. A predominance of halophilic/tolerant microorganisms (class Clostridia of bacteria, genera Methanosarcina, and Methanohalophilus of archaea) in R(i) enhanced its organic removal efficiency. Moreover, several microbial groups related with degradation of hardly biodegradable compounds (PAHs, n-alkenes, aliphatic hydrocarbons, and alkanes, etc.) were detected in the IWS. All these findings indicated that IWS is a promising inoculation source for anaerobic treatment of saline wastewater.
authors.affiliation: †Centre for Water Research, Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576.
authors.forename: Xueqing
authors.initials: X
authors.lastname: Shi
authors.affiliation: †Centre for Water Research, Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576.
authors.forename: Kok Kwang
authors.initials: KK
authors.lastname: Ng
authors.affiliation: ‡Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China.
authors.forename: Xiao-Ran
authors.initials: XR
authors.lastname: Li
authors.affiliation: †Centre for Water Research, Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576.
authors.forename: How Yong
authors.initials: HY
authors.lastname: Ng
mesh_terms: D000693:Anaerobiosis; D001105:Archaea / Q000235:genetics / Q000378:metabolism; D001419:Bacteria / Q000235:genetics / Q000378:metabolism; D018533:Biomass; D019015:Geologic Sediments / Q000382:microbiology*; D017404:In Situ Hybridization, Fluorescence; D008697:Methane / Q000378:metabolism; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D054712:Salinity; D017422:Sequence Analysis, DNA; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000382:microbiology*; D014872:Water Movements; D018508:Water Purification / Q000379:methods*; D053833:Wetlands
chemical_list: D008697:Methane; D012336:RNA, Ribosomal, 16S; D062065:Wastewater