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Substantial evidence suggests that all types of water, such as drinking water, wastewater, surface water, and groundwater, can be potential sources of Helicobacter pylori (H. pylori) infection. Thus, it is critical to thoroughly investigate all possible preconditioning methods to enhance the recovery of H. pylori, improve the reproducibility of subsequent detection, and optimize the suitability for various water types and different detection purposes. In this study, we proposed and evaluated five distinct preconditioning methods for treating water samples collected from multiple urban water environments, aiming to maximize the quantitative qPCR readouts and achieve effective selective cultivation. According to the experimental results, when using the qPCR technique to examine WWTP influent, effluent, septic tank, and wetland water samples, the significance of having a preliminary cleaning step becomes more evident as it can profoundly influence qPCR detection results. In contrast, the simple, straightforward membrane filtration method could perform best when isolating and culturing H. pylori from all water samples. Upon examining the cultivation and qPCR results obtained from groundwater samples, the presence of infectious H. pylori (potentially other pathogens) in aquifers must represent a pressing environmental emergency demanding immediate attention. Furthermore, we believe groundwater can be used as a medium to reflect the H. pylori prevalence in a highly populated community due to its straightforward analytical matrix, consistent detection performance, and minimal interferences from human activities, temperature, precipitation, and other environmental fluctuations.

Urban rivers were often cut off during engineering construction in regions with dense river network, causing severe deterioration of the river eco-system. Due to little research conducted on the blocked river remediation, this study applied integrated engineering measures including aeration, planted floating beds, fiber biofilm carriers, and microbial reagents to remediate a blocked river in-situ. The concentrations of NH3 -N, total phosphorus (TP), and CODMn of the blocked river were markedly reduced, with removal efficiencies of 50.5-94.7%, 15.8-78.2%, and 30.4-78.7% after 3-months remediation, respectively. Negative correlations were found between NH3 -N and temperature, pH, between TP and pH, probably due to season and/or pH dependent biological processes. Positive correlation between CODMn and dissolved oxygen suggests the efficiency of artificial aeration in COD elimination. The biofilms developed on fibers showed temporal and spatial variations in quantity and extracellular polymeric substances (EPS) composition. The biofilm EPS was dominated by humic acid-like compounds with low freshness, while the dissolved organic matter in the river mainly consisted of aromatic proteins and fulvic acid-like compounds with high freshness which may attributed to the microbial reagents. No secondary pollution from sediment was observed. Results suggest integrated ecological remediation as a feasible strategy for the blocked river remediation. [ABSTRACT FROM AUTHOR]