Nucleic acid amplification of biomarkers is increasingly used to monitor microbial activity and assess remedial performance in contaminated aquifers. Previous studies described the use of filtration, elution, and direct isothermal amplification (i.e. no DNA extraction and purification) as a field-able means to quantify Dehalococcoides spp. in groundwater. This study expands previous work with direct loop mediated isothermal amplification (LAMP) for the detection and quantification of Dehalobacter spp. in groundwater. Experiments tested amplification of DNA with and without crude lysis and varying concentrations of humic acid. Three separate field-able methods of biomass concentration with eight aquifer samples were also tested, comparing direct LAMP with traditional DNA extraction and quantitative PCR (qPCR). A new technique was developed where filters were amplified directly within disposable Gene-Z chips. The direct filter amplification (DFA) method eliminated an elution step and provided a detection limit of 102
Dehalobacter cells per 100 mL. LAMP with crudely lysed Dehalobacter had a negligible effect on threshold time and sensitivity compared to lysed samples. The LAMP assay was more resilient than traditional qPCR to humic acid in sample, amplifying with up to 100 mg per L of humic acid per reaction compared to 1 mg per L for qPCR. Of the tested field-able concentrations methods, DFA had the lowest coefficient of variation among Dehalobacter spiked groundwater samples and lowest threshold time indicating high capture efficiency and low inhibition. While demonstrated with Dehalobacter, the DFA method can potentially be used for a number of applications requiring field-able, rapid (<60 min) and highly sensitive quantification of microorganisms in environmental water samples.
a b s t r a c tThe present study introduces a new technique using a combined up-flow anaerobic sludge bed (UASB) followed by innovative down-flow hanging non-woven fabric (DHNW) for the treatment of domestic wastewater. The aim of this work is to develop an innovative non-woven packing material that can be used to improve the performance of both UASB and DHNW and other similar techniques for the treatment of wastewater. The packing material could be produced from waste plastic bottles, thus considerable part of solid waste can be reduced, recycled and applied in wastewater treatment plant to produce treated reusable effluent. The primary treatment was carried out using packed and classical UASB reactor (in parallel manner). The quality of the packed UASB effluent was better than that of the classical UASB reactor. Consequently, the effluent of the packed UASB reactor was fed directly to the DHNW reactor. The source of wastewater was the domestic wastewater from Zeneen's wastewater treatment station. The hydraulic residence time (HRT) of the UASB reactors was 6 h. The performance of the combined packed UASB/DHNW showed reduction of COD, BOD and TSS from 349.6, 260.6 and 171.3 to 44, 24 and 27 mg/L, respectively. The fecal coliform (FC)count was reduced by 3 log units using the combined packed UASB/DHNW system. The results indicated that polyethylene terephthalate (PET) spun-bond non-woven fabric can offer a cost effective solution as well as durable and efficient packing material for wastewater treatment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.