Project description:We evaluated the possible mechanisms by which exposures to pulp and paper mill effluents gene expression in the fathead minnow hypothalamus Keywords: Toxicology Sexually mature fathead minnows were exposed to 100% pulp and paper mill effluents for 5 days. Tanks contained 4 females and 2 males. A total 4 tanks per effluents were used in this experiment. TM5, TM6, and KM4 represent different pulp and paper mill effluents from different mills coded for by FPInnovations-Paprican.
Project description:We evaluated the possible mechanisms by which exposures to pulp and paper mill effluents gene expression in the fathead minnow hypothalamus Keywords: Toxicology
Project description:We evaluated the possible mechanisms by which exposure to a sequentially treated pulp and paper mill effluent affects gene expression in the liver of male and female fathead minnows.
Project description:Bacteriophage – host dynamics and interactions are important for microbial community composition and ecosystem function. Nonetheless, empirical evidence in engineered environment is scarce. Here, we examined phage and prokaryotic community composition of four anaerobic digestors in full-scale wastewater treatment plants (WWTPs) across China. Despite relatively stable process performance in biogas production, both phage and prokaryotic groups fluctuated monthly over a year of study period. Nonetheless, there were significant correlations in their α- and β-diversities between phage and prokaryotes. Phages explained 40.6% of total prokaryotic community composition, much higher than the explainable power by abiotic factors (14.5%). Consequently, phages were significantly (P<0.010) linked to parameters related to process performance including biogas production and volatile solid concentrations. Association network analyses showed that phage-prokaryote pairs were deeply rooted, and two network modules were exclusively comprised of phages, suggesting a possibility of co-infection. Those results collectively demonstrate phages as a major biotic factor in controlling bacterial composition. Therefore, phages may play a larger role in shaping prokaryotic dynamics and process performance of WWTPs than currently appreciated, enabling reliable prediction of microbial communities across time and space.
Project description:We evaluated the possible mechanisms by which exposure to a sequentially treated pulp and paper mill effluent affects gene expression in the liver of male and female fathead minnows. Sexually mature fathead minnows were exposed to either river water, which served as our control (C), 10% untreated kraft effluent (UTK), 25% treated kraft effluent (TK) or 100% final effluent (CMO) from a multiprocess pulp and paper mill for 6 days. A total of 4 treatments. Each exposure aquarium consisted of a 42.1 L column that contained individual 5.3 L chambers. Each chamber contained a FHM breeding pair. A total of 3 biological replicates for male and female FHM per treatment were sent for microarray analysis resulting in a total of 24 arrays run as a reference design with a pooled sample of the 6 river water exposed fish serving as the reference sample..
Project description:Bio-augmentation could be a promising strategy to improve processes for treatment and resource recovery from wastewater. In this study, the Gram-positive bacterium Bacillus subtilis was co-cultured with the microbial communities present in wastewater samples with high concentrations of nitrate or ammonium. Glucose supplementation (1%) was used to boost biomass growth in all wastewater samples. In anaerobic conditions, the indigenous microbial community bio-augmented with B. subtilis was able to rapidly remove nitrate from wastewater. In these conditions, B. subtilis overexpressed nitrogen assimilatory and respiratory genes including NasD, NasE, NarG, NarH, and NarI, which arguably accounted for the observed boost in denitrification. Next, we attempted to use the the ammonium- and nitrate-enriched wastewater samples bio-augmented with B. subtilis in the cathodic compartment of bioelectrochemical systems (BES) operated in anaerobic condition. B. subtilis only had low relative abundance in the microbial community, but bio-augmentation promoted the growth of Clostridium butyricum and C. beijerinckii, which became the dominant species. Both bio-augmentation with B. subtilis and electrical current from the cathode in the BES promoted butyrate production during fermentation of glucose. A concentration of 3.4 g/L butyrate was reached with a combination of cathodic current and bio-augmentation in ammonium-enriched wastewater. With nitrate-enriched wastewater, the BES effectively removed nitrate reaching 3.2 mg/L after 48 h. In addition, 3.9 g/L butyrate was produced. We propose that bio-augmentation of wastewater with B. subtilis in combination with bioelectrochemical processes could both boost denitrification in nitrate-containing wastewater and enable commercial production of butyrate from carbohydrate- containing wastewater, e.g. dairy industry discharges. These results suggest that B. subtilis bio-augmentation in our BES promotes simultaneous wastewater treatment and butyrate production.