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The public widely uses Paracetamol (PCT) as an analgesic drug to reduce pain and fever symptoms in the human body. The COVID-19 pandemic has led to an increase in PCT consumption, resulting in its presence in water bodies and establishing it as a common aquatic environmental pollutant. Conventional methods for PCT removal rely on chemical treatments, which necessitate harsh reaction conditions and incur high operational costs. This study aims to investigate the potential for PCT degradation within the anode environment of the Microbial Fuel Cell (MFC) system, using a consortium of bacteria isolated from sewage sludge. The initial PCT concentration and the pH of the anode environment were varied. The results showed that PCT degradation occurred within 72 hours. The highest PCT removal rate was achieved at elevated concentrations, specifically 28.54 ± 18.84% for an initial PCT concentration of 31.45 mg/L. Furthermore, the pH levels of the anode environment were observed to influence PCT degradation, with the highest degradation rate recorded at 48.69 ± 0.86% at a pH of 8.2. In this study, the highest average power density reached was 1174.42 mW/m2 with an external resistance of 1000 Ω at an initial PCT concentration of 31.45 mg/L. Microbial community analysis was conducted, revealing that Burkholderia sp. dominated the reactor containing PCT. These findings offer valuable insights for the development of more efficient technologies for the removal of PCT from pharmaceutical wastewater using natural microbial communities.

Employing floating treatment wetlands (FTWs) and constructed wetlands (CWs) is one of the most eco-friendly strategies for the bioremediation of water contaminants. Here, the efficiency of FTWs and CWs was compared for the degradation of phenanthrene-contaminated water for the first time. The FTWs and CWs were established by vegetated Phragmites australis in phenanthrene (1000 mg L−1)-contaminated water. Both wetlands were augmented with a bacterial consortium of four bacterial strains: Burkholderia phytofirmans PsJN, Pseudomonas anguiliseptica ITRI53, Arthrobacter oxydans ITRH49, and Achromobacter xylosoxidans ITSI70. Overall, the wetlands removed 91–93% of the phenanthrene whilst the augmentation of the bacterial strains had a synergistic effect. In comparison, the CWs showed a better treatment efficiency, with a 93% reduction in phenanthrene, a 91.7% reduction in the chemical oxygen demand, an 89% reduction in the biochemical oxygen demand, and a 100% reduction in toxicity. The inoculated bacteria were found growing in the shoots, roots, and water of both wetlands, but were comparatively better adapted to the CWs when compared with the FTWs. Similarly, the plants vegetated in the CWs exhibited better growth than that observed in the FTWs. This study revealed that the FTWs and CWs vegetated with P. australis both had promising potential for the cost-effective bioremediation of phenanthrene-contaminated water.

Abstract Anaerobic digestion plays an important role in the gastrointestinal tract and in organic waste treatment. Thermodynamic analysis based on the reaction Gibbs free energy can be used to predict the favorability of some reactions occurring during anaerobic digestion. In this study, we used a thermodynamic approach to evaluating reactions and stoichiometric coefficients of the anaerobic process of in vitro rumen microbiota. The favorability of glucose, butyrate, propionate, and hydrogen utilizations was analyzed by calculating the Gibbs free energy change of each reaction. A previously published Gibbs free energy dissipation method was also used to calculate stoichiometric coefficients of the total metabolism reaction of glucose and hydrogen utilization. For glucose utilization in which the metabolism follows several different pathways, the fraction of glucose following each pathway is estimated by considering the number of electron transfer attributed throughout the catabolism reaction. Glucose utilization always occurs in the system, and the syntrophic correlation among butyrate, propionate, and hydrogen utilizations run well with propionate utilization following the alternative pathway that yields lower hydrogen. The approach applied in this research significantly reduces the stoichiometric coefficients that must be predicted in kinetic modeling. To verify the calculation result, the yield coefficients obtained were then applied in the previous mechanistic model of in vitro rumen microbiota, and the results were compared to the experimental data from literature.

The separation process between 5-hydroxymethylfurfural (HMF) and trace glucose in glucose conversion is important in the biphasic system (aqueous–organic phase), due to the partial solubility property of HMF in water. In addition, the yield of HMF via the dehydration reaction of glucose in water is low (under 50%) with the use of Brønsted acid as a catalyst. Therefore, this study was conducted to optimize the production and separation of products by using a new hydrophobic ionic liquid (IL), which is more selective than water. The new IL (1,3-dibutyl-2-(2-butoxyphenyl)-4,5-diphenyl imidazolium iodide) [DBDIm]I was used as a solvent and was optimized for the dehydration reaction of glucose to make a more selective separation of HMF, levulinic acid (LA), and formic acid (FA). [DBDIm]I showed high performance as a solvent for glucose conversion at 100 °C for 120 min, with a yield of 82.2% HMF, 14.9% LA, and 2.9% FA in the presence of sulfuric acid as the Brønsted acid catalyst.

Proteins are one of the primary building blocks that have significant functional properties to be applied in food and pharmaceutical industries. Proteins could be beneficial in their concentrated products or isolates, of which membrane-based filtration methods such as ultrafiltration (UF) encompass application in broad spectra of protein sources. More importantly, selective enrichment by UF is of immense interest due to the presence of antinutrients that may dominate their perspicuous bioactivities. UF process is primarily obstructed by concentration polarization and fouling; in turn, a trade-off between productivity and selectivity emerges, especially when pure isolates are an ultimate goal. Several factors such as operating conditions and membrane equipment could leverage those pervasive contributions; therefore, UF protocols should be optimized for each unique protein mixture and mode of configuration. For instance, employing charged UF membranes or combining UF membranes with electrodialysis enables efficient separation of proteins with a similar molecular weight, which is hard to achieve by the conventional UF membrane. Meanwhile, some proposed strategies, such as utilizing ultrasonic waves, tuning operating conditions, and modifying membrane surfaces, can effectively mitigate fouling issues. A plethora of advancements in UF, from their membrane material modification to the arrangement of new configurations, contribute to the quest to actualize promising potentials of protein separation by UF, and they are reviewed in this paper.

In this study, imidazole derivative-based new ionic liquids were investigated as corrosion inhibitors. These new ionic liquids (ILs) are 1,3-dipropyl-2-(2-propoxyphenyl)-4,5-diphenylimidazole iodide (IL1) and 1,3-dibutyl-2-(2-butoxyphenyl)-4,5-diphenylimidazole iodide (IL2). The corrosion inhibition effects of two new ILs were observed on carbon steel in brackish water media (1% NaCl solution). Carbon steel coupons were exposed to 1% NaCl solution with various concentrations of ILs. Corrosion inhibition effects were tested by the electrochemical impedance spectroscopy (EIS) method and the Tafel method at various temperatures ranging from 25 °C to 55 °C. The results showed that ILs have potential as corrosion inhibitors and the adsorption mechanisms of IL1 and IL2 on carbon steel surfaces were also determined, which followed the Langmuir adsorption isotherm model. Acquisition of ∆Gads values of IL1 and IL2 were −35.04 and −34.04 kJ/mol, respectively. The thermodynamic data of the ILs show that semi-chemical and or physical adsorptions occurred on carbon steel surfaces.

Due to the growing energy demands and increased concern over environmental deterioration and energy climate catastrophe, bio-energy based mechanisms had gained interest over recent years and had attained acknowledgment as the “greener” energy self-sustainable technologies of the future. A new micro-fluidic bio-solar cell modeling and their integration using COMSOL multi-physics have been proposed in order to convert solar energy into bioelectricity. Synechocystis PCC6803 is used as the microbial source due to its electrical property for generating electrons through an anodic chamber. Using COMSOL multi-physics platform, the microfluidic bio-solar cell was designed with five functioning layers. Each layer is been assigned with the suitable electrical/electrode properties of the polymer and the anodic chamber layer been assigned with the properties of the microalgae. Finally, the microfluidic bio-solar cell was modeled to create interfaces between optical and electrical physics in order to determine their material transport, heat transfer, electrochemical behavior, current density and voltage distribution behavior of the microfluidic bio-solar cell. The open circuit voltage of about 0.42 V is been obtained with 80% of absorption capacity. This modeling can be further developed into an extensible bio-solar panel by fabricating it using a microfluidic chamber for further application enhancement, which can replace inorganic solar cells with bio-solar cells for an eco-friendly environment with less production cost. [ABSTRACT FROM AUTHOR]