Occurrence of veterinary drugs and resistance genes during anaerobic digestion of poultry and cattle manures

Biotransformation of chloramphenicol by enriched bacterial consortia and the newly isolated bacterial strain Bordetella sp. C3: Detoxifying biotransformation pathway and its potential application in agriculture

Limited sources of consortia/pure cultures that degrade chloramphenicol (CAP) and the incomplete biodegradation profiles of CAP hinder the remediation of CAP pollution. In this study, two CAP-degrading consortia (designated as CM and PM) were obtained after long-term acclimation, and Alcaligenaceae and Enterobacteriaceae enriched in CM and PM, respectively. Notably, Bordetella sp. C3, a new isolate belonging to the family Alcaligenaceae, was isolated from CM and capable of degrading 85.7 % 10 mg/L CAP at 30 ℃ and pH 7 in 10 d. The biotransformation of CAP by Bordetella sp. C3 was proposed as a detoxification process, including a novel initial degradation pathway: dechlorination of CAP into AP. Strain C3 can also function as a plant growth-promoting bacterium that solubilizes inorganic phosphate and produces siderophores and indole-3-acetic acid (IAA). This study expands our knowledge of the migration and transformation pathways of CAP and microbial community profiles during acclimatization.

Distinctive effects of graphene oxide and reduced graphene oxide on methane production kinetics and pharmaceuticals removal in anaerobic reactors

Graphene oxide (GO) addition to anaerobic digestion has been suggested to enhance direct electron transfer. The impact of GO (0.075 g GO g-1 VS) and biologically and hydrothermally reduced GO (bio-rGO and h-rGO, respectively) on the methane production kinetics and removal of 12 pharmaceuticals was assessed in Fed-batch reactors. A decrease of 15 % in methane production was observed in the tests with GO addition compared with the control and the h-rGO. However, bio-rGO and h-rGO substantially increased the methane production rate compared to the control tests (+40 %), in the third fed-batch test. Removal of pharmaceuticals was enhanced only during the bio-reduction of GO (1st fed-batch test), whereas once the GO was bio-reduced, it followed a similar trend in the control and h-rGO tests. The addition of GO can enhance the methane production rate and, therefore, reduce the anaerobic treatment time.

Swine manure management by hydrothermal carbonization: Comparative study of batch and continuous operation

Hydrothermal carbonization (HTC) is considered a promising technology for biomass waste management without pre-drying. This study explores the potential for swine manure management by comparing batch and continuous processes, emphasizing the benefits of the continuous mode, particularly for its potential full-scale application. The continuous process at low temperature (180 °C) resulted in a hydrochar with a lower degree of carbonization compared to the batch process, but similar characteristics were found in both hydrochars at higher operating temperatures (230-250 °C), such as C content (∼ 52 wt%), fixed carbon (∼ 24 wt%) and higher calorific value (21 MJ kg-1). Thermogravimetric and combustion analyses showed that hydrochars exhibited characteristics suitable as solid biofuels for industrial use. The process water showed a high content of organic matter as soluble chemical oxygen demand (7-22 g L-1) and total organic carbon (4-10 g L-1), although a high amount of refractory species such as N- and O-containing long aromatic compounds were detected in the process water from the batch process, while the process water from the continuous process presented more easily biodegradable compounds such as acids and alcohols, among others. The longer time required to reach operating temperature in the case of the batch system (longer heating time to reach operating temperature) resulted in lower H/C and O/C ratios compared to hydrochar from the continuous process. This indicates that the dehydration and decarboxylation reactions of the feedstock play a more important role in the batch process. This study shows the efficiency of the continuous process to obtain carbonaceous materials suitable for use as biofuel, providing a solution for swine manure management.

Advanced oxidation and biological integrated processes for pharmaceutical wastewater treatment: A review

The stress of pharmaceutical and personal care products (PPCPs) discharging to water bodies and the environment due to increased industrialization has reduced the availability of clean water. This poses a potential health hazard to animals and human life because water contamination is a great issue to the climate, plants, humans, and aquatic habitats. Pharmaceutical compounds are quantified in concentrations ranging from ng/Lto μg/L in aquatic environments worldwide. According to (Alsubih et al., 2022), the concentrations of carbamazepine, sulfamethoxazole, Lutvastatin, ciprofloxacin, and lorazepam were 616-906 ng/L, 16,532-21635 ng/L, 694-2068 ng/L, 734-1178 ng/L, and 2742-3775 ng/L respectively. Protecting and preserving our environment must be well-driven by all sectors to sustain development. Various methods have been utilized to eliminate the emerging pollutants, such as adsorption and biological and advanced oxidation processes. These methods have their benefits and drawbacks in the removal of pharmaceuticals. Successful wastewater treatment can save the water bodies; integrating green initiatives into the main purposes of actor firms, combined with continually periodic awareness of the current and potential implications of environmental/water pollution, will play a major role in water conservation. This article reviews key publications on the adsorption, biological, and advanced oxidation processes used to remove pharmaceutical products from the aquatic environment. It also sheds light on the pharmaceutical adsorption capability of adsorption, biological and advanced oxidation methods, and their efficacy in pharmaceutical concentration removal. A research gap has been identified for researchers to explore in order to eliminate the problem associated with pharmaceutical wastes. Therefore, future study should focus on combining advanced oxidation and adsorption processes for an excellent way to eliminate pharmaceutical products, even at low concentrations. Biological processes should focus on ideal circumstances and microbial processes that enable the simultaneous removal of pharmaceutical compounds and the effects of diverse environments on removal efficiency.

Recent advances in the biological treatment of wastewater rich in emerging pollutants produced by pharmaceutical industrial discharges

Pharmaceuticals and personal care products present potential risks to human health and the environment. In particular, wastewater treatment plants often detect emerging pollutants that disrupt biological treatment. The activated sludge process is a traditional biological method with a lower capital cost and limited operating requirements than more advanced treatment methods. In addition, the membrane bioreactor combines a membrane module and a bioreactor, widely used as an advanced method for treating pharmaceutical wastewater with good pollution performance. Indeed, the fouling of the membrane remains a major problem in this process. In addition, anaerobic membrane bioreactors can treat complex pharmaceutical waste while recovering energy and producing nutrient-rich wastewater for irrigation. Wastewater characterizations have shown that wastewater's high organic matter content facilitates the selection of low-cost, low-nutrient, low-surface-area, and effective anaerobic methods for drug degradation and reduces pollution. However, to improve the biological treatment, researchers have turned to hybrid processes in which all physical, chemical, and biological treatment methods are integrated to remove various emerging contaminants effectively. Hybrid systems can generate bioenergy, which helps reduce the operating costs of the pharmaceutical waste treatment system. To find the most effective treatment technique for our research, this work lists the different biological treatment techniques cited in the literature, such as activated sludge, membrane bioreactor, anaerobic treatment, and hybrid treatment, combining physicochemical and biological techniques.