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Use of pharmaceutical products has seen a tremendous increase in the recent decades. It has been observed that more than thirty million tons of pharmaceuticals are consumed worldwide. The used pharmaceutical products are not completely metabolized in human and animal body. Therefore, they are excreted to the environment and remain there as persistent organic chemicals. These compounds emerge as toxic contaminants in water and affect the human metabolism directly or indirectly. This literature review is an endeavour to understand the origin, applications and current advancement in the removal of pharmaceuticals from the environment. It discusses about the pharmaceuticals used in medical applications such diagnosis and disease treatment. In addition, it discusses about the recent approaches applied in pharmaceutical removal including microbial fuel cells, biofiltration, and bio nanotechnology approaches. Moreover, the challenges associated with pharmaceutical removal are presented considering biological and environmental factors. The review suggest the potential recommendations on pharmaceutical removal.

Electrochemical pretreatment (EPT) is an efficient technology to improve volatile fatty acids (VFAs) production during anaerobic fermentation of waste activated sludge (WAS). This study investigated the co-effects of different current intensities, electrolyte NaCl dosage and pretreatment time for promoting VFAs production. The results showed that it was considerably enhanced by 51.6 % when EPT was performed at 1.0 A, 1.0 g/L and 60 min, and response surface methodology strategy adjusted the optimal EPT conditions to 1.0 A, 1.2 g/L and 66 min. The potential mechanisms were proposed that EPT at optimal conditions greatly enhanced solubilization and hydrolysis of WAS and selectively inactivated methanogens, causing the enrichment of acidogenic bacteria (i.e., Lactobacillus, Saccharimonadales, Tet-rasphaera and Prevotella) due to generated reactive chlorine species. Finally, the economic analysis indicated the promising application potential with the profit of EPT at optimal conditions increasing by 36.0 %.

Microplastics are the small fragments of the plastic molecules which find their applications in various routine products such as beauty products. Later, it was realized that it has several toxic effects on marine and terrestrial organisms. This review is an approach in understanding the microplastics, their origin, dispersal in the aquatic system, their biodegradation and factors affecting biodegradation. In addition, the paper discusses the major engineering approaches applied in microbial biotechnology. Specifically, it reviews microbial genetic engineering, such as PET-ase engineering, MHET-ase engineering, and immobilization approaches. Moreover, the major challenges associated with the plastic removal are presented by evaluating the recent reports available.

QC 20210331

An ever increasing demand for animal protein products has posed serious challenges for managing the increasing quantities of livestock manure. The choice of treatment technologies is still a complicated task and considerable debates over this issue still continue. To build a clearer picture of manure treatment framework, this study was conducted to review the most frequently employed manure management technologies from their state of the art, challenges, sustainability, environmental regulations and incentives, and improvement strategies perspectives. The results showed that most treatment technologies have focused on the solid fraction of manure while the liquid fraction still remains a potential environmental threat. Compared to other waste to energy solutions, anaerobic digestion is the most mature technology to upgrade manure's organic matter into renewable energy, however the problems associated with high investment costs, operating parameters, manure collection, and digestate management have hindered its developments in rural areas in developing countries. Bio-oil production through hydrothermal liquification is also a promising solution, as it can directly convert the wet manure into biofuel. However, lipid-poor nature of manure, operational difficulties, and the need for downstream process to remove nitrogenous compounds from the final product necessitate further research. Livestock manure management (both solid and liquid fractions) under biorefinery approach seems an inevitable solution for future sustainable development to meet circular bioeconomy requirements. Much research is still required to establish a systematic framework based on regional requirements to develop an integrated manure nutrient recycling and manure management planning with minimum environmental risks and maximum profit.

An ever increasing demand for animal protein products has posed serious challenges for managing the increasingquantities of livestock manure. The choice of treatment technologies is still a complicated task and considerabledebates over this issue still continue. To build a clearer picture of manure treatment framework, this study wasconducted to review the most frequently employed manure management technologies from their state of the art,challenges, sustainability, environmental regulations and incentives, and improvement strategies perspectives.The results showed that most treatment technologies have focused on the solid fraction of manure while theliquid fraction still remains a potential environmental threat. Compared to other waste to energy solutions,anaerobic digestion is the most mature technology to upgrade manure’s organic matter into renewable energy,however the problems associated with high investment costs, operating parameters, manure collection, anddigestate management have hindered its developments in rural areas in developing countries. Bio-oil productionthrough hydrothermal liquification is also a promising solution, as it can directly convert the wet manure intobiofuel. However, lipid-poor nature of manure, operational difficulties, and the need for downstream process toremove nitrogenous compounds from the final product necessitate further research. Livestock manure management(both solid and liquid fractions) under biorefinery approach seems an inevitable solution for futuresustainable development to meet circular bioeconomy requirements. Much research is still required to establish asystematic framework based on regional requirements to develop an integrated manure nutrient recycling andmanure management planning with minimum environmental risks and maximum profit.