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This study evaluated various industrial effluents’ effect on irrigation water quality and farm soil near Kombolcha town. Several industries such as brewery, steel iron, textile, and tannery have been installed near the Borkena River that crosses Kombolcha town. Representative samples of irrigation water and farm soil were collected from the upper and down part of Borkena river. The upper site was used as a control as it was not contaminated by industrial effluents. The analysis for selected parameters showed that the downstream irrigation water quality had mean concentrations of pH = 8.54, magnesium (Mg+2) = 5.27 mg/l, carbonate (CO3−2) = 1.25 mg/l, bicarbonate (HCO3−) = 9.10 mg/l, copper (Cu) = 0.21 mg/l, chromium (Cr) = 0.31 mg/l, and cadmium (Cd) = 0.03 mg/l which were above the permissible limit of the Food and Agriculture Organization’s (FAO’s) irrigation water quality standard. The mean concentrations of electric conductivity (EC) = 0.96 ds/m, sodium (Na+) = 3.35 mg/l, chloride (Cl−) = 7.67 mg/l, and total dissolved solids (TDS) = 612.98 mg/l were slightly and moderately restricted for irrigation. Moreover, the concentration of heavy metals, calcium (Ca+2) = 16.61 mg/l, iron (Fe) = 4.25 mg/l, manganese (Mn) = 0.18 mg/l, and lead (Pb) = 0.47 mg/l, was below the permissible limit of the FAO and nonrestricted. However, the mean concentration of EC, HCO3−, Cu, Cr, Cd, and TDS for downstream-irrigated farm soil samples was above the permissible limit of the FAO. The concentration of most selected parameters in downstream farm soil was also decreasing along with depth except pH, CO3−2, and HCO3-. Generally, there is a significant quality difference (at P ≤ 0.05) between the upstream and downstream irrigation water quality on the parameters of Mg+2, Cl−, Pb, and Cu.

The escalating global food waste crisis presents both a challenge and an opportunity for sustainable development. Every year, millions of tons of food are wasted, contributing to environmental degradation and resource inefficiency. This wasted food not only represents a loss of valuable resources but also contributes to significant greenhouse gas emissions when disposed of in landfills. In response to this pressing issue, food waste valorization biorefineries have emerged as a promising solution, transforming waste into valuable bioproducts through innovative biotechnological processes. This review critically examines recent trends in food waste biorefining, focusing on the latest advancements in microbial and enzymatic conversion technologies. Various valorization pathways that convert food waste into biofuels, biochemicals, and bio-based materials are explored, thereby integrating principles of the circular economy to minimize waste and maximize resource utilization. Key developments in the field include the optimization of microbial consortia for enhanced degradation and conversion efficiency, as well as the engineering of enzymes to improve specificity and activity. These advancements have led to significant improvements in the efficiency and feasibility of converting food waste into high-value products. The environmental benefits of these biorefineries are also discussed in depth, encompassing the reduction of greenhouse gas emissions, decreased reliance on fossil fuels, and the mitigation of environmental pollution. By diverting food waste from landfills and transforming it into renewable resources, these biorefineries play a crucial role in promoting environmental sustainability. Despite these advancements, several challenges remain. Feedstock variability affects process consistency, leading to fluctuations in product yield and quality. There is a need for process optimization to improve yield and cost-effectiveness, ensuring that biorefinery operations are economically viable at an industrial scale. Issues related to scalability and industrial implementation, such as the development of infrastructure and supply chains, also pose significant hurdles. By synthesizing current research, this review underscores the considerable potential of food waste biorefineries to contribute to sustainable agriculture and biocatalysis. Critical gaps in knowledge are identified, and areas for future research are proposed, such as developing robust and flexible biorefining systems capable of handling diverse feedstocks and integrating advanced biotechnological tools for process monitoring and control. The review also highlights the importance of interdisciplinary collaboration and public-private partnerships in driving innovation and commercialization in this field. Ultimately, this review aims to provide a comprehensive understanding of the current state of food waste biorefining and to offer a roadmap for future research and industrial implementation. By highlighting the role of these biorefineries in achieving sustainable development goals, the review emphasizes the need for continued research, technological innovation, and supportive policy frameworks. Through these efforts, food waste valorization biorefineries can play a pivotal role in creating a sustainable and resilient future, addressing both environmental and economic challenges posed by food waste. [ABSTRACT FROM AUTHOR]

In the era dominated by plastic, the widespread use of plastic in our daily lives has led to a growing accumulation of its degraded byproducts, such as microplastics and plastic additives like Bisphenol A (BPA). BPA is recognized as one of the earliest man-made substances that exhibit endocrine-disrupting properties. It is frequently employed in the manufacturing of epoxy resins, polycarbonates, dental fillings, food storage containers, infant bottles, and water containers. BPA is linked to a range of health issues including obesity, diabetes, chronic respiratory illnesses, cardiovascular diseases, and reproductive abnormalities. This study examines the bacterial bioremediation of the BPA, which is found in many sources and is known for its hazardous effects on the environment. The metabolic pathways for the breakdown of BPA in important bacterial strains were hypothesized based on the observed altered intermediate metabolites during the degradation of BPA. This review discusses the enzymes and genes involved in the bacterial degradation of BPA. The utilization of naturally occurring microorganisms is the most efficient and cost-effective method due to their selectivity of strains, ensuring sustainability. [ABSTRACT FROM AUTHOR]

SiCf/SiC composites are replacing superalloy components in hot sections of gas turbines. The high-velocity combustion gases in gas turbine hot sections contain water vapor. The mechanism of oxidative water vapor attack on SiC is vastly different from that of oxidation in static dry air. Therefore, it is of paramount importance to study the oxidation of these composites in high-velocity combustion environments. This study focuses on the high-temperature oxidation behavior of SiCf/SiC composites with a BN interfacial coating in both static air and combustion environments. The composite was prepared by the chemical vapor infiltration process (CVI). To elucidate the impact of water vapor in a combustion environment, an oxyacetylene flame apparatus was used. Oxidation of the SiCf/SiC composite was investigated at 1200, 1300 and 1400 °C, for up to 100 h in static dry air, and for up to 24 h in a combustion environment. The microstructure evolution and recession of the composite under combustion environment were investigated by scanning electron microscopy. The oxidation kinetics of the SiCf/SiC composite showed a parabolic nature in static air; however, in the combustion environment the composite showed accelerated mass loss owing to the concurrent effects of oxidation and recession. [ABSTRACT FROM AUTHOR]