Reviews in Environmental Science and Bio/Technology最新文献

Worldwide, 40% population consumes wheat (Triticum aestivum L.) as a staple food that is low in zinc (Zn) content. Zn deficiency is a major micronutrient disorder in crop plants and humans worldwide, adversely impacting agricultural productivity, human health and socio-economic concern. Globally, the entire cycle of increasing the Zn concentration in wheat grains and its ultimate effect on grain yield, quality, human health & nutrition and socio-economic status of livelihood is less compared. So the present studies were planned to compare the worldwide studies for the alleviation of Zn malnutrition. Zn intake is affected by numerous factors from soil to crop, crop to food and food to humans. The post-harvest fortification, diversification in dietary habits, mineral supplementation and biofortification are various possible approaches to enhance the Zn concentration in food. The wheat grains Zn is influenced by the Zn application technique and time concerning crop developmental stages. The use of soil microorganisms mobilize unavailable Zn, and improve Zn assimilation, plant growth, yield and Zn content in wheat. Climate change can have an inverse impact on the efficiency of agronomic biofortification methods due to a reduction in grain-filling stages. Agronomic biofortification can improve Zn content, crop yield as well as quality and ultimately, have a positive impact on human nutrition, health and socioeconomic status of livelihood. Though bio-fortification research has progressed, some crucial areas are still needed to be addressed or improved to achieve the fundamental purpose of agronomic biofortification.

Bacillus thuringiensis (Bt) and its products are commonly used to control insect pests. The main issue with these bacteria is their limited field stability. These constraints fueled interest in using several molecular, biological, and biotechnological techniques to develop new recombinant Bt toxins with a broader insect spectrum, improved environmental stability and more efficient delivery of toxins to pest insects control. However, the potential environmental impact of using recombinant Bt strains and genetically engineered Bt crops includes gene flows into wild species and their unintended consequences on parasitoids and predators. The development of new hybrid/mutated Bt insecticidal toxins, with enhanced insecticidal activity and/or a broader spectrum of target insects, will continue to be a useful strategy for controlling resistant insect pests and delaying resistance evolution. Furthermore, the use of other genes encoding non-Bt proteins with insecticidal properties and different modes of action, such as protease inhibitors, lectins, cholesterol oxidases and chitinases, isolated from various sources will be critical in providing new weapons for the fight against insect damage.

This review thoroughly describes recent advances and the most recent updates in the new potential applications of Bt, making it a remarkable new cell factory that can be employed to control pests.

The growing global population and higher living standards instantly demand the transition in the direction of a sustainable food system. A substantial section of means and agricultural lands are presently committed to protein-rich feed production to rear livestock for human consumption. Conversely, accelerated farming activities and the food industry have rendered a drastic increase in waste which impair the economic and environmental sustainability of the ecosystem. This situation emerges the need for developing an integrated technology for waste management and to improve sustainability footprints. Microbial protein (MP) production based on renewable electron and carbon sources has the potential as a substitute protein source. MP production for animal feed use is growing fast and is derived from bacteria, algae, and fungi including yeast. MP produced from all types of microbes is currently commercialized and in use. However, novel methods and processes are also under investigation to make MP production more economical and sustainable. Current research on MP has concentrated on the valorization of waste materials by using high protein content-containing microorganisms, which can then be used in animal feed. Using such kind of integrated approach, the agroindustry waste resources upcycling can contribute towards finding sustainable, cheaper, and environment-friendly protein sources. This review first describes the potential waste feedstock for MP production and summarizes the recent progress in the application of MP-producing microorganisms including fungus, yeast, bacteria, and phototrophic microbes. Bioprocesses, and production technology advances for MP production have been explored and discussed in detail. Finally, the MP application as animal feed, its challenges, and future perspectives in research have been evaluated.

Water quality index (WQI) is one of the most used tools to describe water quality. It is based on physical, chemical, and biological factors that are combined into a single value that ranges from 0 to 100 and involves 4 processes: (1) parameter selection, (2) transformation of the raw data into common scale, (3) providing weights and (4) aggregation of sub-index values. The background of WQI is presented in this review study. the stages of development, the progression of the field of study, the various WQIs, the benefits and drawbacks of each approach, and the most recent attempts at WQI studies. In order to grow and elaborate the index in several ways, WQIs should be linked to scientific breakthroughs (example: ecologically). Consequently, a sophisticated WQI that takes into account statistical methods, interactions between parameters, and scientific and technological improvement should be created in order to be used in future investigations.

Poor indoor air quality has become of particular concern within the built environment due to the time people spend indoors, and the associated health burden. Volatile organic compounds (VOCs) off-gassing from synthetic materials, nitrogen dioxide and harmful outdoor VOCs such benzene, toluene, ethyl-benzene and xylene penetrate into the indoor environment through ventilation and are the main contributors to poor indoor air quality with health effects. A considerable body of literature over the last four decades has demonstrate the removal of gaseous contaminants through phytoremediation, a technology that relies on plant material and technologies to remediate contaminated air streams. In this review we present a state-of-the-art on indoor phytoremediation over the last decade. Here we present a review of 38 research articles on both active and passive phytoremediation, and describe the specific chemical removal efficiency of different systems. The literature clearly indicates the efficacy of these systems for the removal of gaseous contaminants in the indoor environment, however it is evident that the application of phytoremediation technologies for research purposes in-situ is currently significantly under studied. In addition, it is common for research studies to assess the removal of single chemical species under controlled conditions, with little relevancy to real-world settings easily concluded. The authors therefore recommend that future phytoremediation research be conducted both in-situ and on chemical sources of a mixed nature, such as those experienced in the urban environment like petroleum vapour, vehicle emissions, and mixed synthetic furnishings off-gassing. The assessment of these systems both in static chambers for their theoretical performance, and in-situ for these mixed chemical sources is essential for the progression of this research field and the widespread adoption of this technology.

Production of hydrogen as carbon-free energy from renewable organic waste biomasses has been adopted for the long-term sustainability of a circular economy through various chemical and biological conversion processes. Conversion of waste biomasses to hydrogen provides dual benefits of low-cost energy-dense biofuel production and simultaneous waste reduction in eco-friendly valorization. Advancements in existing chemical and biological processes through light-induced photoreformation and microbial syntrophy-mediated metabolic induction in fermentation, respectively, facilitated holistic conversion of biowaste for maximum recovery of hydrogen by minimizing by-product generation. This review focuses on various thermochemical, photocatalytic reformation, and biological processes involving direct or indirect conversion of solid organic biomasses to hydrogen and their possible technological advancements to generate waste-to-value-added products. The techno-economic assessment describes the feasibility of waste biomass-derived hydrogen production over other technologies for industrial implementation.

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In light of the rising presence of contaminants of emerging concern in water streams, in recent decades, advanced oxidation processes have received significant research interest, as the generation of oxidative radicals allows for the effective degradation of recalcitrant compounds. This review paper provides insights into the most relevant generation methods of several oxidative species, with a main emphasis on hydroxyl, sulfate, chlorine and iodine radicals. Understanding the strengths and pitfalls of each generation route is essential to set the baseline for future industrial applications. To this end, this review presents a comprehensive summary of how different techniques result in distinct radical types, and in addition to the principles and mechanisms of formation, the environmental and economic aspects behind the different methods are discussed.

Progressively and projected integration of rare earth metals (REMs) in modern technologies, especially in the clean energy, consumer electronics, aerospace, automotive, and defense sectors, place REMs as critical raw materials in the supply chain and strategic metal from the fourth industrial revolution perspective. Current REM production from the primary mineral resources in the supply chain versus industrial demand is at a bottleneck. Alternatively, REM-bearing anthropogenic wastes are pertinent and potent to addressing the critical supply chain bottleneck. Although secondary REM resources are prudent to address the critical supply chain bottleneck, the absence of effective and efficient technologies to recover these REMs from anthropogenic waste imposes challenges and provides opportunities. Hence, this review analyses and discusses the significance of anthropogenic wastes for REM recovery, the status of recycling technologies for sustainable valorization of REMs, challenges, and opportunities. The current review covers the potential quantitative REM wealth locked in various anthropogenic waste like (i) spent rare earth permanent magnets, (ii) spent batteries, (iii) spent tri-band REM phosphors, (iv) bauxite industry residue red mud, (v) blast furnace slag and (v) coal mines, and coal byproducts and status of valorization technologies for circularizing the REMs. In industrial waste like red mud, steelmaking slag, blast furnace slag, and coal fly ash typically 109,000, 2000, 39,000, and 354,000 tons of REM get scrapped, respectively, in a conservative estimation. In the years 2020 and 2021, respectively, 240,000 and 280,000 tons of REM were produced by mine production in contrast to 504,000 tons of REM that were scrapped with REM-bearing industrial waste. This review revealed that total REM currently getting scrapped with anthropogenic waste versus projected REM demand for the years 2022, 2023, 2024, and 2025 could be standing at 2.66, 2.51, 2.37, and 2.23, respectively. Our investigation revealed that efficient recovery of REMs from anthropogenic waste is significant and promising but associated with challenges like lack of industrial-scale valorization process, lack of a clear strategy, road map, policy, effort, funding, and diversified research.

Iron (Fe) oxides can rapidly recrystallize in the presence of aqueous Fe(II) (Fe(II)_aq) under anoxic conditions. Since different Fe oxides have diverse affinities and redox reactivities for metal(loid)s, nutrients, and organic matters, recrystallization of Fe oxides significantly alters their speciation and environmental behavior. Therefore, the major reaction steps, rates, and influencing factors of Fe(II)_aq-catalyzed recrystallization have gained increasing attention. This paper aims to review the latest advances, especially in redox cycling between Fe(II)_aq and Fe oxide and in the kinetics of Fe atom exchange. The mineralogical recrystallization pathways and intermediate processes of different Fe oxides when exposed to Fe(II)_aq are discussed. The influencing factors such as morphological natures of Fe oxides and typical environmental substances governing the kinetics of isotopic exchange between Fe(II)_aq and Fe oxides are summarized. Several major analytical methodologies in this realm are also illustrated. Finally, some unsolved issues and future research directions in the field of Fe(II)_aq-catalyzed Fe oxide recrystallization are outlined.

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