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The escalating challenges posed by seafood waste generated by the fishing and aquaculture industries underscore the urgent need for innovative solutions that promote both environmental conservation and economic viability within the seafood sector. Seafood waste biorefinery emerges as a promising solution, offering the potential to transform waste materials into valuable products. However, it is essential to recognize that seafood waste biorefinery operations also entail environmental impacts that warrant careful consideration. Environmental assessment tools like Life Cycle Assessment (LCA) provide a valuable framework for assessing these impacts comprehensively. This review critically examines LCA studies in seafood waste biorefinery, focusing on key concepts, emerging technologies, and potential product avenues. Despite the growing body of research in this area, direct comparisons between published studies prove challenging due to discrepancies in feedstocks, processing techniques, value-added products, and LCA methodologies. Nevertheless, the findings consistently demonstrate significant reductions in environmental impacts achieved through seafood waste biorefinery processes. The selection of technologies significantly influences both product quality and sustainability measures. High energy consumption, including diesel fuel consumption in fishing vessels and electricity consumption in processing steps, should be carefully considered and reduced to mitigate associated environmental impacts. In conclusion, while seafood waste biorefinery processes hold significant promise for providing environmental and economic benefits, substantial challenges remain. This review provides invaluable insights for researchers, policymakers, and stakeholders, emphasizing the importance of continuous interdisciplinary collaboration and methodological standardization to advance sustainable waste management practices in the seafood industry., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Competing Interests: Declaration of interests Thirteen of the authors (ZA, S-CH, LJ, AM, CO, MO, JP, YP-S, DS, LB-V, MRo, MW, and HW) were compensated for their time while drafting and developing the Lancet Countdown's report. LC was supported by a grant from the National Heart, Lung, and Blood Institute of the National Institutes of Health. CD received funding from the European Research Council (FLORA, grant number 101039402). RD was supported by a grant from the High Tide Foundation and subcontracts on funds from the Wellcome Trust and US Centers for Disease Control and Prevention. GG-S received funding from the UK National Institute for Health and Care Research for the Global Health Research Group on Diet and Activity (NIHR133205, with sub-award contract number G109900-SJ1/171 with the University of Cambridge). SHG's research was supported by the National Research Foundation, Prime Minister's Office, Singapore, under its Campus for Research Excellence and Technological Enterprise programme (grant number NRF2019-THE001-0006). JJH was supported by two grants from the Wellcome Trust and a grant from the US National Science Foundation. RH, RK, and MSo acknowledge funding from Academy of Finland projects HEATCOST (grant 334798) and VFSP-WASE (grant 359421), together with EU Horizon projects FirEUrisk (grant number 101003890) and EXHAUSTION (grant number 820655). OJ was supported by grants from the National Health Medical Research Council (Heat and Health: building resilience to extreme heat in a warming world, GNT1147789); Wellcome Trust (Heat stress in ready-made garment factories in Bangladesh and the Heat inform pregnant study); and Resilience New South Wales (A new heat stress scale for general public); holds a patent for the Environmental Measurement Unit; and has received consulting fees from the National Institutes of Health. HM received funding from the Oak Foundation to support work on climate change through RealZero, is partly funded by the National Institute for Health Research's Comprehensive Biomedical Research Centre at University College London Hospitals, and received fees from Bayer Pharmaceuticals and Chiesl for sustainability consulting. JM-U was supported by grants PID2021-127107NB-I00 from Ministerio de Ciencia e Innovación (Spain) and 2021 SGR 00526 from Generalitat de Catalunya (Spain). JRo's work is supported by the Alexander von Humboldt foundation. RL, JRo, and MRo were supported by Horizon Europe through the IDAlert project (101057554) and UK Research and Innovation (reference number 10056533). RNS reports a contract with Massachusetts General Hospital. MSo and AU were supported by the Finnish Foreign Ministry project IBA-ILMA (grant number VN/13798/2023). MSp was supported by funding from the Wellcome Trust, through Our Planet Our Health (Livestock, Environment and People, award number 205212/Z/16/Z) and a Wellcome Career Development Award (Towards the full cost of diets, award number 225318/Z/22/Z). JDSh was supported by the Canadian Institutes of Health Research, the Commonwealth Fund, and the Emergency Care Research Institute and has received consulting fees from the Institute for Healthcare Research. JT was supported by the Research Council of Finland (T-Winning Spaces 2035 project), the UK Medical Research Council (PICNIC project), and the Finnish Ministry of the Environment (SEASON project). JB is employed as a consultant by the Global Climate and Health Alliance. ML received consulting fees from YarCom for advisory services and was supported by general use gifts awarded to the Center on Global Energy Policy at Columbia University, USA. JMil acknowledges consulting fees from the C40 Climate Leadership Group. CZ-C received a consultancy from the University of Alberta and was supported by contracts with her university (Universidad Peruana Cayetano Heredia), University of Leeds, WHO, and the Wellcome Trust; she was also supported by a letter of agreement between her university and the Food and Agriculture Organization's Indigenous Peoples Unit. MD was supported by the Wellcome Trust via the Complex Urban Systems for Sustainability and Health project (grants 205207/Z/16/Z and 209387/Z/17/Z). IH, S-CH, MRo, CT, and RL were supported by the Horizon Europe CATALYSE project (CATALYSE grant number 101057131, HORIZON-HLTH-2021-ENVHLTH-02, with UK Research and Innovation reference number 10041512). The work of YH, YL, DT, and QZ was supported by the National Aeronautics and Space Administration's Earth Action programme (grant number 80NSSC21K0507). AJP was supported by the Bezos Earth Fund and the Schmidt Family Foundation. ER and SD were supported by a Process-based models for climate impact attribution across sectors (PROCLIAS) grant (COST Action PROCLIAS grant CA19139), funded by European Cooperation in Science and Technology. All other authors declare no competing interests.

Anthocyanins, natural plant pigments responsible for the vibrant hues in fruits, vegetables, and flowers, boast antioxidant properties with potential human health benefits. However, their susceptibility to degradation under conditions such as heat, light, and pH fluctuations necessitates strategies to safeguard their stability. Recent investigations have focused on exploring the interactions between anthocyanins and biomacromolecules, specifically proteins and polysaccharides, with the aim of enhancing their resilience. Notably, proteins like soy protein isolate and whey protein, alongside polysaccharides such as pectin, starch, and chitosan, have exhibited promising affinities with anthocyanins, thereby enhancing their stability and functional attributes. High-pressure processing (HPP), emerging as a non-thermal technology, has garnered attention for its potential to modulate these interactions. The application of high pressure can impact the structural features and stability of anthocyanin-protein/polysaccharide complexes, thereby altering their functionalities. However, caution must be exercised, as excessively high pressures may yield adverse effects. Consequently, while HPP holds promise in upholding anthocyanin stability, further exploration is warranted to elucidate its efficacy across diverse anthocyanin variants, macromolecular partners, pressure regimes, and their effects within real food matrices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study assesses the environmental impact of pine chip-based biorefinery processes, focusing on bioethanol, xylonic acid, and lignin production. A cradle-to-gate Life Cycle Assessment (LCA) is employed, comparing a novel biphasic pretreatment method (p-toluenesulfonic acid (TsOH)/pentanol, Sc-1) with conventional sulfuric acid pretreatment (H 2 SO 4 , Sc-2). The analysis spans biomass handling, pretreatment, enzymatic hydrolysis, yeast fermentation, and distillation. Sc-1 yielded an environmental impact of 1.45E+01 kPt, predominantly affecting human health (96.55%), followed by ecosystems (3.07%) and resources (0.38%). Bioethanol, xylonic acid, and lignin contributed 32.61%, 29.28%, and 38.11% to the total environmental burdens, respectively. Sc-2 resulted in an environmental burden of 1.64E+01 kPt, with a primary impact on human health (96.56%) and smaller roles for ecosystems (3.07%) and resources (0.38%). Bioethanol, xylonic acid, and lignin contributed differently at 22.59%, 12.5%, and 64.91%, respectively. Electricity generation was predominant in both scenarios, accounting for 99.05% of the environmental impact, primarily driven by its extensive usage in biomass handling and pretreatment processes. Sc-1 demonstrated a 13.05% lower environmental impact than Sc-2 due to decreased electricity consumption and increased bioethanol and xylonic acid outputs. This study highlights the pivotal role of pretreatment methods in wood-based biorefineries and underscores the urgency of sustainable alternatives like TsOH/pentanol. Additionally, adopting greener electricity generation, advanced technologies, and process optimization are crucial for reducing the environmental footprint of waste-based biorefineries while preserving valuable bioproduct production., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Waste-to-energy conversion presents a pivotal strategy for mitigating the energy crisis and curbing environmental pollution. Pyrolysis is a widely embraced thermochemical approach for transforming waste into valuable energy resources. This study delves into the co-pyrolysis of terrestrial biomass (potato peel) and marine biomass (Sargassum angastifolium) to optimize the quantity and quality of the resultant bio-oil and biochar. Initially, thermogravimetric analysis was conducted at varying heating rates (5, 20, and 50 °C/min) to elucidate the thermal degradation behavior of individual samples. Subsequently, comprehensive analyses employing FTIR, XRD, XRF, BET, FE-SEM, and GC-MS were employed to assess the composition and morphology of pyrolysis products. Results demonstrated an augmented bio-oil yield in mixed samples, with the highest yield of 27.1 wt% attained in a composition comprising 75% potato peel and 25% Sargassum angastifolium. As confirmed by GC-MS analysis, mixed samples exhibited reduced acidity, particularly evident in the bio-oil produced from a 75% Sargassum angastifolium blend, which exhibited approximately half the original acidity. FTIR analysis revealed key functional groups on the biochar surface, including O-H, CO, and C-O moieties. XRD and XRF analyses indicated the presence of alkali and alkaline earth metals in the biochar, while BET analysis showed a surface area ranging from 0.64 to 1.60 m 2 /g. The favorable characteristics of the products highlight the efficacy and cost-effectiveness of co-pyrolyzing terrestrial and marine biomass for the generation of biofuels and value-added commodities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Competing Interests: Declaration of interests 14 of the authors (MRo, MWa, LJ, MBO'H, CO, HW, CdN, HK, PL, DS, CG, ZA, MY-G, and KRvD) were compensated for their time while drafting and developing the Lancet Countdown's report. OG was supported by the EU Horizon Grant: Climate Action To Advance Healthy Societies in Europe (Project 101057131–CATALYSE), for which there is overlap of data collection and preprocessing with the materials submitted in this report. MSp was supported by the Wellcome Trust Livestock, Environment and People (grant number 205212/Z/16/Z) and Wellcome Trust (grant number 225318/Z/22/Z). JT was supported by the Academy of Finland grants for the T-Winning (grant number 353327). CD was supported by the UK Natural Environment Research Council Independent Research Fellowship (grant number NE/N01524X/1), which ended in 2021, and by the European Research Council starting grant FLORA (grant number 101039402). OJ was supported by the NHMRC Investigator Grant entitled Heat and Health: Building resilience to extreme heat in a warming world (GNT20009507), the Wellcome Trust grant Heat stress in ready-made garment factories in Bangladesh (216059/Z/19/Z), and the Resilience New South Wales grant A new heat stress scale for general public (PJ-0000850). YL was supported by funding from the National Aeronautics and Space Administration (grant number: 80NSSC21K0507) for the wildfire population exposure and fire danger indicators. TO and IH were supported by the UK Research and Innovation Engineering and Physical Sciences Research Council Centre for Research in Energy Demand Solutions (grant number EP/R035288/1). MRo was supported by funding from IDAlert project (UK Research and Innovation project reference number 10056533). KB was supported by funding from the National Institute for Health and Care Research (NIHR) Centre on Non-communicable Diseases and Environmental Change (NIHR203247). All other authors declare no competing interests. The authors alone are responsible for the views expressed in this Commission, and they do not necessarily represent the views, decisions, or policies of the institutions with which they are affiliated.

Life cycle assessment was used to evaluate the environmental impacts of phytoplanktonic biofuels as possible sustainable alternatives to fossil fuels. Three scenarios were examined for converting planktonic biomass into higher-value commodities and energy streams using the alga Scenedesmus sp. and the cyanobacterium Arthrospira sp. as the species of interest. The first scenario (Sc-1) involved the production of biodiesel and glycerol from the planktonic biomass. In the second scenario (Sc-2), biodiesel and glycerol were generated from the planktonic biomass, and biogas was produced from the residual biomass. The process also involved using a catalyst derived from snail shells for biodiesel production. The third scenario (Sc-3) was similar to Sc-2 but converted CO 2 from the biogas upgrading to methanol, which was then used in synthesizing biodiesel. The results indicated that Sc-2 and Sc-3 had a reduced potential (up to 60 % less) for damaging human health compared to Sc-1. Sc-2 and Sc-3 had up to 61 % less environmental impact than Sc-1. Sc-2 and Sc-3 reduced the total cumulative exergy demand by up to 44 % compared to Sc-1. In conclusion, producing chemicals and utilities within the biorefinery could significantly improve environmental sustainability, reduce waste, and diversify revenue streams., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

The livestock industry needs to use crop straws that are highly digestible to improve feed productivity and reduce ruminal methane emissions. Hence, this study aimed to use the ozonation and pelleting processes to enhance the digestibility and reduce the ruminal methane emissions of wheat straw enriched with two nitrogen sources (i.e., urea and heat-processed broiler litter). Various analyses were conducted on the pellets, including digestibility indicators, mechanical properties, surface chemistry functionalization, chemical-spectral-structural features, and energy requirements. For comparison, loose forms of the samples were also analyzed. The nitrogen-enriched ozonated wheat straw pellets had 43.06 % lower lignin, 28.30 % higher gas production for 24 h, 12.28 % higher metabolizable energy, 13.78 % higher in vitro organic matter digestibility for 24 h, and 28.81 % higher short-chain fatty acid content than the nitrogen-enriched loose sample. The reduction of methane emissions by rumen microorganisms of nitrogen-enriched wheat straw by ozonation, pelleting, and ozonation-pelleting totaled 89.15 %, 23.35 %, and 66.98 %, respectively. The ozonation process resulted in a 64 % increase in the particle density, a 5.5-time increase in the tensile strength, and a 75 % increase in the crushing energy of nitrogen-enriched wheat straw. In addition, ozone treatment could also reduce the specific and thermal energy consumption required in the pelleting process by 15.10 % and 7.61 %, respectively., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The increasing emphasis on the development of green replacements to traditional organic solvents and ionic liquids (ILs) can be attributed to the rising concerns over human health and detrimental impacts of conventional solvents towards the environment. A new generation of solvents inspired by nature and extracted from plant bioresources has evolved over the last few years, and are referred to as natural deep eutectic solvents (NADES). NADES are mixtures of natural constituents like sugars, polyalcohols, sugar-based alcohols, amino acids and organic acids. Interest in NADES has exponentially grown over the last eight years, which is evident from an upsurge in the number of research projects undertaken. NADES are highly biocompatible as they can be biosynthesized and metabolized by nearly all living organisms. These solvents pose several noteworthy advantages, such as easy synthesis, tuneable physico-chemical properties, low toxicity, high biodegradability, solute sustainability and stabilization and low melting point. Research on the applicability of NADES in diverse areas is gaining momentum, which includes as - media for chemical and enzymatic reactions; extraction media for essential oils; anti-inflammatory and antimicrobial agent; extraction of bioactive composites; as chromatographic media; preservatives for labile compounds and in drug synthesis. This review gives a complete overview of the properties, biodegradability and toxicity of NADES which we propose can assist in further knowledge generation on their significance in biological systems and usage in green and sustainable chemistry. Information on applications of NADES in biomedical, therapeutic and pharma-biotechnology fields is also highlighted in the current article along with the recent progress and future perspectives in novel applications of NADES., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Depending on its physicochemical properties and antibacterial activities, chitosan can have a wide range of applications in food, pharmaceutical, medicine, cosmetics, agriculture, and aquaculture. In this experimental study, chitosan was extracted from shrimp waste through conventional extraction, microwave-assisted extraction, and conventional extraction under microwave process conditions. The effects of the heating source on the physicochemical properties and antibacterial activity were investigated. The results showed that the heating process parameters affected the physicochemical properties considerably. The conventional procedure yielded high molecular weight chitosan with a 12.7 % yield, while the microwave extraction procedure yielded a porous medium molecular weight chitosan at 11.8 %. The conventional extraction under microwave process conditions led to medium molecular weight chitosan with the lowest yield (10.8 %) and crystallinity index (79 %). Antibacterial assessment findings revealed that the chitosan extracted using the conventional method had the best antibacterial activity in the agar disk diffusion assay against Listeria monocytogenes (9.48 mm), Escherichia coli. (8.79 mm), and Salmonella Typhimurium (8.57 mm). While the chitosan obtained by microwave-assisted extraction possessed the highest activity against E. coli. (8.37 mm), and Staphylococcus aureus (8.05 mm), with comparable antibacterial activity against S. Typhimurium (7.34 mm) and L. monocytogenes (6.52 mm). Moreover, the minimal inhibitory concentration and minimal bactericidal concentration assays demonstrated that among the chitosan samples investigated, the conventionally-extracted chitosan, followed by the chitosan extracted by microwave, had the best antibacterial activity against the target bacteria., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Mucilages are natural compounds consisting mainly of polysaccharides with complex chemical structures. Mucilages also contain uronic acids, proteins, lipids, and bioactive compounds. Because of their unique properties, mucilages are used in various industries, including food, cosmetics, and pharmaceuticals. Typically, commercial gums are composed only of polysaccharides, which increase their hydrophilicity and surface tension, reducing their emulsifying ability. As a result of the presence of proteins in combination with polysaccharides, mucilages possess unique emulsifying properties due to their ability to reduce surface tension. In recent years, various studies have been conducted on using mucilages as emulsifiers in classical and Pickering emulsions because of their unique emulsifying feature. Studies have shown that some mucilages, such as yellow mustard, mutamba, and flaxseed mucilages, have a higher emulsifying capacity than commercial gums. A synergistic effect has also been shown in some mucilages, such as Dioscorea opposita mucilage when combined with commercial gums. This review article investigates whether mucilages can be used as emulsifiers and what factors affect their emulsifying properties. A discussion of the challenges and prospects of using mucilages as emulsifiers is also presented in this review., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Chitosan is one of the valuable products obtained from crustacean waste. The unique characteristics of chitosan (antimicrobial, antioxidant, anticancer, and anti-inflammatory) have increased its application in various sectors. Besides unique biological properties, chitosan or chitosan-based compounds can stabilize emulsions. Nevertheless, studies have shown that chitosan cannot be used as an efficient stabilizer because of its high hydrophilicity. Hence, this review aims to provide an overview of recent studies dealing with improving the emulsifying properties of chitosan. In general, two different approaches have been reported to improve the emulsifying properties of chitosan. The first approach tries to improve the stabilization property of chitosan by modifying its structure. The second one uses compounds such as polysaccharides, proteins, surfactants, essential oils, and polyphenols with more wettability and emulsifying properties than chitosan's particles in combination with chitosan to create complex particles. The tendency to use chitosan-based particles to stabilize Pickering emulsions has recently increased. For this reason, more studies have been conducted in recent years to improve the stabilizing properties of chitosan-based particles, especially using the electrostatic interaction method. In the electrostatic interaction method, numerous research has been conducted on using proteins and polysaccharides to increase the stabilizing property of chitosan., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Large amounts of agricultural waste, especially marine product waste, are produced annually. These wastes can be used to produce compounds with high-added value. Chitosan is one such valuable product that can be obtained from crustacean wastes. Various biological activities of chitosan and its derivatives, especially antimicrobial, antioxidant, and anticancer properties, have been confirmed by many studies. The unique characteristics of chitosan, especially chitosan nanocarriers, have led to the expansion of using chitosan in various sectors, especially in biomedical sciences and food industries. On the other hand, essential oils, known as volatile and aromatic compounds of plants, have attracted the attention of researchers in recent years. Like chitosan, essential oils have various biological activities, including antimicrobial, antioxidant, and anticancer. In recent years, one of the ways to improve the biological properties of chitosan is to use essential oils encapsulated in chitosan nanocarriers. Among the various biological activities of chitosan nanocarriers containing essential oils, most studies conducted in recent years have been in the field of antimicrobial activity. It was documented that the antimicrobial activity was increased by reducing the size of chitosan particles in the nanoscale. In addition, the antimicrobial activity was intensified when essential oils were in the structure of chitosan nanoparticles. Essential oils can increase the antimicrobial activity of chitosan nanoparticles with synergistic effects. Using essential oils in the structure of chitosan nanocarriers can also improve the other biological properties (antioxidant and anticancer activities) of chitosan and increase the application fields of chitosan. Of course, using essential oils in chitosan nanocarriers for commercial use requires more studies, including stability during storage and effectiveness in real environments. This review aims to overview recent studies on the biological effects of essential oils encapsulated in chitosan nanocarriers, with notes on their biological mechanisms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The rapid development of the textile industry and improvement of people's living standards have led to the production of cotton textile and simultaneously increased the production of textile wastes. Cotton is one of the most common textile materials, and the waste cotton accounts for 24% of the total textile waste. To effectively manage the waste, recycling and reusing waste cotton are common practices to reduce global waste production. This paper summarizes the characteristics of waste cotton and high-value products derived from waste cotton (e.g., yarns, composite reinforcements, regenerated cellulose fibers, cellulose nanocrystals, adsorptive materials, flexible electronic devices, and biofuels) via mechanical, chemical, and biological recycling methods. The advantages and disadvantages of making high-value products from waste cotton are summarized and discussed. New technologies and products for recycling waste cotton are proposed, providing a guideline and direction for merchants and researchers. This review paper can shed light on converting textile wastes other than cotton (e.g., bast, silk, wool, and synthetic fibers) into value-added products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Microorganisms, such as fungi and bacteria, are crucial players in the production of enzymatic cocktails for biomass hydrolysis or the bioconversion of plant biomass into products with industrial relevance. The biotechnology industry can exploit lignocellulosic biomass for the production of high-value chemicals. The generation of biotechnological products from lignocellulosic feedstock presents several bottlenecks, including low efficiency of enzymatic hydrolysis, high cost of enzymes, and limitations on microbe metabolic performance. Genetic engineering offers a route for developing improved microbial strains for biotechnological applications in high-value product biosynthesis. Sugarcane bagasse, for example, is an agro-industrial waste that is abundantly produced in sugar and first-generation processing plants. Here, we review the potential conversion of its feedstock into relevant industrial products via microbial production and discuss the advances that have been made in improving strains for biotechnological applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this study., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Competing Interests: Declaration of interests CD was supported by the UK Natural Environment Research Council (NE/R010811/1) and the UK Natural Environment Research Council Independent Research Fellowship (NE/N01524X/1) and contributes to the Sustainable and Healthy Food Systems project supported by the Wellcome Trust (205200/Z/16/Z). MD was supported by the Wellcome Trust's Complex Urban Systems for Sustainability and Health (CUSSH) project (209387/Z/17/Z). YL was supported by the US National Aeronautics and Space Administration Applied Sciences Program (80NSSC21K0507). RL was supported by a Royal Society Dorothy Hodgkin Fellowship. MSo was supported by Horizon 2020 project EXHAUSTION (820655) and Academy of Finland HEATCOST (334798). SHG and JKWL were supported by Singapore's National Research Foundation, Singapore's Prime Minister's Office, under its Campus for Research Excellence and Technological Enterprise programme. IH was supported by the UK Research and Innovation (UKRI) Engineering and Physical Sciences Research Council Centre for Research in Energy Demand Solutions (EP/R035288/1) and UKRI APEx (NE/T001887/1). JM was supported by the German Ministry for Education and Research (01LA1826A and 03SFK5J0). ML was supported by the Sloan Foundation. All other authors declare no competing interests.

The world has been grappling with the crisis of the COVID-19 pandemic for more than a year. Various sectors have been affected by COVID-19 and its consequences. The waste management system is one of the sectors affected by such unpredictable pandemics. The experience of COVID-19 proved that adaptability to such pandemics and the post-pandemic era had become a necessity in waste management systems and this requires an accurate understanding of the challenges that have been arising. The accurate information and data from most countries severely affected by the pandemic are not still available to identify the key challenges during and post-COVID-19. The documented evidence from literature has been collected, and the attempt has been made to summarize the rising challenges and the lessons learned. This review covers all raised challenges concerning the various aspects of the waste management system from generation to final disposal (i.e., generation, storage, collection, transportation, processing, and burial of waste). The necessities and opportunities are recognized for increasing flexibility and adaptability in waste management systems. The four basic pillars are enumerated to adapt the waste management system to the COVID-19 pandemic and post-COVID-19 conditions. Striving to support and implement a circular economy is one of its basic strategies., Competing Interests: Declaration of competing interest None., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

A huge amount of palm waste generated daily represents a problematic high-moisture waste to be disposed of, yet it also represents a promising biomass resource to be transformed into a value-added product. A single-mode microwave hydrothermal carbonization process incorporating steam purging was developed and utilised to convert high-moisture palm waste into hydrochar over a range of process temperatures from 150 to 300 °C. The microwave hydrothermal carbonization recorded a shorter process duration (10 min) and prevented the occurrence of hot spots within the reactor. The resulting hydrochar showed up to 94.3 wt% of mass yield, 69.2 wt% of fixed carbon, and 412.3 m 2 /g of surface area. The subsequent application of the hydrochar in de-chlorination of domestic water demonstrated an impressive removal performance of up to 98.9% of free chlorine, exhibiting 435 min of breakthrough time, and 40.0 mg/g of bed capacity in continuous column operation. The results show great promise of microwave hydrothermal carbonization as a desirable approach to produce desirable hydrochar for de-chlorination application., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

Anaerobic fungi (Neocallimastigomycota) are promising lignocellulose-degrading microorganisms that can be exploited by the biofuel industry. While natural production of ethanol by these microorganisms is very low, there is a greater potential for their use in the biogas industry. More specifically, anaerobic fungi can contribute to biogas production by either releasing holocellulose or reducing sugars from lignocelluloses that can be used as a substrate by bacteria and methanogens involved in the anaerobic digestion (AD) process or by metabolizing acetate and formate that can be directly consumed by methanogens. Despite their great potential, the appropriate tools for engineering anaerobic fungi have not been established yet. The first section of this review justifies how the biofuel industry can benefit from using anaerobic fungi and is followed by their taxonomy. In the third section, the possibility of using anaerobic fungi for the consolidated production of bioethanol is briefly discussed. Nevertheless, the main focus of this review is on the upstream and mainstream effects of bioaugmentation with anaerobic fungi on the AD process. The present review also scrutinizes the constraints on the way of efficient engineering of anaerobic rumen fungi. By providing this knowledge, this review aims to help research in this field with identifying the challenges that must be addressed by future experiments to achieve the full potentials of these promising microorganisms. To sum up, the pretreatment of lignocelluloses by anaerobic fungi can prevent carbohydrate loss due to respiration (compared to white-rot fungi). Following fungal mixed acid fermentation, the obtained slurry containing sugars and more susceptible holocellulose can be directly consumed by AD microorganisms (bacteria, methanogens). The bioaugmentation of anaerobic fungi into the AD process can increase methane biosynthesis by >3.3 times. Despite this, for the commercial AD process, novel genetic engineering techniques and kits must be developed to efficiently improve anaerobic fungi viability throughout the AD process., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The ever-increasing rise in the global population coupled with rapid urbanization demands considerable consumption of fossil fuel, food, and water. This in turn leads to energy depletion, greenhouse gas emissions and wet wastes generation (including food waste, animal manure, and sewage sludge). Conversion of the wet wastes to bioenergy and biochar is a promising approach to mitigate wastes, emissions and energy depletion, and simultaneously promotes sustainability and circular economy. In this study, various conversion technologies for transformation of wet wastes to bioenergy and biochar, including anaerobic digestion, gasification, incineration, hydrothermal carbonization, hydrothermal liquefaction, slow and fast pyrolysis, are comprehensively reviewed. The technological challenges impeding the widespread adoption of these wet waste conversion technologies are critically examined. Eventually, the study presents insightful recommendations for the technological advancements and wider acceptance of these processes by establishing a hierarchy of factors dictating their performance. These include: i) life-cycle assessment of these conversion technologies with the consideration of reactor design and catalyst utilization from lab to plant level; ii) process intensification by integrating one or more of the wet waste conversion technologies for improved performance and sustainability; and iii) emerging machine learning modeling is a promising strategy to aid the product characterization and optimization of system design for the specific to the bioenergy or biochar application., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

Waste cooking oil (WCO) is a hazardous waste generated at staggering values globally. WCO disposal into various ecosystems, including soil and water, could result in severe environmental consequences. On the other hand, mismanagement of this hazardous waste could also be translated into the loss of resources given its energy content. Hence, finding cost-effective and eco-friendly alternative pathways for simultaneous management and valorization of WCO, such as conversion into biodiesel, has been widely sought. Due to its low toxicity, high biodegradability, renewability, and the possibility of direct use in diesel engines, biodiesel is a promising alternative to mineral diesel. However, the conventional homogeneous or heterogeneous catalysts used in the biodiesel production process, i.e., transesterification, are generally toxic and derived from non-renewable resources. Therefore, to boost the sustainability features of the process, the development of catalysts derived from renewable waste-oriented resources is of significant importance. In light of the above, the present work aims to review and critically discuss the hazardous WCO application for bioenergy production. Moreover, various waste-oriented catalysts used to valorize this waste are presented and discussed., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Aquatic weeds pose hazards to aquatic ecosystems and particularly the aquatic environment in shellfish aquaculture due to its excessive growth covering entire freshwater bodies, leading to environmental pollution particularly eutrophication intensification, water quality depletion and aquatic organism fatality. In this study, pyrolysis of six aquatic weed types (wild and cultured species of Salvinia sp., Lemna sp. and Spirodella sp.) were investigated to evaluate its potential to reduce and convert the weeds into value-added chemicals. The aquatic weeds demonstrated high fixed carbon (8.7-47.3 wt%), volatile matter content (39.0-76.9 wt%), H/C ratio (1.5-2.0) and higher heating value (6.6-18.8 MJ/kg), representing desirable physicochemical properties for conversion into biofuels. Kinetic analysis via Coats-Redfern integral method obtained different orders for chemical reaction mechanisms (n = 1, 1.5, 2, 3), activation energy (55.94-209.41 kJ/mol) and pre-exponential factor (4.08 × 10 4 -4.20 × 10 17 s -1 ) at different reaction zones (zone 1: 150-268 °C, zone 2: 268-409 °C, zone 3: 409-600 °C). The results provide useful information for design and optimization of the pyrolysis reactor and establishment of the process condition to dispose this environmentally harmful species., (Copyright © 2021. Published by Elsevier B.V.)

Improper healthcare waste (HCW) management poses significant risks to the environment, human health, and socio-economic sustainability due to the infectious and hazardous nature of HCW. This research aims at rendering a comprehensive landscape of the body of research on HCW management by (i) mapping the scientific development of HCW research, (ii) identifying the prominent HCW research themes and trends, and (iii) providing a research agenda for HCW management towards a circular economy (CE) transition and sustainable environment. The analysis revealed four dominant HCW research themes: (1) HCW minimization, sustainable management, and policy-making; (2) HCW incineration and its associated environmental impacts; (3) hazardous HCW management practices; and (4) HCW handling and occupational safety and training. The results showed that the healthcare industry, despite its potential to contribute to the CE transition, has been overlooked in the CE discourse due to the single-use mindset of the healthcare industry in the wake of the infectious, toxic, and hazardous nature of HCW streams. The findings shed light on the HCW management domain by uncovering the current status of HCW research, highlighting the existing gaps and challenges, and providing potential avenues for further research towards a CE transition in the healthcare industry and HCW management., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Global environmental awareness has encouraged further research towards biofuel production and consumption. Despite the favorable properties of biofuels, the sustainability of their conventional production pathways from agricultural feedstocks has been questioned. Therefore, the use of non-food feedstocks as a promising approach to ensure sustainable biofuel production is encouraged. However, the use of synthetic solvents/chemicals and energy carriers during biofuel production and the consequent adverse environmental effects are still challenging. On the other hand, biofuel production is also associated with generating large volumes of waste and wastewater. Accordingly, the circular bioeconomy as an innovative approach to ensure complete valorization of feedstocks and generated waste streams under the biorefinery scheme is proposed. In line with that, the current study aims to assess the environmental sustainability of bioethanol production in a safflower-based biorefinery using the life cycle assessment framework. Based on the obtained results, safflower production and its processing into 1 MJ bioethanol under the safflower-based biorefinery led to damage of 2.23E-07 disability-adjusted life years (DALY), 2.35E-02 potentially disappeared fraction (PDF)*m 2 *yr, 4.76E-01 kg CO 2 eq., and 3.82 MJ primary on the human health, ecosystem quality, climate change, and resources, respectively. Moreover, it was revealed that despite adverse environmental effects associated with safflower production and processing, the substitution of conventional products, i.e., products that are the typical products in the market without having environmental criteria, with their bio-counterparts, i.e., products produced in the biorefinery based on environmental criteria could overshadow the unfavorable effects and substantially enhance the overall sustainability of the biorefinery system. The developed safflower-based biorefinery led to seven- and two-time reduction in damage to the ecosystem quality and resources damage categories, respectively. The reductions in damage to human health and climate change were also found to be 52% and 24%, respectively. The weighted environmental impacts of the safflower-based biorefinery decreased by 64% due to the production of bioproducts, mainly biodiesel and biogas, replacing their fossil-based counterparts, i.e., diesel and natural gas, respectively. Finally, although the main focus of the developed safflower-based biorefinery was biofuel production, waste valorization and mainly animal feed played a significant role in improving the associated environmental impacts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Competing Interests: Declaration of interests We declare no competing interests.

A diesel engine running on diesel/biodiesel mixtures containing ethylene glycol diacetate (EGDA) was investigated from the exergoeconomic and exergoenvironmental viewpoints. Biodiesel was mixed with petrodiesel at 5% and 20% volume ratios, and the resultant mixtures were then doped with EGDA at 1-3% volume ratios. The exergetic sustainability indicators of the engine operating on the prepared fuel formulations were determined at varying engine loads. The indicators were selected to support decision-making on fuel composition and engine load following thermodynamic, economic, and environmental considerations. The engine load markedly affected all the studied exergetic parameters. The highest engine exergetic efficiency (39.5%) was obtained for petrodiesel doped with 1 v/v% EGDA at the engine load of 50%. The minimum value of the unit cost of brake power exergy (49.6 US$/GJ) was found for straight petrodiesel at full-load conditions, while the minimum value of the unit environmental impact of brake power exergy (29.9 mPts/GJ) was observed for petrodiesel mixed with 5 v/v% biodiesel at the engine load of 75%. Overall, adding EGDA to fuel mixtures did not favorably influence the outcomes of both exergetic methods due to its energy-intensive and cost-prohibitive production process. In conclusion, although petrodiesel fuel improvers such EGDA used in the present study could properly mitigate pollutant emissions, the adverse effects of such additives on thermodynamic parameters of diesel engines, particularly on exergoeconomic and exergoenvironmental indices, need to be taken into account, and necessary optimizations should be made before their real-world application., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)