Waste Products Research Articles

Hybrid Pectin-Fibroin Microgels with Supramolecular and Covalent Cross-Links.

Sugar beet pectin, an anionic polysaccharide, and silk fibroin, a high molecular weight protein, undergo gelation through ionic interactions and conformational changes, leading to hydrogel formation. Although many studies have focused on bulk gel systems involving polysaccharides and proteins, more research is needed to investigate their properties at the microscale level. In this context, we have developed a microgel system based on a pectin/fibroin combination and investigated its properties. We focused on two gelation mechanisms: physical cross-linking and enzymatic covalent cross-linking. The pectin/fibroin microgels were fabricated using droplet-based microfluidics, and the secondary structure, mechanical properties, and degradation profiles were investigated. Our experimental results show that the microgels exhibit an ordered β-sheet structure, a Young's modulus in the range of 10 to 20 kPa, and that degradation can be promoted using protease enzymes. Finally, the biocompatibility of the microgels is assessed using the Alamar Blue cell viability assay with human pulmonary fibroblasts (HPFs). This research presents a highly functional hybrid biomaterial produced from waste products and a structural protein, demonstrating its cell compatibility and potential in tissue engineering applications.

Valorizing Bio-Waste and Residuals.

The circular bioeconomy connects waste recycling with utilizing organic biomass waste for bioenergy, bio-based materials, and biochemical production. This integration promotes efficient resource utilization, reduced greenhouse gas emissions, and sustainable economic growth. Several technologies such as composting, anaerobic digestion, biochar production, gasification, pyrolysis, pelletization, and advanced thermal conversion technologies are utilized to manage agricultural waste efficiently. Waste-to-energy systems and food waste valorization techniques are employed to convert agro-waste into renewable energy sources such as bioethanol, biodiesel, and biogas through fermentation, transesterification, and anaerobic digestion. These biofuels offer renewable alternatives to fossil fuels, reducing greenhouse gas emissions and dependence on non-renewable resources. Rice husk, a globally abundant agricultural waste, can be utilized for energy production through technologies like direct combustion and fast pyrolysis. Biobutanol, synthesized from acetone-butanol-ethanol fermentation of agricultural residues like orange peel, presents a promising fuel option. Agricultural waste can also serve as feedstock for bio-based chemicals like organic acids, solvents, and polymers, reducing reliance on petroleum-based chemicals. Agro-waste materials like grass, garlic peel, and rice bran have shown potential for dye adsorption in wastewater treatment applications. Moreover, agricultural waste can be repurposed as animal feed, contributing to waste reduction and providing sustainable nutrition for livestock. Plant seeds and green biomass offer sustainable protein sources, while residues like straw and sawdust can be used for mushroom cultivation. Agro-waste biopolymers like starch and cellulose can be transformed into biodegradable plastics and biocomposites, offering eco-friendly alternatives. Additionally, agro-waste materials like straw, rice husks, and bamboo can be processed into construction materials, reducing environmental impact in building projects. Extracts from plant residues and fruit pomace can be utilized in pharmaceuticals, nutraceuticals, and cosmetics. Valorizing agro-waste for food, feed, fibers, and fuel offers opportunities to minimize waste and maximize resource efficiency, resulting in high-value products.

Synthesis of Benzoisochromene Derivatives via C-H Activation-Initiated Cascade Formal [4+2] and [2+4] Annulation of Aryl Enaminone with Vinyl-1,3-dioxolan-2-one.

Cascade annulation reactions can assemble structurally intricate polycyclic molecules from simple starting materials with enhanced efficiency and minimized production of waste. Presented herein is a concise and effective synthesis of benzoisochromene derivatives based on a C-H activation-initiated cascade formal [4+2]/[2+4] annulation of aryl enaminone with vinyl-1,3-dioxolan-2-one. In constructing the six-membered carbocycle, aryl enaminone acted as the C4 synthon while vinyl-1,3-dioxolan-2-one acted as the C2 synthon. In constructing the six-membered O-heterocycle, on the other hand, the former acted as C2 synthon while the latter acted as C3O1 synthon. To our knowledge, this is the first simultaneous construction of both a carbocycle and an O-heterocycle via concurrent C-H/C-N/C-O bond cleavage and C-C/C-C/C-O bond formation. In general, this novel protocol features the use of readily obtainable substrates of broad scope, excellent atom- and step-economy, intriguing reaction pathway, and valuable products.

Hepatic damage in residents of a major coal mining region in Brazil

Coal mining and the subsequent burning of coal release waste products that can accumulate in the environment and pose a threat to human health. Therefore, this study aims to evaluate hepatic damage by bilirubin, ALP, ALT, and GGT among men from the largest coal mining region of Brazil. A cross-sectional study was conducted in seven municipalities in Brazil's largest coal mining region. Participants were male individuals (n = 320) residing in these municipalities, with varying degrees of exposure to coal mining activities. Socioeconomic, demographic, lifestyle, and health information were collected, along with blood samples for measuring liver function markers: bilirubin, alkaline phosphatase, alanine aminotransferase, and gamma-glutamyltransferase. Despite the population's average liver function markers falling within the reference range, approximately half of the participants exhibited signs of altered liver function. The municipality at the center of coal mining activities showed the highest levels of liver function markers (except for gamma-glutamyltransferase), with nearly half of its residents exhibiting evidence of liver damage. Socioeconomic status and mate consumption were found to be significantly inversely correlated with liver damage. Additionally, individuals who smoked had a significantly higher risk of developing liver problems. These findings underscore the need for comprehensive strategies to address the health impacts of environmental pollutants associated with coal mining. Preventive measures and regulatory policies are crucial to protect public health in regions affected by this industry.

Trends and Challenges in Electrifying Technical Organic Synthesis

AbstractOrganic electrosynthesis is a potential enabler for the energy and resource transition in the chemical industry as it offers a sustainable alternative to homogeneous or heterogeneous processes for producing fine and commodity chemicals. It utilizes electricity instead of hazardous reagents and, thus, also allows reducing the product's carbon footprint and waste production. It enables dynamic operation and safe operation due to galvanostatic process control. Electro‐organic processes are not yet widespread. Engineering tools have not yet been tailored to electro‐organic processes, and more quantitative and model‐based insight is needed. Extensive adoption in the industry requires also efforts regarding electrode material performance and stability, scalable reactor design, and process digitization. Addressing these issues requires interdisciplinary collaboration, particularly between chemists and engineers, to accelerate process implementation with high efficiency and economic feasibility.

Bicomponent Split Microfiber Reusable Textile Products to Achieve a Hygienically Clean Healthcare Setting with a More Sustainable Environmental Footprint

Background: Bicomponent split microfiber reusable wipers and flat mops are innovative textiles used to hygienically clean healthcare surfaces and, hence, reduce hospital-acquired infections. Sustainability improvements are reflected as reduced energy and mass requirements over a life cycle. Methods: The environmental impacts of reusables were compared to disposable equivalents using standard life cycle assessment procedures. Results: With information from 80 hospitals, disposable flat mops and wipers were used at a higher rate than reusable counterparts; the disposable/reusable ratio was 2.3:1 for wipers and 2.5:1 for flat mop pads. Bicomponent split microfiber reusable products had lower impacts (65–95%) in all categories considered: global warming potential, natural resource energy, blue water use, and solid waste production. Discussion: Results reinforce other studies that compare reusable and disposable textile options in healthcare. Laundry energy is an important driver of energy use for reusables. The energy associated with water consumption for disposables’ supply chains is significantly greater than net water consumption for reusables laundry. Conclusions: Selecting disposables versus bicomponent split microfiber reusable flat mops and wipers increases these specific environmental life cycle assessment (LCA) impacts by 320% to 2000%, which is clearly not an environmental sustainability improvement. Group Purchasing Organizations may be barriers to hospital adoption of these reusables.

Metabolomics strategy for diagnosing urinary tract infections

Metabolomics has emerged as a mainstream approach for investigating complex metabolic phenotypes but has yet to be integrated into routine clinical diagnostics. Metabolomics-based diagnosis of urinary tract infections (UTIs) is a logical application of this technology since microbial waste products are concentrated in the bladder and thus could be suitable markers of infection. We conducted an untargeted metabolomics screen of clinical specimens from patients with suspected UTIs and identified two metabolites, agmatine, and N6-methyladenine, that are predictive of culture-positive samples. We developed a 3.2-min LC-MS assay to quantify these metabolites and showed that agmatine and N6-methyladenine correctly identify UTIs caused by 13 Enterobacterales species and 3 non-Enterobacterales species, accounting for over 90% of infections (agmatine AUC > 0.95; N6-methyladenine AUC > 0.89). These markers were robust predictors across two blinded cohorts totaling 1629 patient samples. These findings demonstrate the potential utility of metabolomics in clinical diagnostics for rapidly detecting UTIs.

Legislation of the Russian Federation and the Republic of Belarus in the Field of Waste Management: Comparative Legal Aspects

An urgent area of interstate cooperation between the Russian Federation and the Republic of Belarus is integration projects implemented within the framework of the Union State, focused on environmental protection and rational use of natural resources. The field of waste management of production and consumption belongs to the trend areas of modern state environmental policy. The harmonization of waste legislation contributes to the achievement of strategic goals and the implementation of correlated tasks in the field of waste management in the Russian Federation and the Republic of Belarus.The article highlights the main strategic planning documents in the field of production and consumption waste management in the Russian Federation and the Republic of Belarus. The analysis of the main legal concepts in the field of waste management, such as: «waste», «waste of production and consumption», «waste of production», «waste of consumption», «waste management», provided for by Russian and Belarusian legislation. The features of the conceptual apparatus affecting the legal regulation of relations in the field of waste management are highlighted.

Green technology innovation and waste management: On the role of national governance.

Green technology innovation and waste management: On the role of national governance.

Effect of particle characteristics on granular friction evaluated by dual-slip-plane friction tests

The frictional properties of natural granular materials are important for understanding dynamic natural phenomena such as earthquakes and landslides. The coefficient of friction for natural granular materials varies significantly based on parameters including sliding velocity, normal stress, and experimental conditions (temperature, humidity, etc.). This variation makes it difficult to accurately assess the relative slip resistance of two granular materials under identical conditions. To address this issue, we present a novel experimental approach employing a rotary shear apparatus that applies shear stress to two samples simultaneously. In this study, we utilized this method to determine the slip resistance of 50 different granular materials selected through a tournament competition. Qualitative evaluation results showed that crushed oyster shells, composed of biogenic calcite, were the most slip-resistant material. It was also found that the highly ranked, slip-resistant materials are those with higher peak frictions. Factors contributing to higher friction differed significantly between natural and artificially crushed particles, with the peak friction for crushed particles being strongly influenced by angularity, flatness, specific surface area, and particle-size distribution. The significantly higher friction of crushed oyster-shell particles can be attributed to their composition, which includes particles of various angular shapes, such as needle-like and flat forms. The shape characteristics prevent particle rotation, increasing the number of contact surfaces with neighboring particles. Oyster shells are a cause for concern as an industrial waste product, but their high frictional force has a potential for secondary use as a soil conditioner and slip-resistant material.

Isolation, Screening and Identification of Biopolymer Producing Bacillus cereus from Vegetable Wastes

Plastic materials are causing tremendous damage to the environment. To mitigate the use of synthetic plastics, eco-friendly biopolymers have emerged as an alternative to plastics. Biodegradable plastics such as polyhydroxy butyrate (PHB) are currently used in several synthetic applications similar to biopolymers. The present research was conducted to screen bacteria from vegetable wastes for PHB production. The PHB producing bacteria were screened using Sudan Black-B stain followed by microscopic examination for presence of PHB granules. The PHB was produced through a shake flask fermentation method. The significant PHB-producing bacteria was sequenced by 16S rRNA sequencing (1200bp) (NCIMRef: 2023/Seq-160), by NCIM, Pune, India. The sequencing report showed that the bacterial isolate has 99.93% closest homology to Bacillus cereus. Further, we have deposited this sequence in GenBank (SUB14283541 907R_Seq160_CB4 PP422177, SUB14283541 907R_Seq160_CB4_RC PP422178, SUB14283541 704F_Seq160_CB4 PP422179, and SUB14283541 907RC_704F_Seq160_CB4 PP422180) for further reference and studies. The Bacillus cereus CB 4-derived biopolymer precipitated with acetone has shown maximum PHB yield of 2.7 gL-1. Further research prospects would focus on the optimization of biopolymer production and its quality testing on various parameters.

Design professionals’ awareness and engagement in design for adaptability (DfA) practices

Purpose Design issues are one of the factors contributing to waste production in the Ghanaian construction industry (GCI). Design for adaptability (DfA) is a construction approach that provides buildings with adaptive capabilities during the design phase. It facilitates easy modification, with no or limited demolition, waste reduction, sustainable construction and circularity. However, as to whether design professionals operating in the GCI are aware of this concept and its benefits and whether they consider some of its practices in the designs they produce are something that is yet to be ascertained. Therefore, this study aims to investigate the awareness and engagement of DfA practices among design professionals in the GCI. Design/methodology/approach The study adopted a quantitative research approach to retrieve responses from 236 design professionals (i.e. architects and civil/structural engineers) via survey questionnaires. The data retrieved from the respondents were analyzed using both descriptive and inferential statistical tests. Findings The findings revealed that the design professionals were moderately aware of the concept of DfA. Notwithstanding this moderate level of awareness, the design professionals’ frequency of engagement in DfA practices was high, and factors such as profession, experience and type of firms they worked in, among others, did not influence their level of engagement in DfA practices. Originality/value This study pioneers research on DfA implementation in the GCI. It highlights design professionals’ awareness and engagement in adaptability practices, thereby revealing gaps in knowledge, encouraging sustainable design and promoting resilience in architecture, which could ultimately contribute to a future-proofing built environment in Ghana.

Experimental ‘in-Vitro’ investigation on bio-chemical constituents, radical scavenging activity, and reducing power assay of cow urine

Abstract Cow urine (CU) – a natural bio-organic waste product with immense medicinal value has been traditionally used by human beings for centuries. Researchers have reported the multi-purpose usage of CU in various sectors such as agriculture, medical, emulsified diesel fuel, and electricity generation. The beneficial effect of CU is mainly attributed to its composition which depends on multiple factors such as dietary habit, demography, breed type etc. The CU consists of many useful elements and enzymes which are essential for maintaining the ecological balance and well-being of human society. In spite of its limited benefits, there is still a lack of knowledge on the scientific usage of CU. In this investigation, antioxidant, scavenging activity, and reducing power assay of CU from adult, pregnant, lactating cow and its calf are assessed. The quantity of bio-chemical constituents in CU of adult, pregnant, lactating cow, and calf varied significantly. The concentration of urea, urea nitrogen, uric acid, calcium and creatinine was high in pregnant CU raw sample. Whereas, the amount of sodium and chlorine were high in lactating CU sample. Total phenol concentration was found to be high in adult CU raw sample, followed by calf and pregnant CU raw samples, which is responsible for the antimicrobial activity. Results show highest potent antioxidant activity on the inhibition of DPPH, superoxide anion, nitric oxide, hydroxyl free radicals, and better reducing ability in lactating CU raw sample as compared to other CU samples. In general, the raw CU sample showed better radical scavenging activity whereas distilled CU samples have better Fe3+ reducing power assay.

Correction: Tham et al. Correction: Tham et al. Recovery of Protein from Dairy Milk Waste Product Using Alcohol-Salt Liquid Biphasic Flotation. Processes 2019, 7, 875. Processes 2020, 8, 381

Following publication, concerns were raised to the editorial office relating to a potential conflict of interest between an author and the Academic Editor who supervised the peer-review of this article [...]

Solid Wastes from Geothermal Energy Production and Implications for Direct Lithium Extraction

Direct lithium extraction (DLE) of brines after geothermal power production offers opportunities to produce environmentally benign “green” lithium; however, some environmental impact is inevitable. We examined solid waste production at geothermal power plants in southern California that are also locations for planned DLE facilities. Currently, the geothermal plants in this region produce approximately 79,800 metric tons (wet weight) per year of solid waste, which represents about 28 metric tons per GWh of net electricity production or approximately 500 mg solids per kg geothermal brine. Approximately 15% of this waste requires management as hazardous waste. Solids produced during power production represent about 0.2% of the total dissolved solids in the brine. Lithium production will require the removal of silica, iron, and other metals as part of the DLE process. Using a mass balance approach, we calculate that precipitation of silica and metals could produce up to an additional 6800 mg solids per kg brine. Calcium occurs at very high concentrations, and the amount of solids disposed in landfills will be dependent on the amount of calcium removed during lithium recovery. Our analysis shows that evaluation of brine chemistry in the context of the DLE process is useful for evaluating the potential solid waste impacts of producing lithium from brines.

Effects of Dietary Inclusion of Avocado Seeds on Performance, Nutrient Digestibility, Plasma Biochemical Profile, and Carcass and Meat Traits of Growing Pigs

Avocado seeds (which are discarded during fruit processing) generate residue that could be utilized in pig feeding. The objective of this study was to test the effects of dietary inclusion of dried-milled avocado seeds (DAS) on pig performance, nutrient and energy digestibility, plasma biochemical parameters, and carcass and meat traits. Twenty-four Landrace × Large White barrows (24 kg body weight, BW) were randomly allocated to three experimental treatments: control diet (CO; 18% CP, 1.12% Lys, and 14 MJ ME/kg), and two diets in which 100 or 200 g DAS/kg partially replaced a CO diet (S10 and S20, respectively). Pigs were individually housed (22 ± 1 °C), and feed and water were provided ad libitum. Animals were weighed weekly and individual intake was monitored daily. The total tract apparent digestibility (TTAD) and nitrogen balance were determined. The experiment ended at 40 kg BW, when the animals were slaughtered for blood and tissue sampling. Voluntary feed intake was not affected by the addition of up to 200 g DAS/kg to the diet. However, growth, nutrient TTAD, and nitrogen retention were depressed at the highest DAS inclusion level. The nutritional characteristics of longissimus lumborum muscle were not affected by DAS ingestion. The inclusion of up to 100 g DAS/kg in the diets of growing pigs could be used to add value to this waste product.

Extraction of collagen from the vitreous humor of yellowfin tuna (Thunnus albacares) by pepsin-based protein solubilization

Collagen is a protein of high nutritional value; currently obtaining collagen from fishery discards helps to alleviate the global production of waste. Therefore, the objective of this study was to extract collagen from the eye of yellowfin tuna (Thunnus albacares) by pepsin-based protein solubilization. To this end, the hydroxyproline concentration, solubility, protein composition, and amino acid profile of the collagen were determined. The specimens were selected to weigh between 40 and 60 lbs. The eyes were removed and solubilized using three concentrations of pepsin (6%, 8%, and 10%), then incubated for 48 hours at 18 °C. The 10% pepsin treatment exhibited the highest solubility (92.7% ± 0.15), surpassing the other treatments (91.9% ± 0.25 using 8% pepsin and 91.6% ± 0.45 using 6% pepsin). However, the hydroxyproline concentration was higher in the 8% pepsin treatment (2.62 mg/g ± 0.62), and concurrently, the percentage of collagen was 19.5% ± 4.59. In terms of proximal composition, the 6% pepsin treatment yielded a higher protein percentage than the other treatments (4.05% ± 0.03). The amino acid profile demonstrated the presence of essential amino acids. These findings suggest that discarded fishery by-products may be utilized to obtain collagen, a valuable protein for food industries.

Valorisation of Industrial Waste for Second-Generation Ethanol Production: Towards the Scale-Up of High-Solids Paper Sludge Fermentation

Abstract The scalability of high-solids paper sludge (PS) fermentation was assessed in a 50 L pilot-scale horizontal, solid-state bioreactor using three industrial strains of S. cerevisiae, two of which were engineered to ferment xylose to ethanol and secrete cellulase that would decrease costly exogenous enzyme supplementation. An ethanol titre of 86.2 g/L was achieved with virgin pulp PS (VP-PS) at a solids loading and enzyme dosage of 40% (w/w) and 10 filter paper units (FPU)/g dry PS, respectively, using Ethanol Red®. Enzyme dosages could be decreased to 3.5 FPU/g dry PS at 30% (w/w) solids using Cellusec® 2.0 and Cellusec® 3.3, achieving ethanol yields of 16.5 (81.5% of theoretical maximum) and 15.1 g/100 g dry PS, respectively, due to xylose consumption and cellulase secretion. The study proved an important first step in the potential industrialisation of PS to ethanol, providing suitable operating conditions to reach economically feasible ethanol concentrations > 40 g/L.

Novel roles of ammonia in physiology and cancer.

Ammonia, traditionally recognized as a toxic nitrogen waste product, has recently emerged as a significant player in diverse physiological processes and implicated in cancer biology. This review article provides an overview of the multifaceted impact of ammonia on cellular signaling pathways, energy metabolism, and tumor microenvironment dynamics, in particular its novel roles in neurotransmission, metabolic homeostasis, cancer cell proliferation, and immune modulation. Notably, ammonia accumulates within the tumor microenvironment, promoting non-essential amino acid synthesis, stimulating mTORC1 activation, promoting lipid synthesis, and impairing various immune cell functions, thereby promoting tumor progression. Furthermore, the potential dual role of ammonia as tumorigenic factor and cancer therapeutic target are discussed, shedding light on its complex regulatory mechanisms and clinical implications. This timely review aims to deepen our understanding of the emerging physiological and pathological roles of ammonia, offering valuable insights into its significance as a potential target for diagnostic and therapeutic interventions in cancer and beyond.

Date Seed–Added Biodegradable Films and Coatings for Active Food Packaging Applications: A Review

ABSTRACTThis review examines the incorporation of date seeds, often regarded as a neglected waste product, into food packaging composites, highlighting their potential to enhance sustainability and functionality. Date seeds are abundant in insoluble fibres including cellulose, hemicellulose and lignin, which contribute to their hydrophobic properties and play a crucial role in improving the mechanical strength and moisture barrier capabilities of the composites. Additionally, they are rich in bioactive compounds, including polyphenols and flavonoids, which contribute to their potent antioxidant and antimicrobial activities. These properties extend the shelf life of food products and enhance food safety. The review explores various physicochemical properties, revealing a balance between transparency and UV protection. Furthermore, it discusses the impact of date seeds on water solubility and swelling properties, emphasizing the influence of treatment methods and incorporation levels. Preliminary findings demonstrate the effectiveness of these composites in preserving various food models. However, further research is needed to optimize formulations and functional properties and evaluate sensory acceptability. Overall, the utilization of date seeds presents a promising avenue for developing innovative, eco‐friendly food packaging solutions that align with consumer needs and sustainability goals.