MAPP Compatibilized Recycled Woodchips Reinforced Polypropylene Composites with Exceptionally High Strength and Stability
Wood chips were used in their original form without any physical or chemical treatment as reinforcement for polypropylene to develop composites as potential replacement for medium density fiber (MDF) boards, gypsum based false ceiling and other building materials. Wood chips are generated as byproducts and have limited and low value applications. Composites with up to 90% wood chips were developed through compression molding and the mechanical, acoustic and thermal properties were studied. Further, maleated polypropylene (MAPP) was used (1-5% w/w based on woodchips used) as compatibilizer and changes in properties were recorded. Up to 300% increase in tensile properties were observed when 5% compatibilizer was present. Tensile properties of the composites containing MAPP were higher than that of commercially available medium density plywood boards and also gypsum based ceiling tiles. Addition of MAPP did not change thermal conductivity but decreased sound absorption. Wood chips reinforced PP composites containing MAPP show exceedingly high properties and could replace particle, fiber boards and other building materials in current use. Utilizing the wood waste also results in environmentally friendly, sustainable and low cost building materials.
Valorization of Skin Waste for the Synthesis of Angiotensin Converting Enzyme-1 (ACE1) Inhibitory Peptides
One of potential inhibitors which is widely used for the clinical treatment of COVID-19 in comorbid patients is Angiostensin Converting Enzyme-1 (ACE1) inhibitor. A safer peptide-based ACE1 inhibitor derived from salmon skin collagen, that is considered as the by-product of the fish processing industry have been investigated in this study. The inhibitory activity against ACE1 was examined using in vitro and in silico methods. In vitro analysis includes the extraction of acid-soluble collagen, characterization using FTIR, Raman, UV-Vis, XRD, cytotoxicity assay, and determination of inhibition against ACE1. In silico method visualizes binding affinity, molecular interaction, and inhibition type of intact collagen and active peptides derived from collagen against ACE1 using molecular docking. The results of FTIR spectra detected amide functional groups (A, B, I, II, III) and imine proline/hydroxyproline, while the results of Raman displayed peak absorption of amide I, amide III, proline/hydroxyproline ring, phenylalanine, and protein backbone. Furthermore, UV-Vis spectra showed typical collagen absorption at 230 nm and based on XRD data, the chain types in the samples were α-helix. ACE1 inhibition activity was obtained in a concentration-dependent manner where the highest was 82.83% and 85.84% at concentrations of 1000, and 2000 µg/mL, respectively, and showed very low cytotoxicity at the concentration less than 1000 µg/mL. In silico study showed an interaction between ACE1 and collagen outside the active site with the affinity of - 213.89 kcal/mol. Furthermore, the active peptides of collagen displayed greater affinity compared to lisinopril, namely HF (His-Phe), WYT (Trp-Tyr-Thr), and WF (Trp-Phe) of - 11.52; - 10.22; - 9.58 kcal/mol, respectively. The salmon skin-derived collagen demonstrated ACE1 inhibition activity with a non-competitive inhibition mechanism. In contrast, the active peptides were predicted as potent competitive inhibitors against ACE1. This study indicated that valorization of fish by-product can lead to the production of a promising bioactive compound to treat COVID-19 patient with diabetic comorbid.
Antibacterial Ag/Graphene-Integrated
Air pollution and infectious diseases (such as the COVID-19 pandemic) have attracted considerable attention from governments and scientists worldwide to find the best solutions to address these issues. In this study, a new simultaneous antibacterial and particulate matter (PM) filtering Ag/graphene-integrated non-woven polypropylene textile was fabricated by simply immersing the textile into a Ag/graphene-containing solution. The Ag/graphene nanocomposite was prepared by reducing Ag ions on the surface of graphene nanoplatelets (GNPs) using the leaf extract. The prepared Ag/graphene textile was characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), Energy Dispersive X-ray (EDX), and contact angle measurements. The results showed excellent integration of the Ag/GNP nanocomposite into the non-woven polypropylene textile matrix. The prepared textile exhibited superhydrophobicity with a contact angle of 152°. The maximum PM removal percentage of the Ag/GNP-integrated textile was determined to be 98.5% at an Ag/GNP content of 1.5% w/w and a silicon adhesive of 1% w/w. The Ag/GNP textile exhibited high antibacterial activity toward with no sign of bacteria on the surface. Remarkably, the as-prepared Ag/GNP textile was highly durable and stable and could be reused many times after washing.
Transglycosylation of Stevioside by a Commercial β-Glucanase with Fungal Extracted β-Glucans as Donors
Alternative sweeteners, such as steviol glucosides from the plant Bertoni, are becoming increasingly popular for the design of next-generation foodstuffs. However, the bitter aftertaste of native steviol glucosides is one of the main reasons behind consumer reluctance towards stevia-containing products. Biocatalysis could be a sustainable solution to this problem, through addition of glucosyl moieties to the molecule. Glycoside hydrolases are enzymes performing transglycosylation reactions, and they can be exploited for such modifications. In the present work, the commercial β-glucanase Finizym 250L® was employed for the transglycosylation of stevioside. After optimization of several reaction parameters, the maximal reaction yield obtained was 19%, with barley β-glucan as the glycosyl donor. With the aim to develop a sustainable process, β-glucan extracts from different fungal sources were prepared. Pulsed Electric Field pretreatment of mycelial biomass resulted in extracts with higher β-glucan content. The extracts were tested as alternative glucosyl donors, reaching up to 15.5% conversion yield, from -extracted β-glucan. Overall, in the present work a novel enzymatic process for the modification of stevioside is proposed, with concomitant valorization of β-glucans extracted from fungal biomass, potentially generated as a byproduct from other applications, in concert with the principles of circular economy.
Exploring the Potential for Steel Slags Valorisation in an Industrial Symbiosis Perspective at Meso-scale Level
A greater reuse of steel slags would bring considerable benefits both from an environmental and economic point of view. The development of tools and strategies to monitor at different scales resources and waste flows would allow for better resource planning and a more sustainable management on territory. The aim of this study is to investigate and analyse the supply chain that deals with the management of steel slags at meso-level, in order to investigate the state of implementation of industrial symbiosis (IS), its potential and its improvement. A Mass Flow Analysis (MFA) has been implemented, through big data analysis coming from the integration of regional and provincial databases with a careful data processing from questionnaires. This integrated methodology has proved to be a valid tool to monitor the recovery and reuse, the implementation of industrial symbiosis and to plan improvement actions. This paper reports a representation of the current situation regarding the production, recovery and reuse of these materials in production processes for which they are suitable, with a view to their full exploitation, following the principles of circular economy and an analysis of the mutual exchange that occur among steelmaking plants and other business partners in a network of industrial companies. The results showed that most of the steel slags managed at meso-level (Province of Brescia, Italy) is still unfortunately destined for landfill with low percentage of them classified as by-product highlighting as the IS is not adequately applied. Of the slag destined for treatments and recovery processes, almost all of them are Electric Arc Furnace slag, which are mainly reused for hydraulically bound base layers and road sub-bases (about 85% of the total recovered) and as aggregates for the production of cement and bituminous mixes (about 15% of the total recovered). Results shows as further effort should be made in term of policies and strategies to incentivize IS and to increase the recovery.
Sewage Sludge Management at District Level: Reduction and Nutrients Recovery via Hydrothermal Carbonization
In this study, two scenarios of a municipal wastewater treatment plant (WWTP) are presented, which include the integration of the hydrothermal carbonization (HTC) process into the sludge line as a post-treatment of the anaerobic digestion (AD) process. The objective of the simulation is to investigate the performances of AD + HTC treatment to reduce sludge production and improve nutrient and energy recovery. For this purpose, the scheme of an under-construction WWTP was considered, named Trento 3 (Trento, Italy) and with a treatment capacity of 300,000 PE. In the first scenario, the HTC process was fed with thickened sludge from the Trento 3 WWTP, while in the second scenario, dewatered sludge from other local WWTPs was also used as feedstock for the HTC process. Both scenarios allowed to obtain a considerable sludge reduction ranging from 70 to 75% with a notably increase in the biogas production up to 47%, due to the recycling of HTC liquor (HTCL) to the anaerobic digester. Considering nutrients recovery, all the phosphorus and nitrogen present in the HTCL could be used for struvite precipitation with an average yearly gain of 1 million euros. Moreover, the introduction of HTC in the Trento 3 WWTP could allow a reduction in the sludge management costs of up to 2 M€/year.
Natural Antioxidant Extracted Waste Cooking Oil as Sustainable Biolubricant Formulation in Tribological and Rheological Applications
Developing eco-friendly formulations using waste cooking oil as renewable biomass is of great interest and commercial importance in the fuels and lubricant industry. This manuscript reports novel study on preparing a biolubricant formulations as WCO-1, WCO-2 and WCO-3 by blending the curcumin extracted soybean waste cooking oil in three different compositions viz 10%, 20%, 30% v/v with the mineral base oil N-150. Curcumin was extracted as a natural antioxidant in 0.5 wt% waste cooking oil to inhibit thermal oxidation. This study comprises a detailed analysis in terms of tribological, rheological and thermophysical characteristics such as viscosity, viscosity index, pour point and flash point parameters of the biolubricant by standard ASTM methods. Further, tribological and rheological analysis was done by the four-ball wear tester and Anton Paar, MCR-72, respectively. The thermophysical evaluation of WCO formulated biolubricant has shown excellent properties. The viscosity index of the formulated biolubricant increases with an increase in the concentration of waste cooking oil. In contrast, the pour point has also been depressing at lower temperature conditions. Thus, WCO based biolubricant was found to be more effective at extreme temperature conditions than the mineral base oil (N-150). Rheological studies have indicated the non-Newtonian behaviour of the biolubricant with an increase in shear rate. Whereas, tribological analysis demonstrates that wear scar diameter has significantly reduced from 0.685 to 0.573 mm, and the coefficient of friction decreased from 0.117 to 0.080 with respect to the mineral base oil. Thus, a straightforward green approach has been discovered by directly utilizing waste cooking oil for biolubricant formulation.
Effect of Solid-State Fermentation on the Essential Oil Yield of Residues
The solid waste of rhizomes generated after its cold juice process making is mostly unused and discarded even though they can contain essential oil. Conventional techniques such as hydrodistillation can be used to extract essential oil, but this generally results in low essential oil yield and inefficient extraction time. Solid-state fermentation as a pretreatment of distillation could improve the yield of essential oil. In this study, we evaluated the effect of solid state fermentation on the yield of extraction of solid wastes essential oil. The solid-state fermentation was carried out naturally without any addition of inoculum and the extraction was performed by hydrodistillation. Under experimental conditions at room temperature ( ) with a moisture content of 44% and anaerobically in the dark, the treatment of 7 days of solid state fermentation followed by 2 h of hydrodistillation provided the highest yield of 1.21% as compared to non-fermented of 0.35% and of 0.96% relative to the raw plant material representing an increase of 71% and 21% respectively. A set of experiments was then carried out by a Doehlert matrix to optimize the yield of extraction. Two independent variables, namely the distillation time and the fermentation time, were studied. Under optimal experimental conditions of 10 days and 4 h, a yield of 1.96% was obtained validating the statistical model. The solid state fermentation applied before the hydrodistillation step has been successful and proves its potential to improve the efficiency of essential oil extraction.
Environmental Life Cycle Assessment of Hydrothermal Carbonization of Sewage Sludge and Its Products Valorization Pathways
This study is aimed at evaluating through Life Cycle Assessment (LCA) the environmental performances of an integrated system of an existing Water Resources Recovery Facility (WRRF) and a hypothetical hydrothermal carbonization (HTC) plant applied to the generated sewage sludge (SS). Beside the valorisation of the solid product (hydrochar, HC) as a fuel substituting lignite, the possibility to valorize also the liquid fraction (process water, PW) derived by the HTC, by anaerobic digestion to produce biogas, is here proposed and analysed. Additionally, phosphorus recovery from HC, prior its use, by acid leaching with nitric acid is also suggested and evaluated. Thus, four integrated scenarios, based on SS carbonization, are proposed and compared with the current SS treatment, based on composting outside of the WRRF (Benchmark scenario). The proposed scenarios, based on HTC, show improved performances with respect to the benchmark one, for thirteen of sixteen considered impact indicators. For the Climate Change (CC) indicator, the two HTC scenarios are able to reduce the impacts up to - 98%, with respect to the Benchmark. Further, the introduction of anaerobic digestion of PW proves to reduce impacts more than other configurations in eleven on sixteen impact categories. On the contrary, the introduction of phosphorus recovery process negatively affects the values for most of indicators. Thus, possible solutions to improve the integration of this process are outlined (e.g., the use of sulfuric acid instead of nitric one, or the application of a different ratio between solid and acidified solution during acid leaching of HC to recover phosphorus).
Recent Progresses in Eco-Friendly Fabrication and Applications of Sustainable Aerogels from Various Waste Materials
Tons of waste from residential, commercial and manufacturing activities are generated due to the growing population, urbanization and economic development, prompting the need for sustainable measures. Numerous ways of converting waste to aerogels, a novel class of ultra-light and ultra-porous materials, have been researched to tackle the issues of waste. This review provides an overview of the status of aerogels made from agricultural waste, municipal solid, and industrial waste focusing on the fabrication, properties, and applications of such aerogels. The review first introduced common methods to synthesize the aerogels from waste, including dispersion and drying techniques. Following that, numerous works related to aerogels from waste are summarized and compared, mainly focusing on the sustainability aspect of the processes involved and their contributions for environmental applications such as thermal insulation and oil absorption. Next, advantages, and disadvantages of the current approaches are analyzed. Finally, some prospective waste aerogels and its applications are proposed.
Effects of Chlorides and Sulphates on Heavy Metal Leaching from Mortar with Raw and Electrodialytically Treated MSWI Fly Ash
Municipal solid waste incineration (MSWI) fly ash could be used as supplementary cementitious material in cement-based materials. However, heavy metal leaching, such as Cd, Cr, Cu, Pb and Zn, both from the MSWI fly ash and cement-based materials containing MSWI fly ash, remains a persistent obstacle. Here, an up-scaled electrodialytic treatment was used as a pre-treatment to remove heavy metals from MSWI fly ash before using the fly ash in mortar. Mortar samples with 10 wt% replacement of cement with either raw or elecrtodialytically treated MSWI fly ash were subjected to monolithic (in-use scenario) and crushed mortar (end-of-life scenario) leaching tests. The environmental conditions (e.g., exposure to chlorides or sulfates) at the surface of cement-based materials can affect leaching. Acidified HO, NaCl or NaSO solutions were, therefore, used for the leaching tests. Up to 80% heavy metal removal by the up-scaled electrodialytic pre-treatment was feasible. Regulatory limits for disposing of the MSWI fly ash in non-hazardous waste landfills were exceeded, even if the electrodialytic treatment removed heavy metals. However, leaching from monolithic mortar samples complied with the regulatory limits, while Cr leaching exceeded the regulatory limits for all crushed mortar samples when using NaCl or NaSO. Both NaCl and NaSO generally increased the heavy metal leaching yield from fly ash and mortar compared to leaching with acidified HO. The results of the study suggest that environmental conditions should be taken into account when assessing leaching from cement-based materials with MSWI fly ash.
Major Phytochemical Compounds, In Vitro Antioxidant, Antibacterial, and Antifungal Activities of Six Aqueous and Organic Extracts of L. Flower Waste
After being considered as a neglected product, agricultural waste is nowadays considered of paramount importance. It has become a source of many chemical compounds with industrial, pharmaceutical, and food applications. This study aims to evaluate the primary phytochemical content, the antioxidant properties, and the antimicrobial activities of different extracts of saffron flower waste (SFE) against bacterial and fungal strains involved in diverse pathologies in southern Morocco.
Commercial Initiation of Feather Hydrolysate as Supreme Fertilizer: A Smart Bio-Cleaning Strategy of Poultry Waste
Economic development of India mainly depends on agricultural sectors. The Indian traditional agricultural system is mainly based on chemical fertilizer to get better yield. The main motto of this research work is to change the traditional faith of Indian farmers and rural Indian economy.
Characterisation and Antibacterial Properties of Novel Biodegradable Films Based on Alginate and Roselle ( L.) Extract
Composite films were prepared with alginate and roselle extract (HE) at different concentrations (1%, 3%, and 5% w/v) via solvent casting technique and analyzed in terms of physical, mechanical, and antibacterial properties. The incorporation of HE into alginate films resulted in rough and heterogeneous surface characteristics with increasing concentrations of HE. The thickness and water vapor permeability of alginate-HE composite films were significantly higher ( < 0.05) compared to pure alginate films. Moreover, water content, solubility, swelling, tensile strength, and elongation at break value of the composite films decreased ( < 0.05) with increasing concentrations of the extract. FTIR spectra revealed shifts and intensity variations in the composite films and the formation of new peaks suggesting a possible interaction between alginate and HE. Alginate-HE films exhibited good antibacterial activity against Gram-positive ( and ) and Gram-negative ( and ) bacteria. The antibacterial effect of the films, more pronounced against Gram-positive bacteria, increased with higher amounts of HE. The resulting films may be utilised as new biodegradable, antibacterial films in the food packaging industry to prolong shelf life and preserve food safety.
Stems a New Sustainable Source for Cellulosic Materials: Production and Characterization of Cellulose Microfibers and Nanocrystals
In this study, stem waste was identified, for the first time, as a potential natural source to produce cellulose microfibers (CMF), as well as cellulose nanocrystals (CNC) with unique functionalities by using various organic acids. The CMF extraction was carried out using alkali and bleaching treatments, while the CNC were isolated under acid hydrolysis by using sulfuric acid (S-CNC), phosphoric acid (P-CNC), and hydrochloric acid / citric acid mixture (C-CNC). The CMF and CNC physicochemical, structural, morphological, dimensional, and thermal properties were characterized. CMF with a yield of 53%, diameter of 5 to 30 µm and crystallinity of 57% were successfully obtained. In contrast, CNC showed a rod-like shape with an aspect ratio of 53, 95, and 64 and a crystallinity index of 84, 79, and 72% for S-CNC, P-CNC, and C-CNC, respectively. Results suggested that the type of acid significantly influenced the structure, morphology, and thermal stability of CNCs. Based on these results, stem waste is a great candidate source for cellulose derivatives with excellent characteristics.
Triple Bottom-Line Evaluation of the Production of Animal Feed from Food Waste: A Life Cycle Assessment
This study applies a triple bottom line (TBL) framework that incorporates the environmental, economic, and social impacts of producing animal feed from food waste (FW) collected at the post-consumption stage of the food supply chain. The environmental bottom line (BL) is conducted using life cycle assessment (LCA), the economic BL is calculated using the net present value (NPV), while the social BL is assessed using the strengths, weaknesses, opportunities, and threats (SWOT) analysis. The results within the environmental BL indicate that at a 13.8% recovery rate, animal feed produced from a ton of FW saves 0.33 m equivalent of crop land but requires 3.5 tons of water compared to 0.9 tons and 0.78 tons for landfilling and incineration for FW treatment respectively. In addition, the production of animal feed from one ton of FW emits 1064.6 kg CO-eq, compared to 823.6 kg CO-eq using landfilling and 781.9 kg CO-eq when incinerated. The economic BL indicates a profit of $3.65/ton from incinerating FW, compared to cost of $93.8 and $137.6 per ton for animal feed production and landfilling of FW respectively. The analytic hierarchy process (AHP) is applied to integrate the TBL scores and rank the scenarios accordingly. AHP recommends animal feed and incineration over landfilling by a fourfold higher score. A simulation using an augmented simplex lattice mixture (ASLM) design recommends incineration with energy recovery over animal feed production from FW collected at the consumer stage. Sensitivity analysis indicates that the production of animal feed from FW is environmentally feasible if the safe recovery rate exceeds 48%, is which possible for FW collected at early stages of the food supply chain.
Bio-scouring of Non-spinnable Cotton by a Crude Enzyme of a New Fungal Strain sp. VM-1, Isolated from Banana Pseudostem Waste
In the present study, we isolated and identified a new fungus, sp VM-1 from banana pseudostem waste. The fungal strain, sp. VM-1 was grown on a substrate (banana pseudostem, cottonseed hulls and cottonseed meal in the ratio of 60:30:10, respectively) for 7 days and the crude enzyme was extracted from the fermented substrate. The pectinase activity in crude enzyme extract was 551 (U/ml). The crude enzyme extracted from sp. VM-1 was evaluated for bio-scouring of non-spinnable cotton. The non-spinnable cotton taken in the study was short staple cotton (SSC), cotton linters (CL) and non-woven cotton fabric (NWCF). The maximum absorbency (2 s) in non-spinnable cotton was achieved under optimized process conditions: enzyme extract level (40%), temperature (40 ± 2 °C) and time (40 min). The quality parameters of bio-scoured cotton meet the Indian Pharmacopoeia (IP) standards. A solid state fermenter was designed to scale-up the crude enzyme production up to 30 l. This is the first report on bio-scouring of under-utilized short cotton fibres at lower temperature (40 ± 2 °C). The present study offers a simple and eco-friendly bio-scouring process as an alternative to toxic chemical scouring of under-utilized short staple cotton fibres.
Valorization and Development of Acorn Starch as Sustainable and High-Performance Papermaking Additive for Improving Bagasse Pulp and Paper Properties
Improving bagasse pulp and paper properties using forest-byproduct biomass, native Acorn starch (NAS), was compared with conventional wet-end additive cationic corn starch (CCS). The extracted acorn starch was characterized by SEM, XRD, and GPC. The results clearly showed irregular granular shape (6-12 μm) with rough surfaces, C-type XRD pattern, and 436.2 kDa molecular weights for NAS. The bagasse pulp retention and drainage as keys of operation performance and runnability were superior by NAS in comparison with CCS, while the lowest dosage of NAS (0.5%) showed superior results than the highest dosages of CCS (1% & 1.5%). The higher NAS adsorption onto the fiber surfaces compared to CCS could be concluded by higher water retention value (WRV) of the pulp together with higher density (up to 20%) and mechanical properties of the produced paper, e.g., tensile (up to 63%), burst (up to 37%) and tear (up to 11%) indices. NAS exploiting naturally as a papermaking additive would provide performance higher than commercial chemically-modified starch.
A Review of Graphene: Material Synthesis from Biomass Sources
Single-atom-thick graphene is a particularly interesting material in basic research and applications owing to its remarkable electronic, mechanical, chemical, thermal, and optical properties. This leads to its potential use in a multitude of applications for improved energy storage (capacitors, batteries, and fuel cells), energy generation, biomedical, sensors or even as an advanced membrane material for separations. This paper provided an overview of research in graphene, in the area of synthesis from various sources specially from biomass, advanced characterization techniques, properties, and application. Finally, some challenges and future perspectives of graphene are also discussed.
A Comparative Study of Effects of Biodegradable and Non-biodegradable Microplastics on the Growth and Development of Black Soldier Fly Larvae ()
This study aimed to investigate the digestion process of biodegradable and non-biodegradable microplastics (MPs) within black soldier fly larvae (BSFL) and assess their impact on larval growth and development. The goal was to understand the fate of MPs within BSFL, considering their potential for waste conversion polluted with MPs.