Search Results (372)

The threat of antimicrobial resistance (AMR) and the need for sustainable disinfectants have spurred interest in natural antimicrobials such as essential oils (EOs). However, their application is limited by volatility, poor water solubility, and cytotoxicity. Herein, we present the development of bio-based core–shell sub-micro-/nanocapsules (NCs) with encapsulated oregano (OO), thyme (TO), eucalyptus (EuO), and tea tree (TTO) oils to enhance antimicrobial (AM) performance and reduce cytotoxicity. NCs were synthesized via a nanoencapsulation method using chemically modified zein or poly(methyl vinyl ether-co-maleic anhydride) (GZA) as shell polymers, with selected EOs encapsulated in their core (encapsulation efficacy > 98%). Chemical modification of zein with vanillin (VA) and GZA with either dodecyl amine (DDA) or 3-(glycidyloxypropyl)trimethoxysilane (EPTMS) resulted in improvement in particle size distributions, polydispersity indices (PDIs) of synthesized NCs, and in the stability of the NC-dispersions in water. Antibacterial testing against Staphylococcus aureus and cytotoxicity assays showed that encapsulation significantly reduced toxicity while preserving their antibacterial activity. Among the formulations, GZA-based NCs modified with EPTMS provided the best balance between safety and efficacy. Despite this, life cycle assessment revealed that zein-based NCs were more environmentally sustainable due to lower energy use and material impact. Overall, the approach offers a promising strategy for developing sustainable, effective, and safe EO-based antibacterial agents for AM applications. Full article

Bio-based fertilisers (BBFs) derived from waste streams represent a transformative approach to sustainable agriculture, addressing the dual challenges of waste management and food security. This comprehensive review examines recent advances in BBF production technologies, nutrient recovery mechanisms, soil health impacts, and the benefits of a circular economy. This review, based on an analysis of peer-reviewed studies, demonstrates that BBFs consistently improve the physical, chemical, and biological properties of soil while reducing environmental impacts by 15–45% compared to synthetic alternatives. Advanced biological treatment technologies, including anaerobic digestion, vermicomposting, and biochar production, achieve nutrient recovery efficiencies of 60–95% in diverse waste streams. Market analysis reveals a rapidly expanding sector projected to grow from $2.53 billion (2024) to $6.3 billion by 2032, driven by regulatory support and circular economy policies. Critical research gaps remain in standardisation, long-term performance evaluation, and integration with precision agriculture systems. Future developments should focus on AI-driven optimisation, climate-adaptive formulations, and nanobioconjugate technologies. Full article

Agriculture faces increasing challenges in ensuring food security under a changing climate, where abiotic stresses such as salinity and drought represent major constraints to crop productivity. These stresses induce complex physiological and biochemical alterations in plants, including osmotic imbalance, oxidative damage, and disruption of metabolic pathways, ultimately impairing growth and yield. In this context, the application of biostimulants has emerged as a sustainable strategy to enhance plant resilience. While synthetic products are widely available, growing attention is being directed toward natural bio-based products, particularly those derived from renewable biomasses and organic wastes, in line with circular economy principles. This review critically examines the current literature on bio-based products with biostimulant properties, with particular emphasis on vermicompost-derived extracts, humic-like substances, and macro- and microalgae extracts, focusing on their role in mitigating salt and drought stress in plants. The reviewed studies consistently demonstrate that these bio-products enhance plant tolerance to abiotic stress by modulating key physiological and biochemical processes, including hormonal regulation, activation of antioxidant defence systems, accumulation of osmoprotectants, and regulation of secondary metabolism. Moreover, evidence indicates that these bio-based inputs can improve nutrient use efficiency, photosynthetic performance, and overall plant growth under stress conditions. Overall, this review highlights the potential of non-microbial bio-based biostimulants as effective and sustainable tools for climate-resilient agriculture, while also underlining the need for further research to standardize formulations, clarify mechanisms of action, and validate their performance under field conditions. Full article

Soybean wax is a sustainable alternative to synthetic polymeric coatings in packaging due to its renewable, environmentally benign, and hydrophobic properties. In order to be effectively applied, however, soybean wax must be emulsified in water. The present work compares two stabilization approaches for soybean wax emulsions: a conventional surfactant-based emulsion (SE) using a mixture of nonionic surfactants (Span-80 and Tween-80), and a Pickering emulsion (PE) using cellulose nanocrystals combined with sodium alginate (CNC-SA) as an anionic stabilizer. The SE produced stable emulsions at 6 wt% Span-80/Tween-80 (at a HLB_mix value of 10) with a mean droplet size of 449 nm but limited storage stability (approximately 7 days under ambient conditions), while the PE achieved superior stability (approximately 1 month) at 1 wt% CNC-SA with a mean droplet size of 740 nm. The stabilized SE and PE were subsequently applied as coatings on three different types of paper substrates: northern bleached kraft (NBK) paper, copy paper, and cellulose nanofiber (CNF)-coated NBK paper. When applied to northern bleached kraft (NBK) paper, the SE coatings provided minimal improvements in barrier performance. The Cobb 60 value decreased slightly from 125 g/m² (control-no coating) to 86 g/m², indicating a negligible water barrier with immediate water absorption upon contact. In contrast, the Cobb 60 value of the PE-coated NBK paper decreased markedly from 125 g/m² to 39 g/m², confirming that the PE coating substantially enhances water resistance. The SE coating displayed a significant loss of water contact angle (WCA) from 85° to 0° within 20 s, showing limited water holdout capacity, whereas PE-coated NBK paper demonstrated strong water holdout, with the WCA decreasing only from 94° to 85° over 5 min. The SE coating achieved only a 14% reduction in water vapor transmission rate (WVTR), while the PE coating provided a greater reduction of 30%. In terms of oil resistance, both emulsion systems significantly enhanced the kit rating of the papers tested, e.g., from kit number 0 to 6–9 (paper dependent). The SE coating, however, experienced a substantial reduction in barrier integrity after folding, while the PE coating largely retained its oil barrier properties. Furthermore, the SE coating reduced the tensile strength of NBK paper by 41%, whereas the PE coating reduced it by only 7%. Overall, the comparative findings indicate that although the SE generated a smaller mean particle size, it offered minimal improvement in the water and oil barrier performance of paper and had a limited storage life. In contrast, the PE generated a larger mean particle size, but provided substantially greater water and oil resistance, and enhanced mechanical strength retention. In addition, the PE displayed an effective storage life of at least one month. The Pickering emulsion, formulated with all biologically derived components, therefore represents a viable, sustainable, bio-based alternative to synthetic polymeric coatings for packaging applications. Full article

Lactic acid is a crucial bio-based chemical with widespread applications in industries such as the food, chemical, bioplastic, and pharmaceutical industries. As demand for lactic acid rises, the search for efficient fermentation strains has become increasingly important. This study aimed to optimize fermentation conditions to enhance lactic acid production using Latilactobacillus sakei L-7. We began by screening key medium components and process parameters through single-factor experiments. Subsequently, we applied response surface methodology for a more comprehensive optimization. The optimal medium formulation was determined to be 40 g/L glucose, 39.54 g/L yeast extract, 10 g/L CH₃COONa, 6 g/L K₂HPO₄, 0.2 g/L MnSO₄, 0.4 g/L MgSO₄, and 1 mL/L Tween 80. Under the optimized fermentation conditions of 30.27 °C and pH 8.46, the lactic acid production reached 26.18 ± 0.44 g/L, a 50.6% increase compared to pre-optimization levels. These results offered preliminary support for utilizing L. sakei L-7 in the industrial production of lactic acid. Full article

Wild seeds constitute a taxonomically diverse and underexplored reservoir of C18-series bioactive fatty acids (BFAs) with significant nutritional, biomedical, and industrial relevance. This review integrates current knowledge on their lipid composition, metabolic architecture, and potential applications. Numerous wild taxa accumulate high levels of oleic, linoleic, α-linolenic, γ-linolenic, and stearidonic acids, while others synthesise structurally specialised compounds such as punicic, petroselinic, and sciadonic acids. These FAs, together with tocopherols, phytosterols, and phenolics, underpin antioxidant, anti-inflammatory, immunomodulatory, and cardiometabolic effects supported by in vitro and in vivo evidence. The occurrence of these unusual lipids reflects lineage-specific modulation of plastidial and endoplasmic-reticulum pathways, including differential activities of SAD, FAD2/3, Δ6- and Δ5-desaturases, elongases, and acyl-editing enzymes that determine the final acyl-CoA and TAG pools. Wild seed oils show strong potential for translation into functional foods, targeted nutraceuticals, pharmacologically relevant lipid formulations, cosmetic ingredients, and bio-based materials. However, their exploitation is constrained by ecological sustainability, oxidative instability of PUFA-rich matrices, antinutritional constituents, and regulatory requirements for novel lipid sources. This review positions wild seeds as high-value, underused lipid resources with direct relevance to health and sustainability. It underscores their potential to enhance nutritional security and offer alternatives to conventional oil crops. Full article

In an effort to reduce global dependence on fossil-based polymers and advance toward a more sustainable materials industry, research over recent decades has increasingly focused on the development of bio-based polymers and broadening their potential applications. Within this context, the present study investigates nanocomposites based on poly(butylene succinate-co-butylene adipate) (PBSA), reinforced with two types of nanofillers: silicon dioxide nanoparticles (SiO₂ NPs) and cellulose nanofibrils (CNFs). The main objective of this work is to examine how the morphology, geometry, and chemical nature of the nanofillers influence the thermal, mechanical, and barrier properties of PBSA, as well as its biodegradability. For each nanofiller, three formulations were prepared, containing 1, 2, and 5 wt% of filler, respectively. Scanning electron microscopy (SEM) analysis confirmed good dispersion and minimal aggregation in the SiO₂-based systems, whereas marked aggregation was observed in the CNF-based samples. Thermal analysis indicated that the intrinsic thermal properties of neat PBSA were largely preserved. Mechanical testing revealed improvements in both the elastic modulus and elongation at break for most nanocomposite samples. In particular, CNFs provided the most consistent reinforcing effect, with enhancements of approximately 40% in the elastic modulus (495.4 vs. 356.4 GPa in neat PBSA) and 52% in elongation at the break (185.1 vs. 122.0% in neat PBSA) with 5 wt% loading. Additionally, the incorporation of nanofillers did not alter the surface hydrophilicity, but it did improve the oxygen barrier performance and enhanced disintegration under composting conditions. Overall, these findings demonstrate the promising potential of PBSA-based nanocomposites for sustainable rigid packaging applications. Full article

Driven by environmental concerns, the packaging industry is shifting toward high-performance and bio-based coating alternatives. In this research, poly(methylmethacrylate) (PMMA) and modified cellulose nanocrystal (m-CNC) were employed as reinforcing agents to develop sustainable poly (lactic acid)-based coatings for packaging applications. Various formulations, influenced by polymer matrix blends and m-CNC loadings (1–5%), were prepared using solvent and applied as protective coating on cardboard paper substrates. The grammage of polymeric coatings (CG) on paper was also investigated using various wet film thicknesses (i.e., 150–250 μm). Accordingly, key parameters including water contact angle, thermal behavior, mechanical performances and barrier properties were systematically evaluated to assess the effectiveness of the developed nanocomposite coatings. As a result, nonylphenol ethoxylate surfactant-modified cellulose nanocrystals exhibited good dispersion and stable suspension in chloroform for one hour, improving compatibility and interaction of polymer–CNC fillers. The water vapor permeability (WVP) of PLA-coated papers was significantly reduced by blending PMMA and increasing the content of m-CNC nanofillers. Furthermore, CNC incorporation enhanced the oil resistance of PLA/PMMA-coated cardboard. Pronounced improvements in barrier properties were observed for paper substrates coated with dry coat weight or CG of ~20 g/m² (corresponding to 250 μm wet film thickness). Coatings based on blended polymer—particularly those reinforced with nanofillers—markedly enhanced the hydrophobicity of the cardboard papers. SEM-microscopy confirmed the structural integrity and morphology of the nanocomposite coatings. Regarding mechanical properties, the upgraded nanocomposite copolymer (PLA-75%/PMMA-25%/m-CNC3%) exhibited the highest bending test and tensile strength, achieved on coated papers and free-standing polymeric films, respectively. Based on DSC analysis, the thermal characteristics of the PLA matrix were influenced to some extent by the presence of PMMA and m-CNC. Overall, PLA/PMMA blends with an optimal amount of CNC nanofillers offer promising sustainable coatings for the packaging applications. Full article

Viscoelastic polyurethane foams were prepared using four different bio-based polyols derived from coconut oil (CO), palm oil (PO), duck fat (DF), and pork fat (PF), employing up to 20 wt.% of the polyol component in a conventional formulation. The introduction of bio-polyols into the polyurethane formulation gave rise to an early minor decomposition of modified foams at low temperatures; however, the overall thermal stability improved slightly by the elimination of some intermediate decomposition stages. The glass transition temperature of foams was only moderately influenced and remained in the typical temperature range (around 10 °C). The effect of biopolyol type and content (5–20 wt.%) on the mechanical properties of the foams was investigated over the temperature range −20 to 40 °C. At 20 and 40 °C, all foams exhibited comfortable viscoelastic properties suitable for furniture applications. Hysteresis and the damping behavior of foams were also influenced by biopolyol type and concentration, with CO and DF providing enhanced energy absorption. Overall, these bio-based foams demonstrate potential for eco-friendly, high-performance applications, although their use at temperatures below 10 °C may be limited by increased stiffness. Full article

The fiberboard industry remains heavily reliant on synthetic, formaldehyde-based adhesives, which, despite their cost-effectiveness and strong bonding performance, present significant environmental and human health concerns due to volatile organic compound (VOC) emissions. In response to growing sustainability imperatives and regulatory pressures, the development of non-toxic, renewable, and high-performance bio-based adhesives has emerged as a critical research frontier. This review, conducted through both narrative and systematic approaches, synthesizes current advances in green adhesive technologies with emphasis on lignin, tannin, starch, protein, and hybrid formulations, alongside innovative synthetic alternatives designed to eliminate formaldehyde. The Evidence for Policy and Practice Information and Coordinating Centre (EPPI) framework was applied to ensure a rigorous, transparent, and reproducible methodology, encompassing the identification of research questions, systematic searching, keywording, mapping, data extraction, and in-depth analysis. Results reveal that while bio-based adhesives are increasingly capable of approaching or matching the mechanical strength and durability of urea–formaldehyde adhesives, challenges persist in terms of water resistance, scalability, cost, and process compatibility. Hybrid systems and novel crosslinking strategies demonstrate particular promise in overcoming these limitations, paving the way toward industrial viability. The review also identifies critical research gaps, including the need for standardized testing protocols, techno-economic analysis, and life cycle assessment to ensure the sustainable implementation of these solutions. By integrating environmental, economic, and technological perspectives, this work highlights the transformative potential of green adhesives in transitioning the fiberboard sector toward a low-toxicity, carbon-conscious future. It provides a roadmap for research, policy, and industrial innovation. Full article

The increasing environmental impact of synthetic antifouling paints has stimulated the search for natural, eco-friendly alternatives. In this study, alcoholic and aqueous extracts of the macroalgae Ulva ohnoi and Asparagopsis taxiformis were evaluated for their antifouling potential on aluminum substrates representative of boat hulls. Extracts were applied to aluminum plates coated with gelcoat under three different surface conditions (non-worn, worn, highly worn). The treated panels were submerged at 5 m and biofilm and fouling development was monitored every 96 h using digital imaging and quantitative segmentation. All treated surfaces exhibited significantly lower fouling colonization than the untreated control (p < 0.001). Among treatments, the aqueous extract of A. taxiformis produced the lowest degree of colonization across all surface conditions, while U. ohnoi extracts showed moderate antifouling activity. Increased surface wear enhanced overall colonization but did not suppress extract efficacy. These results demonstrate that both algal species possess active compounds capable of inhibiting early biofilm formation on marine substrates. Although less potent than conventional biocidal coatings, their biodegradability and absence of ecotoxicity represent a substantial environmental advantage. Future studies should focus on the chemical characterization of active metabolites, the formulation of hybrid bio-based coatings, and long-term field testing under dynamic marine conditions. Full article

This work presents an approach to water-dispersible polylactide (PLA) particle fabrication and their application in low-temperature film formation using a combination of mechanical dispersion and ultrasonication techniques. Stable PLA dispersions were obtained after removal of surfactant and allowed for thin-film preparation, exhibiting a significantly reduced minimum film formation temperature (MFFT) from 128 °C to 80 °C after reducing the characteristic particle size from ~2.2 µm to ~140 nm. To tailor the interfacial behavior and mechanical flexibility of the resulting coatings, a set of conventional and bio-based plasticizers was evaluated, including epoxidized fatty acids, PEG-400, and several hydrophobic deep eutectic solvents (HDESs) synthesized from menthol and carboxylic acids. Compatibility between PLA and each plasticizer was predicted using Hansen solubility parameters. The efficiency of plasticization was assessed through glass transition temperature suppression in solvent-cast films. The combination of submicron PLA particles and selected plasticizers enabled film formation at temperatures as low as 48 °C, confirming the potential of these systems for energy-efficient coating technologies. Furthermore, composite coatings incorporating micro-sized cellulose fibers (L/D ≈ 10.5–11.5) regenerated from agricultural residues were successfully obtained, demonstrating the feasibility of integrating bio-derived fillers into waterborne PLA formulations. In this study, the use of water-insoluble deep eutectic solvents type plasticizers for PLA coatings from water dispersions was reported for the first time. This establishes a foundation for developing sustainable, low-VOC, and low film formation temperature PLA-based coating materials. Full article

The development of sustainable, water-based conductive coatings is essential for advancing environmentally responsible wearable and printed electronics. Achieving high electrical conductivity and wash durability remains a key challenge. This is largely dependent on the compatibility between the polymer matrix, the conductive filler and the substrate surface. In this study, a facile formulation strategy is proposed by directly integrating few-layer graphene (FLG, 2.5 wt%) into commercial bio-based thermoplastic polyurethanes (TPUs), combined with polyvinylpyrrolidone (PVP) as a dispersing agent. The investigation focuses on how the segmental architecture of four TPUs with different structure and hard–soft segments composition influences filler dispersion, mechanical integrity, and electrical behavior. Coatings were deposited onto flexible substrates, including textiles and paper, using a bar-coating process and were characterized in terms of morphology, thermal properties, electrical conductivity, and wash resistance. The results demonstrate that TPUs containing a higher presence of hard segments interact more effectively with hydrophobic surfaces, while TPUs with a higher contribution of soft segments improve adhesion to hydrophilic substrates and facilitate the formation of the percolation network, underling the role of TPU microstructure in controlling interfacial interactions and overall coating performance. The proposed comparative approach provides a sustainable pathway toward durable, high-performance, and washable electronic textiles and paper-based devices. Full article

This study explores the potential of pine bark—a highly accessible and underexploited by-product of forestry and food processing—as a renewable raw material for rigid polyurethane (PUR) foam production. Under optimal extraction conditions, water-soluble extractives rich in carbohydrates were isolated from biomass with a yield of 25% and subsequently condensed with propylene carbonate (PC) to produce bio-based polyols. The polyols synthesized at a PC/OH molar ratio ranging from 1 to 5 were incorporated into rigid PUR foam formulations as substitutes for commercial polyether polyols. The foams containing bio-polyols synthesized at a PC/OH ratio of 3 demonstrated the highest compressive strength and thermal insulation performance, exceeding those of the reference material by 30% and 9%, respectively, and exhibited enhanced thermo-oxidative stability. Incorporation of extracted bark up to 10 wt% as a filler in the PUR matrix led to a decrease in mechanical properties to the level of the reference foam and a 19% reduction in thermal insulation capacity, without affecting the closed-cell content. Cone calorimetry revealed that both filled and unfilled bio-polyol-based PUR foams exhibited lower degradation rate, heat release rate, and total smoke release compared with the reference material, indicating reduced flammability and a lower tendency toward fire propagation. Full article

The global transition from internal combustion engines (ICEs) to hybrid (HEVs) and electric vehicles (EVs) is fundamentally reshaping lubricant design requirements, driven by evolving thermal demands, electrical constraints, and material compatibility challenges. Conventional ICE lubricants are primarily formulated to withstand high operating temperatures, mechanical stresses, and combustion-derived contaminants through established additive chemistries such as zinc dialkyldithiophosphate (ZDDP), with thermal stability and wear protection as dominant considerations. In contrast, HEV lubricants must accommodate frequent start–stop operation, pronounced thermal cycling, and fuel dilution while maintaining performance across coupled mechanical and electrical subsystems. EV lubricants represent a paradigm shift, where requirements extend beyond tribological protection to include electrical insulation and conductivity control, thermal management of electric motors and battery systems, and compatibility with copper windings, polymers, elastomers, and advanced coatings, alongside mitigation of noise, vibration, and harshness (NVH). This review critically examines lubricant behavior, formulation strategies, and performance requirements across ICE, HEV, and EV powertrains, with specific emphasis on heat transfer, electrical performance, and lubricant–material interactions, covering mineral, synthetic, and bio-based fluids. Additionally, regulatory drivers, sustainability considerations, and emerging innovations such as nano-additives, multifunctional and smart lubricants, and AI-assisted formulation are discussed. By integrating recent research into industrial practice, this work highlights the increasingly interdisciplinary role of tribology in enabling efficient, durable, and sustainable mobility for next-generation automotive systems. Full article