Bone tissue engineering requires scaffolds that combine high bioactivity with sufficient mechanical strength to support tissue regeneration. In this study, a novel strategy was developed to fabricate hierarchical magnetic mesoporous bioactive glass scaffolds reinforced with 7.5 wt
With the rapidly increasing demand for paper-based packaging, the development of sustainable coating materials is essential to enhance surface functionality and barrier performance. Gracilaria fisheri seaweed is a promising source of edible, biodegradable agar coatings. Given the structural similarity between agar and κ-carrageenan, G. fisheri-derived agar may serve as a lower-cost alternative to κ-carrageenan coatings. In this study, G. fisheri-derived agar coatings (GF), obtained via hot water extraction, were applied to paper substrates and compared with coatings prepared from pure κ-carrageenan and their mixtures to evaluate the coating functionalities mainly for single-use paper-based packaging. The GF coatings provided effective oxygen barrier performance (OTR 1.6×105 cc/m2⋅day) and excellent oil resistance (Cobb60 <10 g/m2) comparable to κ-carrageenan, while offering greater processability during coating application due to weaker gelation. Importantly, GF coatings exhibited clear heat-sealability with seal strength ( 300–400 N/m) comparable to starch-based films, whereas κ-carrageenan coatings showed no apparent heat-sealing ability. However, their tensile strength and Young’s modulus decreased significantly in machine direction. During application test with oil-rich food, GF coatings also had limited thermal resistance (Tg ≈ 69 °C), restricting prolonged contact with high-temperature, oil-rich foods. Therefore, further improvements in thermal stability are required, potentially through polymer blending, crosslinking, or reinforcing fillers incorporation.
Due to their excellent hydrophilicity, antibacterial properties, and molecular designability, quaternary ammonium salts (QAS) have attracted considerable interest. In this study, four Gemini quaternary ammonium salts (GQAS-1, GQAS-2, GQAS-3, and GQAS-4), each containing two quaternary ammonium groups and varying numbers of hydroxyl groups, were designed and synthesized as hydrophilic chain extenders. These were subsequently used as chain extenders in cationic waterborne polyurethanes (WPUs). The WPUs were prepared using isophorone diisocyanate (IPDI), polybutylene glycol (PTMG), 1,4-butanediol (BDO), and GQAS-1, GQAS-2, GQAS-3, or GQAS-4. The results show that GQAS-4, which contains five hydroxyl groups, significantly enhances the performance of the resulting WPU. The WPU modified with GQAS-4 exhibits excellent emulsion stability. The five hydroxyl groups in GQAS-4 alter the crosslinking degree of the WPU molecular structure, endowing the film with a tensile strength of up to 5.4 MPa. Furthermore, when the GQAS-4 content is increased to 8.6
This study presents a coupled route for recovering intracellular polyhydroxyalkanoates (PHA) and extracellular polymeric substances (EPS) from waste-activated sludge. A direct accumulation approach was applied without prior microbial enrichment, using biomass collected from two membrane bioreactor (MBR) configurations: a conventional activated sludge MBR and a microalgae-sludge MBR. Both systems achieved comparable PHA accumulation kinetics and final contents, reaching approximately 31
Enhancing mechanical load-bearing capacity while accelerating degradation rates is a critical challenge for polycaprolactone (PCL) scaffolds in tissue engineering applications. To address this, polycaprolactone/magnesium-zinc alloy (PCL/Mg-Zn) composite porous scaffolds were fabricated using triply periodic minimal surface (TPMS) design combined with selective laser sintering (SLS) technology. On the one hand, the Mg-Zn alloy particles embedded in the matrix act as a rigid reinforcing phase, effectively bearing greater loads and inhibiting crack propagation, thereby significantly enhancing the scaffold’s mechanical properties. On the other hand, the galvanic corrosion effect between the Mg-Zn alloy particles and the catalytic degradation cycle formed between the PCL and Mg-Zn alloy synergistically regulate the scaffold’s degradation behavior. More interestingly, the incorporation of the Mg-Zn alloy significantly enhanced the scaffold’s bio-mineralization capacity, enabling rapid HA deposition in SBF solution. Experimental results indicate that the mechanical strength of the PCL/Mg-Zn composite scaffold was significantly improved, with compressive and tensile strengths increasing by 98.2
The chemical preservation and antifungal protection of historical cellulosic documents remain a significant challenge in sustainable conservation science. Traditional synthetic fungicides often pose environmental risks and lack long-term compatibility with the delicate cellulose matrix. In this study, a sustainable multifunctional coating was developed by encapsulating thyme essential oil within chitosan nanoparticles and applied to historical cellulose-based paper. The antifungal performance of thyme essential oil (EO), nanochitosan (NC), and the resulting nanocomposite (ECC) was evaluated against Aspergillus niger and Penicillium sp., two common fungi found in libraries and archival collections. The protective effect of the nanocomposite was further assessed through thermal and biological aging tests by monitoring changes in tensile strength, acidity, color changes, cellulose structure, and fiber morphology. The results show that the nanocomposite enhances the antifungal efficiency and solves the shortcomings of chitosan and Thyme essential oils in the paper. The nanocomposite exhibited inhibition zones of 29 mm against Aspergillus niger and 42 mm against Penicillium sp after 7 days. In addition, the treated paper retained 98.6
A sustainable and efficient strategy for fabricating a chitosan-based waterborne polyurethane (CH-WPU) sorbent through in situ synthesis is reported in the present study. In this system, chitosan performs a dual role—serving simultaneously as a bio-polyol in polyurethane formation and as a solid emulsifier that stabilizes the pickering emulsion—thereby simplifying the formulation. The successful grafting of urethane linkages onto the chitosan backbone was confirmed by FTIR and XPS analyses. Thermogravimetric (TGA) and differential scanning calorimetry (DSC) results revealed enhanced thermal stability of the CH-WPU network compared with pristine chitosan. The material’s chemical durability was evaluated through solubility testing under harsh acidic and alkaline conditions (2 M acetic acid, HCl, H₂SO₄, NaOH, and NaOCl, 75 °C), and morphological integrity was examined using SEM. The BET results clearly showed that the modification of the chitosan successfully shifted it from a non-porous material with a low surface area of 0.4047 m²/g into a porous structure having a high surface area (12.2520 m²/g). The pseudo-first-order kinetic model and Langmuir model provided a better fit to the experimental data with R² values of 0.971 and 0.990, respectively. The optimized CH-WPU exhibited outstanding adsorption capacity toward Congo red (CR) dye, reaching 276.2 mg g⁻¹. Moreover, the adsorbent demonstrated excellent reusability, retaining nearly 72
Ovarian cancer remains a significant health challenge, highlighting the need for innovative therapeutic strategies. This study aims to evaluate the cytotoxic and antioxidant properties of oxidized-acetylated multi-walled carbon nanotubes functionalized with Chitosan-Folic Acid loaded with Resveratrol (Oxidized-Acetylated MWCNT-Chi-FA-Resveratrol) on the A2780 ovarian cancer cell line and to elucidate the underlying mechanisms of action. Nanoparticle characterization was performed using dynamic light scattering (DLS) for particle size and zeta potential analysis, field emission scanning electron microscopy (FESEM) for morphological characterization, and Fourier-transform infrared (FTIR) spectroscopy to confirm functional groups. Encapsulation efficiency was assessed spectrophotometrically, and drug release profiles were measured over 80 h with early time points (0–12 h) to capture burst release. In vitro biological assays included the MTT assay for cytotoxicity, Annexin V-FITC/PI staining and AO/PI staining for apoptosis detection, and real-time PCR for caspase-3, -8, and -9 gene expression. Antioxidant activity was evaluated using ABTS and DPPH radical scavenging assays. The DLS analysis indicated a Z-average particle size of 95.38 nm with a low polydispersity index (PDI) of 0.2420. The zeta potential was -15.56 ± 11.64 mV, indicating poor colloidal stability. The encapsulation efficiency for Resveratrol was 83.7
This study investigated the regulatory effects and underlying the mechanisms of microbial-fermented Chinese yam polysaccharides (CYPs) in a cyclophosphamide (CTX)-induced immunosuppressed mouse model. Our findings demonstrated that CYPs mitigated weight loss, elevated immune organ indices, and modulated the secretion of cytokines (TNF-α, IL-6, and IL-1β) and immunoglobulins (IgA, IgG, and IgM). Histopathological observations showed that CYPs alleviated CTX-induced morphological alterations in immune organs, as indicated by improved thymic and splenic tissue architecture. Moreover, 16 S rRNA sequencing revealed that CYPs altered gut microbiota composition and were associated with partial recovery of CTX-induced microbial dysbiosis. Integrated metabolic profiling indicated that the immunomodulatory efficacy of CYPs was partially associated with the regulation of arachidonic acid metabolism, as well as the amino acid and aminoacyl-tRNA biosynthesis. Briefly, these results suggest that CYPs potentially improve the immune-related indicators in CTX-induced immunosuppressed mice, accompanied by changes in immune organ integrity, gut microbiota composition, and host metabolic pathways.
In the post-pandemic era, biodegradable materials with antibacterial properties effectively meet safety needs for protective applications. However, although tannic acid (TA) has excellent antimicrobial properties, its abundant phenolic hydroxyl groups make it uneven dispersion in the polymer matrix. In this study, nano-TiO2-TA (TiTA) hybrid filler was prepared firstly and then mixed with poly (butylene adipate-co-terephthalate) (PBAT) (PBAT/TiTA) via melt blending. Notably, TiTA hybrid filler not only enhanced the degradability and mechanical properties of PBAT, but also endowed strong antibacterial activity with Ultraviolet (UV)-free irradiation, which overcome the limitation of UV irradiation to the antibacterial activity of TiO2. When the TiTA content was 7.5 wt
Polyhydroxyalkanoates (PHAs) are sustainable alternatives to petroleum-based plastics, yet their commercialisation remains limited by the lack of efficient strains and high production costs. To address this challenge, an improved PHA synthase, PhaCG8 was cloned into Cupriavidus necator Re2058. Compared with its parental synthase, PhaCG8 was shown to promote the formation of higher-molecular-weight polymers and fewer but larger intracellular PHA granules. The performance of the new recombinant strain was evaluated using crude palm kernel oil (CPKO) and fructose, revealing higher polymer molecular weight with fewer and larger granules compared to C. necator Re2058/pHT1-CBP-M-CPF4 although a direct mechanistic relationship between granule morphology and Mw has yet to be established. To tackle the high production cost, solvent-extracted non-edible palm fibre oil (PFO) was evaluated as a sustainable carbon source for PHA production using the new recombinant strain. PFO used in this study supported efficient growth and polymer accumulation, achieving 124.3 g/L biomass with 83.1 g/L PHA under fed-batch conditions, corresponding to a polymer yield coefficient of 0.64 g/g and a volumetric productivity of 1.07 g/L·h. A biological recovery approach using mealworms (Tenebrio molitor) was also implemented, achieving 82
Polyethylene terephthalate (PET) is a widely used synthetic polymer and a persistent environmental pollutant due to its resistance to natural degradation. Polyethylene terephthalate hydrolase (PETase) and mono(2-hydroxyethyl) terephthalate hydrolase (MHETase) from Ideonella sakaiensis offer a promising enzymatic route for PET hydrolysis. In this study, petase and mhetase genes were cloned separately and together into pETDuet-1 vectors, enabling co-expression of genes in a single host. Purified PETase and MHETase were characterized using soluble substrates and PET films. PETase showed the highest apparent activity toward p-nitrophenyl butyrate, with activity decreasing with increasing acyl chain length. The tested metal ions did not enhance PETase activity, and MgCl2 caused the strongest inhibition. Recombinant cell-based PET hydrolysis was evaluated at different temperatures (20, 25, and 37 °C) and pH values (6–9), with the highest soluble product formation observed at 37 °C and pH 8. HPLC analysis showed that co-culture and single-vector co-expression increased terephthalic acid (TPA) formation compared with single-enzyme systems. The BHET/TPA molar ratio decreased from 0.195 in co-culture to 0.156 under co-expression, indicating improved intermediate conversion when both genes were expressed in the same host. FTIR, DSC, and SEM analyses supported surface-level PET modification, including changes in ester-associated bands, crystallinity, and localized erosion. Overall, single-vector co-expression of petase and mhetase improved soluble product distribution and intermediate turnover compared with co-culture.
As biodegradable plastics become integrated into the modern economy, soil contamination by biodegradable microplastics (MPs) has raised concerns owing to their potential to alter soil organic matter (SOM), an important carbon reservoir, through priming effects. Priming effects refer to the acceleration (positive) or suppression (negative) of SOM decomposition following an external carbon input. Previous studies have relied on carbon-13 isotope analysis, which lacks the resolution required for precise carbon tracing, to study the priming effects of biodegradable MPs. Herein we present a novel approach combining accelerator mass spectrometry-based radiocarbon (carbon-14) analysis with a closed-jar incubation system to quantify the priming effects of two fossil-based biodegradable MPs, poly(ε-caprolactone) (PCL) and poly(butylene adipate-co-terephthalate) (PBAT). This method enables high-resolution time-resolved partitioning of biogenic and fossil-derived carbon sources. Both biodegradable MPs show a net negative priming effect (up to − 35.4 µg C g− 1 soil for PCL after 9 d, and − 9.6 µg C g− 1 soil for PBAT after 24 d), with transient positive priming observed at certain time points. This study provides a robust approach for accurate assessment of the priming effects of biodegradable plastics on SOM and offers a potential analytical framework to devise end-of-life management strategies for biodegradable plastics in agroecosystems.
Regeneration of impaired tissues requires advanced biomaterials that integrate mechanical integrity with antioxidant functionality and biocompatibility. In this study, we fabricated a bioactive κ-carrageenan–egg albumin (KC–EA) hydrogel incorporating a curcumin–Aloe vera (CUR–ALV) composite via ionotropic gelation. Incorporation of the CUR–ALV composite enhanced both structural and functional properties of the hydrogel, as characterized through mechanical testing, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and swelling analyses. The composite-loaded hydrogel exhibited enhanced mechanical performance relative to the KC–EA hydrogel, while SEM analysis revealed increased surface roughness and heterogeneous microdomains suggesting successful composite incorporation. The hydrogel exhibited pH-responsive curcumin release, reaching a maximum cumulative release of approximately 80
Poly(lactic acid) (PLA) is a potential material owing to its biodegradability; however, its inherently low crystallinity limits its large-scale use. This study reports the synthesis of glyceryl lactate (GLY LAC) by condensation polymerization at 190 °C for 8 h from bio-based sources of controllable molecular weight (1:3, 1:6, 1:9, and 1:12 molar ratios of glycerol and lactic acid) and their application as highly effective nucleating agents for PLA. The success and purity of the polymerization reaction of glyceryl lactate (GLY- LAC) were proven using acid value, viscosity, FTIR, and NMR spectroscopy. DSC analysis indicated that GLY LAC with a 1:6 molar ratio is the most suitable compound to act as a nucleating agent for PLA, which yielded a crystallinity degree of 87.8 ± 1.7
This study investigates a bio-based precursor for carbon materials by directly copolymerizing unmodified LignoBoost lignin (LB) with non-fossil derived acrylonitrile (AN) via aqueous free radical polymerization (FRP), forming lignin–polyacrylonitrile (PAN) graft-type copolymers. In contrast to conventional approaches, the process avoids organic solvents and lignin functionalization. Key parameters such as lignin activation, the order of reactant addition, and the reactivity of functional groups were analyzed. Activation was achieved through in situ radical generation without introducing permanent chemical modifications. Copolymers with increasing LB initial contents (3.4, 17.5, and 33 wt
Polyurethane (PU) is widely used across various industrial sectors. Its strong chemical resistance renders conventional recycling methods inefficient. Developing greener and more energy-efficient depolymerization strategies is therefore essential. Previous methods for DES-based depolymerization of PU usually require high temperatures and long reaction times. This study proposes a two-stage microwave-thermal treatment process to accelerate PU degradation under milder operating conditions. This study investigates deep eutectic solvents (DES) as sustainable media for PU degradation to identify an efficient treatment system that lowers processing temperature and reaction time while improving product recovery. Choline chloride (ChCl)-based DES formulated with urea, glycerol, and levulinic acid was synthesized and characterized for density, viscosity, and thermal stability. PU depolymerization was evaluated under heat treatment (160 ℃ to 180 ℃, 120 to 480 min), microwave irradiation (360 W to 700 W, 3 to 7 min), and a two-stage microwave-thermal treatment process approach. Structural analysis and degradation kinetics of the products were conducted using 1H NMR. Incorporating microwave irradiation at 360 W for 3 min before heating resulted in 100
Responsive polymers have attracted considerable attention over the past two decades due to their potential in advanced functional applications. The practical implementation of these materials often requires multicomponent systems comprising polymer blends and functional nanofillers. In this study, a highly efficient stimuli-responsive nanocomposite was developed, based on thermoplastic polyurethane (TPU) and polylactic acid (PLA) plasticized with low-molecular-weight polyethylene glycol (PEG). Cellulose nanocrystals (CNCs) as a biocompatible and renewable nanofiller and multi-walled carbon nanotubes (MWCNTs) as a conductive nanofiller were incorporated to enhance mechanical properties and electroactivity. The results demonstrated that the nanofillers effectively regulated phase morphology, elasticity, and shape memory behavior, with the optimal performance achieved through the hybrid integration of these nanofillers. The addition of PEG reduced the glass transition temperature of PLA by 19 °C, thereby improving the recovery ratio. Moreover, the PLA matrix exhibited excellent shape fixity performance, with a fixity ratio of at least 96.8
Compared to neat magnetic ionic liquids (MILs), supported ionic liquids (SILs) provide notable provide notable benefits, particularly in terms of facile separation and reusability, while significantly mitigating common limitations. MILs often suffer from disadvantages such as high cost, potential toxicity, and challenges associated with product isolation. To address this issue, a xanthan gum based supported magnetic ionic liquid ([XGIM][FeCl4]) was synthesized by immobilizing IL onto backbone of xanthan gum (XG) which is the most prevalent polysaccharide in nature and economical in industrial waste followed by anion exchange with anhydrous FeCl3 by using ultra probe sonication. [XGIM][FeCl4] was thoroughly characterized using various techniques such as FTIR, FE-SEM, EDS, elemental, TGA, vibrational Raman spectra, VSM and EPR. In addition, [XGIM][FeCl4] served as an effective organocatalyst for synthesizing thioether-linked 4-hydroxycoumarin-benzothiazole, benzoxazole and benzimidazole derivatives under mild reaction conditions. Therefore, incorporating a magnetic core as the counter anion with the xanthan gum cationic framework enables rapid magnetic separation without filtration or centrifugation, allowing up to nine reuse cycles.
