Search Results (153)

Efficient conversion of biomass-based platform molecules into high-value derivatives is recognized as one formidable challenge in biomass upgrading. In this work, a one-pot deep eutectic solvents-assisted solvothermal method was developed for the modification of the commercial Pt/C catalysts by introducing a secondary metal (M = Sn, Bi, Ge, Sb, Pb). The structural and electronic properties of the catalysts were precisely tuned. Among the screened metals, the addition of Sn yielded the most significant improvement in catalytic activity. The optimized PtSn_0.5/C-140 catalyst achieved superior furfural (FAL) conversion and furfuryl alcohol (FOL) selectivity under mild conditions (20 °C, 2 MPa H₂). Comprehensive characterizations, including XRD, HRTEM, XPS, and H₂-TPD, confirmed the formation of Pt-Sn solid-solution phase. Furthermore, Characterization and reaction results revealed that the electronic and geometric effects induced by Sn modulated Pt active sites, significantly enhancing the adsorption of the active H species. Additionally, the SnO_x species adjacent to the Pt-Sn sites served as hydrogen spillover acceptors, further accelerating the hydrogenation process. The synergy between the Pt-Sn solid-solution phase and SnO_x species is identified as the origin of the superior performance at room temperature. These findings provide a new strategy for the design of high-performance biomass conversion catalysts by upgrading commercial noble metal catalysts. Full article

This study aimed to synthesize a magnetic biochar@ZIF-8 composite derived from almond shell biomass for the adsorption of fluoroquinolones (FQs) from aqueous media. The biochar was prepared under different pyrolysis conditions using a central composite design (CCD) based on temperature and residence time, with biochar yield (%) and ofloxacin adsorption capacity selected as the response variables. Subsequently, the composite was obtained by combining KOH-activated biochar with ZIF-8 and magnetic particles, producing a hierarchically porous material with enhanced surface area and functional groups favorable for adsorption. The physicochemical and morphological properties of the composite were characterized by SEM–EDS, FTIR, BET, TGA, and XRD analyses, confirming the successful incorporation of ZIF-8 and magnetic phases onto the biochar surface. The adsorption performance was systematically evaluated by studying the effects of pH and contact time. The kinetic data fitted well to the pseudo-second-order model, suggesting that chemisorption predominates through π–π stacking, hydrogen bonding, and coordination interactions between FQ molecules and the active sites of the composite. Furthermore, the material exhibited high reusability, maintaining over 84% of its adsorption capacity after four cycles, with efficient magnetic recovery without the need for filtration or centrifugation. Overall, the magnetic biochar@ZIF-8 composite demonstrates a sustainable, cost-effective, and magnetically separable adsorbent for water remediation, transforming almond shell waste into a high-value material within the framework of circular economy principles. Full article

Most polymeric plastics used as food packaging are obtained from petroleum or made with non-biodegradable synthetic molecules, which slowly degrade and leach into the environment, resulting in the accumulation of microplastics along the trophic chains. To mitigate these impacts, biodegradable packaging derived from agro-industrial biomass residues has emerged as a promising alternative. In this study, bio-based methylcellulose films reinforced with cellulose nanocrystals (CNCs) extracted from low-quality coffee beans were developed and fully characterized. The extracted CNCs presented a needle-like morphology, with an average height of 7.27 nm and a length of 221.34 nm, with 65.75% crystallinity, were stable at pH 7–8, and presented thermogravimetric mass loss of 8.0%. Methylcellulose films containing 0.6% w/w of CNC were produced by casting and characterized in terms of thermal, mechanical, and optical properties. Notably, the incorporation of CNCs resulted in significantly more flexible and less rigid films, as evidenced by the higher elongation at break (57.90%) and lower Young’s modulus (0.0015 GPa) compared to neat methylcellulose film. The tensile strength was not affected (p > 0.05). Additionally, the MCNC 0.6% films effectively blocked UV light in the 200–300 nm range without compromising transparency. Altogether, these findings underscore the MCNC 0.6% film as a flexible, biodegradable packaging material suitable for food industry application. Full article

Furfural (FAL), an important biomass-derived platform molecule, plays a vital role in bridging biorefineries and the production of high-value chemicals through its selective hydrogenation to furfuryl alcohol (FOL). In this work, a series of Cu-based bimetallic catalysts (Cu₅Ni_x/SiO₂) were prepared by a simple impregnation method and exhibited outstanding catalytic performance for the hydrogenation of furfural under the mild conditions. When the loading of Ni was 2 wt%, the optimal catalytic activity was obtained at 150 °C and 1 MPa H₂, achieving a furfural conversion of 97.3%. This catalyst also showed excellent stability, maintaining high activity and selectivity toward FOL after five consecutive reaction cycles. Structural characterizations using X-ray diffraction (XRD), Hydrogen temperature-programmed reduction (H₂-TPR), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) revealed strong electronic interactions between Cu and Ni species. The introduction of Ni promoted the reduction of Ni²⁺ and improved the dispersion of Cu, which in turn increased the number of accessible active sites and facilitated the hydrogenation process. This synergistic effect between Cu and Ni provides an efficient and low-cost strategy for the selective hydrogenation of biomass-derived furfural to high-valued chemicals. Full article

Water resource management and agricultural practices in the Mediterranean region, characterised by the excessive use of pesticides, pose significant environmental and human health challenges. As they can be easily and inexpensively produced from various biomass sources, biochars are frequently recommended as a low-cost secondary decontamination strategy to address soil contamination problems. This study investigates the properties and sorption behaviours of biochars produced in a low-cost metallic kiln using local rosemary, giant reed, St. John’s wort, olive, cypress, and palm tree biomass residues to evaluate their potential for environmental remediation, with a special focus on the mobility and retention of contaminants. Analytical and experimental techniques were employed to characterise the biochars’ physicochemical attributes and sorptive capacities. The core analyses included measurement of basic physicochemical properties, including pH, electrical conductivity, functional group identification via Fourier transform infrared (FTIR) spectroscopy, and the molarity of ethanol droplet (MED) test to assess the surface hydrophobicity. Batch sorption experiments were conducted using methylene blue (MB) and two fluorescent tracers—uranine (UR) and sulforhodamine-B (SRB)—as proxies for organic contaminants to assess the adsorption efficiency and molecule–biochar interactions. Furthermore, the adsorption isotherms at 20 °C were fitted to different models to assess the biochars’ specific surface areas. Thermodynamic parameters were also evaluated to understand the nature and strength of the adsorption processes. The results highlight the influence of feedstock type on the resulting biochar’s properties, thus significantly affecting the mechanism of adsorption. Rosemary biochar was found to have the highest specific surface area (SSA) and cation exchange capacity (CEC), allowing it to adsorb a wide range of organic molecules. Giant reed and palm tree biochars showed similar properties. In contrast, wood-derived biochars generally showed very low SSA, moderate CEC, and low hydrophobicity. The contrasting properties of the three dyes—MB (cationic), UR (anionic), and SRB (zwitterionic)—enabled us to highlight the distinct interaction mechanisms between each dye and the surface functional groups of the different biochars. The reactivity and sorption efficiency of a biochar depend strongly on both the nature of the target molecule and the intrinsic properties of the biochar, particularly its pH. The findings of this study demonstrate the importance of matching biochar characteristics to specific contaminant types for optimised environmental applications, providing implications for the use of tailored biochars in pollutant mitigation strategies. Full article

The emergence of drug-resistant Candida species has created an urgent need for non-toxic molecules that inhibit fungal growth, biofilm development, and hyphal formation. In this study, fifty multi-halogenated indole derivatives were screened against ten Candida species, including azole-resistant C. albicans, C. auris, C. glabrata, and C. parapsilosis. Among them, 4,6-dibromoindole and 5-bromo-4-chloroindole exhibited the strongest antifungal and antibiofilm effects, with minimum inhibitory concentration (MIC) values of 10–50 µg/mL, outperforming ketoconazole and comparable to miconazole. Both di-halogenated indoles markedly inhibited cell aggregation, yeast-to-hyphae transition, and induced reactive oxygen species (ROS) accumulation, contributing to fungicidal activity. Microscopic analyses revealed the disruption of hyphal networks and reduced biofilm biomass. They showed moderate cytotoxicity in human hepatocellular carcinoma (HepG2) cells (median lethal dose, LD₅₀ = 35.5 µg/mL and 75.3 µg/mL) and low phytotoxicity in plant assays. The quantitative structure–activity relationship (QSAR) model identified halogen substitution at C4, C5, and C6 positions as optimal for antifungal activity due to enhanced hydrophobic and electron-withdrawing effects. Together, these findings demonstrate that di-halogenated indoles serve as potent, low-toxicity inhibitors of Candida growth, biofilms, and morphogenesis, providing a promising scaffold for next-generation antifungal agents targeting drug-resistant Candida species. Full article

The increasing demand for sustainable chemical processes has fostered the development of advanced catalytic systems for biomass valorization. In this work, a series of mono-, bi-, and trimetallic oxides (FeO, FeCuO, FeZnO, and FeCuZnO) were successfully synthesized using MIL-101-based MOFs as sacrificial templates. The obtained materials were thoroughly characterized by N₂ adsorption–desorption, XRD, FTIR, and TEM/STEM-EDX to investigate their structural, morphological, and textural properties. Their catalytic performance was evaluated in the selective oxidation of benzyl alcohol, a lignin-derived platform molecule, into benzaldehyde under microwave irradiation as a sustainable heating strategy. The results demonstrate that MOF-derived oxides exhibit superior activity compared to their parent MOFs, highlighting the beneficial effect of thermal treatment on the exposure of active sites. Among the catalysts, heterometallic oxides showed enhanced performance due to synergistic effects between metals. In particular, FeZnO reached a maximum yield of 62.1% towards benzaldehyde at 150 °C and 30 min, outperforming the monometallic oxide. Recycling tests revealed that FeZnO retained higher overall performance than FeCuO, which suffered from progressive copper leaching. These findings confirm the potential of MOF-derived multimetallic oxides as efficient and reusable heterogeneous catalysts for selective biomass-derived alcohol oxidation. The combination of microwave-assisted processes and the tuneable nature of MOF-derived oxides provides a promising pathway for designing sustainable catalytic systems with industrial relevance. Full article

Lignocellulosic agricultural residues represent a rich source of potential feedstock for biorefinery applications, but their valorization remains challenging. The white-rot fungus Irpex lacteus J2 exhibited a promising degradation effect, but its molecular mechanisms of lignocellulose degradation remained largely uncharacterized. Here, we performed high-quality whole-genome sequencing and untargeted metabolomic profiling of I. lacteus J2 during the degradation of corn straw as the sole carbon source. The assembled I. lacteus J2 genome contained 14,647 protein-coding genes, revealing a rich genetic repertoire for biomass degradation and secondary metabolite synthesis. Comparative genomics showed high synteny (mean amino acid sequence identity 92.28%) with I. lacteus Irplac1. Untargeted metabolomic analysis unveiled a dynamic metabolic landscape during corn straw fermentation. Dominant metabolite classes included organic acids and derivatives (27.32%) and lipids and lipid-like molecules (25.40%), as well as heterocyclic compounds (20.41%). KEGG pathway-enrichment analysis highlighted significant activation of core metabolic pathways, with prominent enrichment in global metabolism (160 metabolites), amino acid metabolism (99 metabolites), carbohydrate metabolism (24 metabolites), and lipid metabolism (19 metabolites). Fermentation profiles at 3 and 15 days demonstrated substantial metabolic reprogramming, with up to 210 upregulated and 166 downregulated metabolites. Correlation analyses further revealed complex metabolic interdependencies and potential regulatory roles of key compounds. These integrated multi-omics insights significantly expand our understanding of the genetic basis and metabolic versatility, enabling I. lacteus J2 to efficiently utilize lignocellulose. Our findings position I. lacteus J2 as a robust model strain and provide a valuable foundation for developing advanced fungus-based strategies for sustainable bioprocessing and valorization of agricultural residues. Full article

Plant cell wall-derived oligosaccharides, such as xylo-oligosaccharides (XOS), serve as key signaling molecules regulating plant growth and immunity. The bioactivity of XOS is closely tied to their degree of polymerization (DP), yet the molecular mechanisms underlying DP-specific effects remain poorly understood. Here, we investigated the transcriptional and phenotypic responses of lettuce (Lactuca sativa) to foliar application of four high-purity XOS variants: xylobiose (XOSY, DP2), xylotriose (XOSB, DP3), xylotetraose (XOSD, DP4), and xylopentose (XOSW, DP5). Phenotypic analyses revealed that high-DP XOS (XOSD and XOSW) significantly enhanced aboveground biomass and root system development, with XOSD showing the most pronounced effects, including a 31.74% increase in leaf area and a 20.71% increase in aboveground biomass. Transcriptomic profiling identified extensive transcriptional reprogramming across treatments, with XOSD eliciting the highest number of differentially expressed genes (DEGs). Functional enrichment analyses indicated that XOSD and XOSW upregulated genes involved in plant hormone signaling, starch and sucrose metabolism, and cell wall biosynthesis, while downregulating photosynthesis-related genes. Notably, MapMan and KEGG pathway analyses revealed that XOSD significantly activated biotic stress-related pathways, including MAPK signaling, β-1,3-glucanase activity, and PR protein pathways. In contrast, XOSY treatment primarily upregulated genes linked to basal immunity, highlighting distinct mechanisms employed by low- and high-DP XOS. These findings demonstrate that XOS with varying DP differentially modulate growth- and immunity-related processes in lettuce. High-DP XOS, particularly XOSD, not only promote plant biomass accumulation but also enhance immune responses, highlighting their potential as biostimulants for sustainable agriculture. This study provides a molecular framework for understanding the DP-specific bioactivity of XOS and their dual role in optimizing plant growth and defense. Full article

With the rapid industrialization, excessive reliance on fossil fuels has resulted in energy crises and environmental pollution, driving the search for sustainable alternatives. Biomass-derived resources have emerged as promising candidates to replace fossil-based feedstocks. Among these, furfural (FF) serves as a key platform molecule that can be catalytically hydrogenated to various high-value chemicals, with furfuryl alcohol (FA) representing one of the most valuable products. Currently, Cr-based catalysts remain predominant for the selective hydrogenation of FF to FA. However, the severe environmental toxicity of Cr necessitates urgent development of alternative Cr-free catalytic systems. This study systematically reviews recent advances in FF hydrogenation to FA, providing an in-depth discussion of reaction mechanisms, including adsorption configurations, solvent effects, and side reactions, as well as a comprehensive analysis of structure–activity relationships, involving active metal, support, promoter, and preparation methods. Furthermore, we evaluate the application of the advanced characterization techniques for monitoring the reaction processes. Finally, we propose the future research directions: (1) designing efficient and stable non-noble metal catalysts and (2) elucidating reaction mechanisms via the combined in situ characterization and theoretical calculations. These efforts would facilitate the academic understanding and industrial implementation of the FF-to-FA conversion process. Full article

The terpeno-heterocyclic molecular hybrids are a new and promising class of modern organic and medicinal chemistry, because their molecules exhibit high and selective biological activity, natural origins, and good biocompatibility, and, usually, they are less toxic. The reported norlabdane-heterocyclic hybrids were synthesized by classical and new, original, and environmentally friendly methods, which include coupling reactions of norlabdane derivatives (such as carboxylic acids, acyl chlorides, or bromides) with individual heterocyclic compounds, as well as heterocyclization reactions of certain norlabdane intermediates like hydrazides, thiosemicarbazones, or hydrazinecarbothioamides. The aforementioned norlabdanes were derived from (+)-sclareolide 2, which is readily obtained from (−)-sclareol 1, a labdane-type diterpenoid extracted from the waste biomass of Clary sage (Salvia sclarea L.) that remains after essential oil extraction. All synthesized compounds were tested against various fungal strains and bacterial species, with many exhibiting significant antifungal and antibacterial activity. These findings support the potential application of the synthesized compounds in the treatment of diseases caused by fungi and bacteria. Additionally, the use of plant-based waste materials as starting resources highlights the economic and ecological value of this approach. This review summarizes experimental data on the synthesis and biological activity of norlabdane: diazine, 1,2,4-triazole and carbazole, 1,3,4-oxadiazole, 1,3,4-thiadiazole, 1,3-thiazole, 1,3-benzothiazole and 1,3-benzimidazole hybrids performed by our research group covering the period from 2013 to the present. Full article

As a model compound for lignin derivatives, anisole and its conversion are crucial for the upgrading of biomass resources. Anisole molecule contains a characteristic aryl ether bond (C_aryl-O-CH₃); therefore, the selective cleavage of the C-O bond to efficiently produce high-value chemicals poses a significant challenge. Constructing bimetallic synergistic active sites through tuning the metal-support interface is considered an effective strategy. In this work, the WO₃-promoted Pt/SiO₂ catalysts were investigated to enhance the performance of anisole hydrodeoxygenation (HDO) to hydrocarbons. Experimental results demonstrate that WO₃ significantly promotes HDO selectivity, increasing from 37.8% to 86.8% at 250 °C. Moreover, moderate doping improves low-temperature (<250 °C) HDO activity, confirming the presence of synergistic effects. In contrast, excessive WO₃ suppresses anisole conversion. Characterization results reveal that WO₃ stabilizes metallic Pt and facilitates H₂ dissociation. Concurrently, strong hydrogen spillover between Pt and WO₃ promotes oxygen vacancy formation on WO₃. This transforms disordered adsorption of anisole on SiO₂ into directed adsorption of the anisole’s oxygen species onto WO₃. This work achieves high anisole HDO selectivity through the Pt-WO₃ interface tuning, offering novel insights for efficient lignin conversion. Full article

Cellulose aerogel is a promising thermal insulation material with terrific thermal insulation and environmental friendliness. However, the intrinsic flammability of polysaccharide molecules and dependence on freeze-drying have limited its application in flame-retardant and thermal management systems. Here, we develop a flame-retardant biomass aerogel based on a dual-network matrix of bacterial cellulose and sodium alginate. This innovative material enables high-efficiency and low-cost preparation via ambient pressure drying technology (only ~3.5% volume shrinkage), while achieving flame retardancy by introducing an inorganic nanosheet microstructure within a polymer matrix. The resulting dual-network flame-retardant cellulose aerogel demonstrates thermal performance superior to that of most polymer foams and conventional cellulose aerogels, featuring an ultra-low thermal conductivity of ~0.04 W m⁻¹ K⁻¹ and a high limiting oxygen index (LOI) of ~69%. This research provides a novel strategy for simultaneous flame-retardant modification and energy-efficient manufacturing of biomass-derived aerogels. Full article

The global depletion of fossil resources, combined with accelerating climate change and environmental concerns, is driving intensive research into alternative, sustainable sources of energy and raw materials. Particular attention is being paid to lignocellulosic biomass as the most abundant and renewable organic resource. The catalytic conversion of biomass-derived carbohydrates into high-value-added products (fuels and chemicals) aligns with the principles of sustainable development and offers a viable alternative to petroleum-based feedstocks. This review provides a product-oriented perspective on the deep valorization of carbohydrates, focusing on catalytic strategies that enable the production of renewable fuels and chemicals. It highlights two key stages in the valorization of lignocellulosic biomass: (1) the acid-catalyzed conversion of carbohydrates into platform molecules (furfural, 5-hydroxymethylfurfural, and levulinic acid); and (2) the selective hydrogenation and hydrogenolysis of these intermediates to obtain target end products. These target products fall into two major categories: (i) biofuels and fuel additives; and (ii) green chemicals, such as solvents, pharmaceuticals, agrochemicals, cosmetics, and intermediates for the synthesis of biobased polymeric materials, including polyesters, resins, and polyurethanes. Particular emphasis is placed on recent advances in the development of heterogeneous catalysts. Solid acid catalysts used in the synthesis of platform molecules are discussed, along with ruthenium-based catalysts employed in the subsequent hydrogenation and hydrogenolysis steps. Recent efforts toward integrating both catalytic stages into a single one-pot processes using bifunctional metal–acid catalysts and dual catalytic systems based on ruthenium are also reviewed, as they represent a promising route to simplify biomass valorization schemes and improve product selectivity toward fuels and chemicals. Full article

Nitrogen dioxide (NO₂) plays a crucial role in environmental processes and public health. In recent years, NO₂ pollution has been monitored using a combination of in situ measurements and satellite remote sensing, supported by the development of advanced retrieval algorithms. With advancements in satellite technology, large-scale NO₂ monitoring is now feasible through instruments such as GOME-2C and TROPOMI. However, the fixed local overpass times of polar-orbiting satellites limit their ability to capture the complete diurnal cycle of NO₂, introducing uncertainties in emission estimation and pollution trend analysis. In this study, we evaluated differences in NO₂ observations between GOME-2C (morning overpass at ~09:30 LT) and TROPOMI (afternoon overpass at ~13:30 LT) across three representative regions—East Asia, Central Africa, and Europe—that exhibit distinct emission sources and atmospheric conditions. By comparing satellite-derived tropospheric NO₂ column densities with ground-based measurements from the Pandora network, we analyzed spatial distribution patterns and seasonal variability in NO₂ concentrations. Our results show that East Asia experiences the highest NO₂ concentrations in densely populated urban and industrial areas. During winter, lower boundary layer heights and weakened photolysis processes lead to stronger accumulation of NO₂ in the morning. In Central Africa, where biomass burning is the dominant emission source, afternoon fire activity is significantly higher, resulting in a substantial difference (1.01 × 10¹⁶ molecules/cm²) between GOME-2C and TROPOMI observations. Over Europe, NO₂ pollution is primarily concentrated in Western Europe and along the Mediterranean coast, with seasonal peaks in winter. In high-latitude regions, weaker solar radiation limits the photochemical removal of NO₂, causing concentrations to continue rising into the afternoon. These findings demonstrate that differences in polar-orbiting satellite overpass times can significantly affect the interpretation of daily NO₂ variability, especially in regions with strong diurnal emissions or meteorological patterns. This study highlights the observational limitations of fixed-time satellites and offers an important reference for the future development of geostationary satellite missions, contributing to improved strategies for NO₂ pollution monitoring and control. Full article