Viticulture produces large amounts of grape canes during annual pruning, most of which remain underexploited or are disposed of burned, raising environmental concerns. These residues, however, constitute a valuable feedstock for sustainable valorization strategies. This review provides a comprehensive and critical appraisal of grape canes within a circular bioeconomy framework by linking high-value phenolic compound extraction with energy and environmental applications in a cascade approach. The first section synthesizes current knowledge on phenolic acids, flavonoids and stilbenes, highlighting the key factors influencing their variability (cultivar, environmental conditions, extraction parameters) and identifying the most promising application domains in enology, food preservation, nutraceuticals, cosmetics, and biocontrol. The second section critically examines the valorization of post-extraction lignocellulosic residues through thermochemical conversion, biofuel production, and activated carbon and biochar generation, discussing energetic performance, environmental benefits, and scalability challenges. By integrating biochemical and thermochemical pathways, this review identifies current research gaps, technological bottlenecks, and opportunities for industrial implementation. Grape canes emerge as a multifunctional agricultural by-product with strong potential to contribute to resource efficiency, waste minimization, and sustainable bioeconomy development.

This study reveals temperature-dependent pathways in the regeneration of keratin from duck feathers via ultrasound-assisted alkaline hydrolysis, establishing direct links between molecular transformations and resulting material morphologies. By systematically varying the hydrolysis temperature from 25 degrees C to 85 degrees C, we identify a critical threshold around 55 degrees C that governs keratin's unfolding and refolding behavior. At lower temperatures (<= 55 degrees C), keratin retains its native disulfide linkages and regenerates into fibrous structures resembling feather morphology. Above this threshold, extensive cleavage and reformation of disulfide bonds induce supramolecular reorganization, yielding uniform keratin microspheres with enhanced thermal stability and distinct Raman signatures. Comprehensive characterization (ATR-IR, Raman, solid-state NMR, XRD, SEM, TGA, DSC) provides unprecedented insights into how temperature and sonochemical activation modulate protein structure at both molecular and mesoscopic scales. These findings establish a chemistry-based design principle for tailoring keratin into functional biomaterials with tunable properties, enabling scalable and sustainable approaches to bioplastics, composites, and biointerfaces.

This study explores the potential of ultrasound-assisted alkaline hydrolysis, employing a cup horn sonoreactor, for the sustainable extraction of keratin from duck feather waste. Unprecedented in its approach, this research evaluates the system's efficacy in maintaining the structural integrity of cystine-a crucial amino acid-through controlled hydrolysis processes, or promoting disulfide bond rupture and regeneration upon precipitation. By using the unique advantages of the cup horn system, including homogeneous energy distribution and gentle processing, this investigation aims to overcome the limitations of hydrothermal treatments. The obtained keratins were analyzed using advanced spectroscopic, microscopic, and thermal analysis techniques (ATR-IR, Raman, SDS-PAGE, SEM, 13C CP-MAS NMR, XRD, and TGA). These analyses allowed the unveiling of the reaction pathways and structural changes in keratin under various temperatures in alkaline conditions. Lower temperatures (35 °C) favored the preservation of native disulfide linkages, while higher temperatures (75 °C) enhanced disulfide bond rupture and reformation. An intermediate temperature (55-65 °C) offered a balance between structural integrity and yield. This innovative method represents a significant advancement in feather waste valorization, providing a scalable and adaptable platform to tailor keratin properties such as yield, thermal stability, or disulfide bond regeneration, according to specific application needs.

This Feature Article reviews recent advances in green chemistry, with a focus on scaling up both conceptually and industrially. We particularly discuss the contributions to circular economy principles through solvent replacement, non-conventional activation technologies, and the valorization of waste and biomass. The article also outlines strategies to transition lab-scale innovations into widespread and impactful industrial applications, highlighting opportunities and challenges associated with this transition.

Apple pomace (AP), a by-product of the apple juice and cider industries, represents a significant waste challenge, generating approximately 5 million tons produced worldwide in 2021. Often disposed of in landfills, AP contributes to health and environmental risks. Despite its disposal, AP remains a valuable source of bioactive compounds, recognized for their biological properties. This study assesses the carbon footprint associated with extracting these bioactive compounds using innovative technologies, namely supercritical CO2 (SC-CO2) and subcritical water extraction (SWE). Utilizing SimaPro software and the ecoinvent database, the Life Cycle Assessments (LCA; cradle-to-gate) were conducted for extracting 1 g of bioactive compounds from AP. The findings reveal that the SC-CO2 process emits 71.42 kgCO2eq, while the SWE results in significantly lower emissions of 6.20 kgCO2eq. These results highlight the environmental impact of different extraction technologies and emphasize the potential for more sustainable practices in valorizing AP. This study highlights the importance of conducting Life Cycle Assessments (LCAs) for sustainable technologies, offering critical insights that can inform future industrial practices and policy decisions. Furthermore, the findings indicate that a technology labeled as 'green' is not necessarily environmentally superior, prompting a reconsideration of current sustainability definitions.

The aim of this study was to evaluate the antioxidant and antibacterial properties of apple pomace (AP) extracts using natural deep eutectic solvents (NADES). Six NADES, based on choline chloride (ChCl), were used as environmentally friendly solvents. Four of these were combined with organic acids, while the other two were combined with urea; they were then used to extract bioactive compounds from AP. ChCl:urea mixture proved to be the solvent with the highest total polyphenol content (TPC), with 13.15 +/- 4.70 mg gallic acid equivalent/mL. Antioxidant activity and total anthocyanidin content (TAC) were also assessed. ChCl:oxalic acid recorded the highest values with 35.59 +/- 9.53 mg extract/mL and 64.81 +/- 4.65 malvidin-3-glucose equivalent mu g/mL, respectively. Solvent pH plays a crucial role in selective extraction; an acidic pH facilitates selective anthocyanidin extraction, while a basic pH does not. Anthocyanidin extraction correlated with extract antioxidant activity and solvent viscosity. In addition, the antibacterial activity of the extracts against Bacillus cereus, Listeria innocua, and Escherichia coli strains was studied. All extracts showed antibacterial properties against the strains tested. The ChCl:oxalic acid extracts showed particularly low minimum inhibitory concentrations (e.g., 25 mgextract/mL for B. cereus) and EC50 values (e.g., 6.0 +/- 0.3 mgextract/mL for B. cereus).

Spent coffee grounds (SCGs) are a major global waste, yet rich in valuable bioactive compounds. Unlocking their potential requires advanced analytical techniques due to the complexity of their molecular composition. This study presents an innovative RPLC × SFC-HRMS method-an online two-dimensional liquid chromatography approach-for simultaneous analysis of sterol and diterpene derivatives in SCGs. Using a custom-built interface, both free and esterified lipid fractions were analyzed directly from intact, non-saponified and non-derivatized extracts. The method effectively resolved isomeric compounds and sterol oxidation products, highlighting its power for comprehensive lipid profiling and paving the way for SCG valorization in health-focused applications.

Terephthalic acid (H2TPA) solubility in several ionic liquids (ILs) at multiple concentrations is higher than for any other known solvents at lower temperatures and pressures which suggests low energy purification of H2TPA from its major impurity, 4-carboxybenzaldehyde (4-CBA) might be possible. To understand the mechanism several strategies were explored to purify H2TPA by taking advantage of this high solubilizing power of ILs for H2TPA in the crystallization of unique salts and cocrystals. Using either zwitterionic carboxylate IL-precursors or direct salt formation with carboxylate ILs or amines, a series of salts of mono, dibasic and two ionic cocrystals were obtained including monobasic, [C1C1im][HTPA], [N4441][HTPA], [C4C1im][HTPA]•0.5H2TPA (a cocrystal), and [C1Him][HTPA] ([C1C1im]+ = 1,3-dimethylimidazolium, [N4441]+ = tribuytlmethylammonium, [C1Him]+ = 1-methyl-3-H-imidazolium), dibasic [C1C1im]2[TPA], [C4C1im]2[TPA], [N4444]2[TPA], [C1Him]2[TPA], [H2N22]2[TPA], [H3N6]2[TPA], and [HN(CH2CH2OH)3]2[TPA] ([C4C1im]+ = 1-butyl-3-methylimidazolium, [N4444]+ = tetrabuylammonium, [H3N6]+ = hexylammonium, [HN(CH2CH2OH)3]+ = triethanolammonium, [H2N22]+= diethylammonium), and a second cocrystal [C2C1im]Cl•0.5H2TPA. The formation of these salts suggest a viable method to purify H2TPA because of preferred salt formation at low energy conditions. One elegant route using 1-ethyl-3-methylimidazolium chloride ([C2C1im]Cl) could be especially promising because the cocrystal [C2C1im]Cl•0.5H2TPA was readily isolated and is easily dissociated when exposed to ambient conditions into crystalline H2TPA and a liquid of hydrated [C2C1im]Cl.

Feathers, as a byproduct of the poultry industry, present a significant source of keratinous waste. Conventional methods have been widely used to extract keratin from feathers; however, they are associated with limitations such as high operational costs and environmental concerns. It is, therefore, crucial to develop cost-effective and time-efficient methods for extracting keratin on a large scale. In recent years, ultrasound-assisted alkaline hydrolysis has emerged as a promising and sustainable approach for efficient keratin recovery. This study compares the hydrolysis time, yield, and chemical properties of keratin extracted from feathers using ultrasound-assisted alkaline hydrolysis and thermal alkaline hydrolysis (hot plate method). The influence of factors such as particle size, alkali concentration, liquid-to-solid ratio, reactor geometry, temperature of keratin colloid upon precipitation, precipitation pH, and precipitating acid was investigated. Favorable conditions for ultrasound-assisted alkaline hydrolysis were found to be 3% NaOH, a 10:100 (w/v) solid-to-liquid ratio, using a cylindrical vessel, and an ultrasonic energy density of 360 kJ/L, with pH adjustment to 4.5 using citric acid after cooling to room temperature. This method outperformed the thermal approach, yielding 70% keratin in 25 min, compared to 23% in 90 min using a hot plate, due to the exothermic effect of cavitation. The results provide valuable insights into the potential of ultrasound-assisted alkaline hydrolysis as an eco-friendly and cost-effective approach to address the management of keratinous waste and enhance the overall recovery of keratin.

This review focuses on the utilization of apple waste for antimicrobial applications, aiming to enhance its value. The use of sub- and supercritical fluids for extracting biological molecules is emphasized as a promising eco-extraction technology. The study highlights the significant antimicrobial activities observed in the extracts obtained from apple waste. Furthermore, the influence of extraction and storage conditions on the chemical profile and biological activity of these extracts is discussed. Supercritical CO2 extraction was found to produce higher quality extracts compared to conventional methods, primarily due to the absence of air and light. To maintain the chemical and biological properties of the extracts, it is crucial to carefully control the pretreatments, drying processes, and storage conditions of the apple waste. Lastly, this review explores the potential enhancement of biological activities through physicochemical functionalization methods.

Ambrosia artemisiifolia and Solidago canadensis are invasive plants with adverse ecological, socio-economic, and health impacts. After management operations, the plant waste can represent a definite opportunity for the circular economy. To that end, an evaluation of their chemical compositions using UHPLC-MS was carried out. We also investigated their antioxidant capacities (DPPH center dot, ABTS center dot+, CUPRAC, FRAP and iron chelation) and, for the first time, their anti-lipase properties using capillary electrophoresis. The extracts mainly contained two compounds: 5-O-caffeoylquinic acid and 3,5-dicafeoylquinic acids. Notably, S. canadensis is characterized by the presence of two additional compounds, 3,4-dicaffeoylquinic and 4,5-dicaffeoylquinic acids, which are abundant in its roots, as well as quercitrin in its aerial parts. The findings revealed significant antioxidant capacities. Specifically, with the DPPH center dot assay, the aerial part of S. canadensis exhibited stronger antioxidant activity than that of A. artemisiifolia at every tested concentration. At 50 mu g/mL, the percentages of inhibition DPPH center dot were 24.3 +/- 3.2% and 56.7 +/- 3.4% respectively. At the same concentration, the root parts were marginally less active than the aerial parts. By HPTLC-DPPH, the main antioxidant markers were highlighted. S. canadensis was a better anti-lipase agent than A. artemisiifolia with enzymatic inhibition percentages of 82.3 +/- 0.2% and 49.6 +/- 5.9% respectively (at 100 mu g/mL). The two acids present in all the crude extracts were tested separately as pancreatic lipase inhibitors. In conclusion, these plants could potentially be utilized for mitigating various pathologies arising from oxidative stress, including obesity.

La sonochimie, basée sur l’utilisation des ultrasons de puissances et le phénomène de cavitation acoustique, représente un potentiel important comme technologie de rupture pour diverses applications en chimie. Les exemples sont nombreux en catalyse, en préparation de matériaux, en synthèse ou en dégradation de polymères.