IntroductionIntensive livestock farming has sparked public debate, highlighting the need for sustainable livestock production. One effective strategy to improve both environmental sustainability and meat quality is the inclusion of agro-industrial byproducts in pig diets. This study aimed to investigate the effects of dietary inclusion of hazelnut skin (HS) or its green polyphenolic extract (HSE) on growth performance, carcass traits, and meat quality in heavy pigs.MethodsSeventy-two pigs were allotted to three dietary treatments (n = 24 each): a control group (C) fed a standard diet, and two experimental groups receiving the same diet, including either 0.6% HS replacing 0.6% of wheat bran (HSD) or adding 0.1% HSE (HSED). After growth performance assessment, 36 subjects, balanced by gender and treatment, were slaughtered for carcass and meat quality evaluations.ResultsNo differences were observed in growth performance or carcass yield, indicating all diets met nutritional needs. However, HSE supplementation increased thigh yield (p < 0.01). Overall, meat quality characteristics did not differ among treatments; however, HS inclusion showed positive trends in oxidative stability during cooking, n-3 polyunsaturated fatty acid content, and the n-6/n-3 ratio. HSE supplementation decreased cooking loss, giving it better water-holding capacity. The treated groups showed a reduction in cholesterol content in the meat of 7.56 and 12.10% in the HSD and HSED groups, respectively.ConclusionOverall, the modest yet positive effects, combined with the absence of negative influences on growth performance, carcass traits, and meat quality, indicate that HS and HSE supplementation could offer commercial and environmental benefits in sustainable livestock systems.

The valorization of lignocellulosic biomass represents a key strategy for the sustainable production of platform chemicals without food resources.. Amonf these, furfural is a pivotal C5 building block with applicationsin biofuels, fine chemicals, and pharmaceuticals. In this study, we report a direct and efficient conversion of raw wheat straw to furfural using a natural deep eutectic solvent (NaDES) under mild microwave-assisted conditions, without any preliminary biomass pretreatment.wheat straw to furfural using a natural deep eutectic solvent (NaDES) under mild microwave-assisted conditions, without any preliminary biomass pretreatment.A choline chloride/oxalic acid (1:1) NaDES enabled the selective transformation of the hemicellulosic fraction, affording furfural with >99% selectivity and no detectable HMF formation, as confirmed by GC–MS analysis. The process operates at low temperature (80 °C) and short reaction times, and allows straightforward product separation through cooling and centrifugation. Scale-up experiments demonstrated the robustness and reproducibility of the protocol, with furfural yields up to 20 wt% from untreated straw and 27 wt% from delignified biomass.Importantly, residual furfural remaining in the aqueous phase was further valorized in situ into bi-functionalized cyclopentenones, enabling complete utilization of the produced platform molecule and reinforcing the circular nature of the process. Overall, this work presents a NaDES-based platform for the selective C5 valorization of lignocellulosic biomass, combining process intensification, high selectivity, and circular economy principles.

Agro-industrial lignocellulosic wastes represent a huge source of biopolymers, proteins, carbohydrates, and active compounds. Their fractionation through eco-friendly routes is a challenge in accessing the components of interest while minimizing environmental impacts. In this study, a 20-min microwave-assisted subcritical water extraction (MASWE) was selected to isolate cellulose from soybean hulls. This emerging green hydrothermal process, coupled with a microwave-assisted alkaline (MW-NaOH) treatment, enabled the reduction of harsh chemical employment compared to classical biomass fractionation, ensuring, at the same time, a high cellulose enrichment of up to 91.5% in the best procedure. The environmental impacts of the up-scaled optimized strategy were compared to those of the multi-hydrolysis treatment through a life-cycle assessment analysis. The MW-based cellulose extraction provides clear advantages in toxicity-related categories, but it is still necessary to reduce the energy-driven impacts.

Herein, a study on the deoxygenation of substituted aromatic ketones over commercial Pd/Al2O3 (5 wt %) is reported. The reaction occurs under very mild conditions (120 °C, 5 bar H2) in just 2 h using microwaves to enhance the kinetics. Ethanol was found to be the best solvent, while the effect of the substituents was studied over different substrates. On the basis of experimental evidence, a mechanism is proposed in which keto-enol tautomerization enables deoxygenation to the corresponding alcohol followed by direct hydrogenolysis to the alkyl chain.

AIMS:This work aims (i) to evaluate in vitro the antibacterial and antibiofilm activities of an extract collected from a hazelnut by-product (skins) against spoilage bacteria and foodborne pathogens and (ii) to assess its effects on the microbiological quality and sensory/technological characteristics of beef burgers. METHODS AND RESULTS:The antibacterial properties of hazelnut skin extract (HSE) at concentrations ranging from 2.5 to 20 mg mL-1 were evaluated using a modified protocol based on the method described by the Clinical and Laboratory Standards Institute. In parallel, the biofilm-eradicating potential was assessed according to the Innovotech guidelines, which describe a standardized method for biofilm disruption studies. In vivo experiments were also conducted on beef burgers containing 2% and 4% HSE, along with untreated controls. Each sample underwent microbiological and physicochemical analyses at 0, 3, and 6 days of refrigerated storage.During in vitro assays, HSE exhibited greater antibacterial activity against Gram-positive bacteria, with growth inhibition occurring at lower concentrations. Conversely, in vivo tests revealed no statistically significant differences in microbiological parameters between control and HSE-treated burgers. Furthermore, adding different concentrations of HSE to the treated samples did not significantly affect the pH, although it altered the acidification dynamics, which occurred earlier on day 3 in burgers containing 4% HSE. Finally, both concentrations of HSE resulted in significant differences in weight loss and color. CONCLUSIONS:In light of these findings, further studies are required to enhance HSE bioavailability in food matrices and to minimize its impact on their sensory/technological properties.

Cocoa bean shells (CBS) represent a significant by-product of the transformation of cocoa beans, constituting approximately 15% of the total cocoa bean weight. Recently, interest in exploring the potential of these shells as a sustainable source of functional ingredients for use in cosmetics and nutraceuticals has grown. The present study investigates microwave-assisted subcritical water extraction (MASWE) as a green and fast technique to recover bioactive compounds from CBS. A flash extraction (five minutes) at 170 degrees C yielded a maximum of 45.78 mg of gallic acid equivalents (GAE) per gram of CBS, which was higher than that obtained using conventional conditions (25.73 mg GAE/g CBS with 50% acetone solution). Additionally, the HPLC profile of the extract from MASWE revealed a significant increase in hydroxybenzoic acids and catechin, compared to the conventional extract. Following the optimization of the extraction process, seven distinct resins were examined to isolate a bioactive-enriched fraction: Sepabeads SP700 was found to be the most effective resin for concentrating such compounds, increasing both methylxanthines and TPC selectivity up to 4.2-fold. This valorization approach, integrating MASWE and downstream optimization, offers an innovative strategy to recover added-value products from CBS in line with green extraction and nutraceutical innovation.

ZnO can be easily obtained using different salts as precursors, and many examples are present in the literature describing the effect of several additives in the synthesis. In this paper, we study the effects of the addition of polyphenols present in the residues of the wine supply chain. The polyphenols are extracted from grape pomace and fractionated, exploiting a membrane-based process equipped with polysulfone ultrafiltration membranes (cut-off 1 kDa and 5 kDa) that can separate the plethora of molecules into larger than 5 kDa and smaller than 1 kDa. The extract and its fractions after the ultrafiltration process were used as additives for the thermal precipitation synthesis of ZnO from Zn acetate. The chemical and physical properties were studied with the aim of understanding the characteristics that influence the activity of the photocatalysts. To this purpose, a commercial system was used for comparison, and the photoactivity was analyzed with a caffeine solution upon irradiation, exploiting the UVA and VIS electromagnetic radiation for the activation of the catalytic materials. The kind of polyphenol fraction affects the surface behaviors of the nanoparticles. Morphology, presence of trapped hole/electron centers, and acidity/basicity of the surface sites of ZnO appear to be the most relevant features in the efficiency towards caffeine degradation.

The increasing demand for sustainable chemical processes has driven the search for renewable feedstocks, environmentally benign catalysts, and energy-efficient methodologies. In this context, we report a solvent-free protocol for the Claisen-Schmidt condensation between biomass-derived furanic aldehydes and acetophenone. Commercial magnesium oxide (MgO) was employed as a recyclable heterogeneous catalyst and subjected to physicochemical characterization and recycling tests to evaluate its stability and reusability. Microwave (MW) irradiation was integrated to ensure rapid and homogeneous heating, leading to enhanced reaction efficiency and reduced processing times. The sustainability of the proposed approach was preliminarily assessed through green chemistry metrics, which confirmed its advantages over conventional methods. The obtained furano-chalcones were investigated for their antiviral potential in in vitro cell-based models against common human pathogenic viruses, such as human herpes simplex virus, Zika virus, rhinovirus and influenza virus. Their activity was specifically targeted against HSV type 2, highlighting their relevance as pharmacologically active scaffolds and warranting further optimization and investigation. Overall, this work combines renewable resources, recyclable catalysis, and energy-efficient techniques, offering a greener and versatile strategy for the synthesis of high-value bioactive compounds.

Lignocellulosic biomasses have the potential to generate by-products with biological activity (i. e., polyphenols) as well as biopolymers (i. e., cellulose, hemicellulose, pectins, lignin). The wine industry is one of the pillars of Italian agri-food sector. Nevertheless, large quantities of by-products such as grape stems are produced, which are usually disposed of at a cost, and therefore represent an attractive negative-cost feedstock for biorefinery. In this work, a sequential protocol for biomass valorization is proposed, characterized by a multidisciplinary strategy using enabling technologies and subcritical water as a green solvent, where physical/chemical treatments synergistically interact with biological treatments. The first phase involved the sequential fractionation of grape stalks, obtaining several product streams rich in polyphenols, hemicellulose, pectin (13.15 % of cumulative yield on biomass), lignin and cellulose. A membrane treatment was employed to recycle materials within the process. Finally, the cellulose-rich residue was exploited as a fermentation substrate for the last step, producing up to 5.8 g/L of lactic acid by harnessing suitably engineered Clostridium thermocellum strains. The polyphenolic fraction successfully inhibited the growth of Brettanomyces bruxellensis and Acetobacter pasteurianus , microorganisms responsible for major wine off-flavors. Globally, this study represents a proof-of-concept of a second-generation biorefining process based on locally available waste biomass.

Hazelnut skins (HS), by-products of the hazelnut industry classified as waste, are rich in polyphenols, poli-unsaturated fatty acids and fibres. This study aimed at assessing the in vivo effects of HS inclusion in beef cattle diets. Eighty beef bulls were divided in two groups (control and test; 4 replicates per group), following a two-phase dietary plan (fattening – 5 months; finishing – 2 months). Both groups received forage (hay/straw) and feed, with the test feed presenting an 8% HS inclusion. Feeds’ chemical composition and total phenolic contents were assessed. Bulls’ in vivo growth performances were recorded, and haematological analysis were conducted at trial start and on slaughter day. Test feeds of both phases presented higher values (p < 0.001) of polyphenols than the control ones. No differences were observed in haematological or growth parameters during the fattening phase. In the finishing, the control group exhibited a lower (p < 0.05) feed conversion ratio than the test. However, the potential health benefits linked to the HS’ phenolic compounds, along with the re-valorization of an agro-industrial by-product and the resulting reduction in food waste, support the hypothesis that including HS in beef cattle diets may constitute a viable and sustainable strategy for the beef industry.

Commercial Rh/C and lab-made Rh/CNTs catalysts were compared in the one-pot microwave-assisted hydroaminomethylation of olefins to amines using EtOAc as the solvent. This reaction accounts for two steps: hydroformylation from the alkene, followed by aldehyde reductive amination. Acid sites exposed at the surface of the support promote the formation of a metal-alkene coordination complex to preferentially form the linear aldehyde. Synthetic and natural olefins were converted with yields up to 99% under mild conditions (120 degrees C, 40 bar of syngas, 4 h). With the addition of catalytic amounts of acetic acid, the hydroformylation step proceeded with a 99% yield over both catalysts. The catalysts were recovered and reused, maintaining their activity for three reaction cycles (12 h). The hydroaminomethylation step again gave yields up to 99%, using 1-hexene as substrate (120 degrees C, 4 h, 40 bar of N2/H2 1:1). Subsequent tests with different nitrogen sources resulted in amine yields ranging from 56% to 99%, even with ammonia. FESEM, XRD, and XPS were employed for an exhaustive surface characterization and structure-to-activity correlation of the catalysts.

The extraction of grape seed oil (GSO) for food and cosmetic applications was performed with 2-methyloxolane (2-MeOx) as a green solvent. The oil extraction yield, the tocopherol and tocotrienol content, the fatty acid and polyphenol profiles of the oils were analysed and compared with hexane. The entire extraction process, including the oil chemical refining, was further investigated on a pilot scale (15-litre extractor). Oil refining had a negative effect on the micronutrient content. The content of sterols, tocols and polyphenols was reduced by 19.78%, 47.6 % and 99% respectively. High amounts of polyphenols were recovered in refining by-products, with approximately 80% found in gums and 10% in soap-stock. The polyphenols contained in the crude oil and gums demonstrated effective intracellular ROS inhibition in HaCaT keratinocytes and BJ fibroblasts, as well as an antimelanogenic effect on B16-F10 murine melanoma cells. Consequently, these products are proposed as valuable cosmetic ingredients for treating hyperpigmentation disorders. In conclusion, 2-MeOx is an excellent alternative to hexane for GSO extraction, offering high extraction efficiency, a safer toxicological profile, and the production of oil and byproducts with promising food and cosmetic applications.

This study aimed to assess the impact of a 15-d administration of a polyphenol-rich extract from hazelnut skin (HS) on the incidence of neonatal calf diarrhea (NCD) and bronchopneumonia (BP) in Holstein heifers. Additionally, the study investigated whether the extract influenced blood derivatives of reactive oxygen metabolites (d-ROM), serum antioxidant capacity, fecal microbiota, growth rates, and severity of BP and NCD-related clinical parameters. In this randomized clinical trial, 80 healthy female dairy calves were allocated into 2 groups: a control group (CTRL, n = 40) and an HS-supplemented group (HS, n = 40), which received a milk replacer enriched with HS extract (5 g/d) from d 3 to d 18 of life. Daily clinical examinations were conducted for all calves until they reached 21 d of age. Additionally, thoracic ultrasonography (TUS) was performed at 21, 40, and 60 d of age, and weights were recorded at enrollment (d 3), 21 d, and 60 d. These repeated outcomes were analyzed using generalized estimating equations. Blood samples were collected from each calf at the beginning of the study and after HS (or control) administration for the evaluation of serum antioxidant capacity using the oxygen adsorbent test (OXY-Adsorbent) and for determining d-ROM. Additionally, rectal swabs were taken from all calves at 2, 10, 18, and 24 d of life for the analysis of fecal microbiota. The duration of diarrhea in the CTRL group was 22% higher than in HS (incidence rate ratio = 1.22; 95% CI: 1.03-1.45). Calves in the CTRL group had higher odds of elevated fecal scores (odds ratio = 1.23; 95% CI: 1.02-1.52). At 21 d of life, median OXY-Adsorbent values were 397.29 µmol (25th percentile [25°P] = 360.51; 75th percentile [75°P] = 426.30) in CTRL and 440.40 µmol (25°P: 400.97; 75°P: 479.14) in HS, with a significant difference between groups The ADG, fecal microbiota, d-ROM, BP, disease incidence, and all clinical parameters evaluated were not affected by HS administration. In conclusion, these findings suggest that the administration of HS resulted in a reduction in the duration of watery feces during NCD episodes and an improvement in serum antioxidant capacity in treated calves. However, HS supplementation did not demonstrate any effects on the overall clinical health issues associated with NCD, lung lesions identified via TUS, or weight gain. Future research on HS supplementation in calves should be conducted over a more extended administration period and include comprehensive cost-benefit analyses.

Squalene (SQE) is a key triterpene used in pharmaceuticals, nutraceuticals and cosmetics. Although olive pomace (OP) is a sustainable source of SQE, conventional hexane extraction raises environmental and health concerns. This study investigates the potential of 2-methyltetrahydrofuran (2-MeTHF) as a greener alternative for SQE extraction and catalytic hydrogenation to squalane (SQA); a high-value compound in industrial applications. 2-MeTHF provided 83% SQE recovery from OP, which was further concentrated in deodorizer distillates during refining. SQE hydrogenation in 2-MeTHF significantly improved reaction efficiency at lower temperatures (60 °C, 3 bar H2, 0.5 mol % Pd/C), enabling full conversion within 1 h. This represents a major advantage over conventional industrial hydrogenation, which requires harsher conditions (200 °C, 4-30 bar H2) and longer reaction times (6-7 h). In order to assess industrial feasibility, SQE from OP deodorizer distillates (6.8 wt %) was concentrated via saponification and molecular distillation (∼34 wt %), followed by flash chromatography (59 wt % purity, 85% recovery). However, residual impurities caused catalyst poisoning, lowering the SQA yield to 19.8%. This study highlights 2-MeTHF's potential for industrial-scale SQE valorization via integrated extraction and hydrogenation. Future efforts should focus on improving SQE purification from OP-DDs and enhancing catalyst recyclability.

Baeyer-Villiger monooxygenases (BVMOs) are versatile biocatalysts that catalyse the oxidation of ketones to esters with high regio- and enantioselectivity, operating under mild reaction conditions while reducing hazardous waste. Some BVMOs can convert cellulose-derived alkyl levulinates to 3-acetoxypropionates (3-APs), which are key intermediates in the production of 3-hydroxypropionic acid (3-HP), a versatile building block chemical. In this study, a BVMO from Acinetobacter radioresistens (Ar-BVMO) was tested as a biocatalyst for the conversion of three marketed alkyl levulinates: methyl, ethyl and butyl levulinate. The enzyme showed 4-fold higher catalytic efficiency (kcat/KM) and enhanced regioselectivity for the desired 3-AP product (4:1 ratio) when using butyl levulinate as a substrate. Escherichia coli whole-cells over-expressing Ar-BVMO were exploited to increase the product yield, achieving 85% conversion in 9 h. To further improve the sustainability of this biotransformation, butyl levulinate was obtained via microwave-assisted alcoholysis of pulp, a renewable cellulose feedstock, achieving 92.7% selectivity. Despite challenges posed by poor solubility of the resulting mixture in aqueous environment, Ar-BVMO in cell lysates was able to fully convert butyl levulinate within 24 h, efficiently producing 3-HP precursors without additional purification steps. These findings highlight the feasibility of this chemoenzymatic approach to convert cellulose-based raw materials to platform chemicals.

The Special Issue “Unlocking the Potential of Agri-Food Waste for Innovative Applications and Bio-Based Materials” brings together recent advances and emerging strategies for the valorization of agri-food residues. This Editorial provides an overview of the contributions included in the Special Issue, highlighting innovative approaches that convert waste streams into valuable bio-based materials, chemicals, and products. The collected works demonstrate how hydrodynamic, chemical, biological, and catalytic processes can be integrated to achieve sustainable waste management and circular resource recovery. By summarizing the main findings and perspectives, this Editorial emphasizes the growing relevance of agri-food waste valorization within the framework of the circular bioeconomy and encourages further interdisciplinary collaboration to accelerate the transition toward sustainable production systems.

Given the increasing consumer focus on healthier and environmentally friendly foods, the use of natural antioxidants in food production is becoming more common. The recovery of these antioxidants from agri-food waste is crucial for a circular economy, as it revalues matrices that would otherwise become waste. This study aimed to assess the antioxidant capacity of hazelnut skin and its green polyphenolic extract and to evaluate their effect on some qualitative parameters of pork burgers. Three types of burgers were formulated: a control group, and two experimental groups with the addition of 2.5 % of hazelnut skin or 1 % of hazelnut green extract. On days 0 and 7 of refrigerated storage (0-2 °C) parameters such as color, cooking losses, tenderness, lipid oxidation, and volatile profile were evaluated. Additionally, a group of panelists was asked to assess the acceptability of color and the potential for purchase. In both raw and cooked burgers, at all times examined, the two experimental groups showed a significant improvement in oxidative stability and lower production of volatile fat oxidation compounds compared to the control in which the main indicators of pork meat spoilage were detected. Although, even if on the 7th day of storage, the HS and HSE burgers exhibited better color stability, these groups showed a worsening in terms of color acceptability and tenderness. Overall, despite trade-offs, the hazelnut skin and their green extract showed high potential to emerge as food additives in meat products.

Grape stalks, an abundant byproduct of winemaking, are a promising source for nutraceutical applications due to their polyphenolic and pectic content. In this study, we evaluated the antioxidant and antimicrobial properties of grape stalk-derived polyphenols and the prebiotic potential of grape stalk-derived pectin. We assessed the antioxidant potential of polyphenol extracts through various in vitro tests (FRAP, TBARS, and metal chelation assays), finding significant reducing capacity, lipid peroxidation inhibition and metal chelation ability. Antimicrobial effects were also observed against probiotics, inhibiting Lactobacillus acidophilus CECT 1529 growth and biofilm formation, while Enterococcus faecium NCIMB 10415 exhibited reduced growth without biofilm disruption. In addition, we investigated the prebiotic potential of pectin extracts and its hydrolysates on the same probiotics E. faecium NCIMB 10415 and L. acidophilus CECT 1529. The hydrolysis significantly improved the availability of simple sugars, such as glucose and arabinose, thereby enhancing probiotic growth. Overall, pectin hydrolysate from ultrasonic treatment (PH-US) appeared to be the extract with the best prebiotic potential, providing an optimal balance of solubility and limited inorganic residues content. Our results underscore the potential of grape stalks as a cost-effective and sustainable source of antioxidants, antimicrobials, and prebiotics for the food and nutraceutical industries, supporting a circular economy approach.

Hazelnut skins (HS) are usually managed as waste; however, this by-product is a source of bioactive compounds, with potential applications in feed and food sectors. Phenolic compounds can be extracted using green protocols combining enabling technologies and green solvents. This work investigates subcritical water extraction (SWE) of bioactive compounds from HS. A laboratory-scale study was performed on four different batches, with significant batch-to-batch heterogeneity. The evaluation of polyphenolic profiles and antioxidant activities afforded promising results compared to the benchmark of reflux maceration. To evaluate process effectiveness, the extraction protocol was replicated on a semi-industrial plant that processed 8 kg of matrix. Downstream processes have been optimized for scale-up, demonstrating the effectiveness of SWE in retaining product concentration and bioactivity avoiding excipients in spray-drying phase. Hazelnut extracts exhibited antibacterial properties against animal- and food-borne pathogens, supporting their potential use as sustainable feed ingredients for improved hazelnut production and animal farming practices.

The growing demand for alternative clean energy sources and environmental crises are causing great concern for humankind. Researchers have devoted effort to finding cheap, eco-friendly, and robust functional materials for future development of the biorefinery process. Among biomass valorisation processes, gasification and pyrolysis are the most explored thermal treatments exploiting biomass-derived catalysts, especially for H2 and bio-oil production, which possess great potential in the energetical framework proposed by the European Green Deal. While biomass conversion provides intriguing insights, its industrial development has been limited to date. The economic and environmental sustainability of biomass-derived catalyst production is pivotal for reducing pollutant emissions. However, scientists face a bottleneck in synthesizing materials with a high surface area, strong functionalization, and cost-effectiveness to compete with fossil resources. To address this challenge, life cycle assessment emerges as a valuable tool to study process sustainability. This assessment can be coupled with artificial intelligence technologies to predict the properties of biomass-derived catalysts accurately, facilitating comprehensive sustainability analyses. Within a circular approach, cost-effective, tailored and robust biomass-derived catalysts to convert biomass play a key role in biorefinery developments.