Search Results (43)

The growing interest in sustainable food systems has spurred research into the valorisation of agro-industrial by-products as sources of bioactive compounds. This review provides a comprehensive overview of the phytochemical composition, bioactivity, biotransformation, and potential nutraceutical applications of by-products from chestnut (Castanea sativa Mill.) and grape (Vitis vinifera L.). Recent studies identify matrices such as chestnut leaves, shells, and burs, as well as grape pomace, skins, seeds, stems, and vine shoots, as rich in phenolic compounds, dietary fibres, vitamins, and minor bioactives, with antioxidant, anti-inflammatory, and antimicrobial properties. Emerging evidence highlights the importance of gastrointestinal digestion and microbial biotransformation in modulating the bioavailability and biological efficacy of phenolic compounds, particularly fibre-bound phenolics. The review further discusses state-of-the-art analytical approaches for chemical characterisation, including chromatographic and spectrophotometric methods, as well as emerging strategies for extraction, encapsulation, and delivery to enhance stability and bioavailability. Finally, the integration of chestnut and grapevine by-products into nutraceuticals, functional foods, and natural preservatives is critically examined from technological, safety, regulatory, and sustainability perspectives. Overall, this synthesis underscores the potential of these underutilised biomass streams as multifunctional raw materials that support waste valorisation, resource efficiency, and the development of next-generation health-promoting ingredients aligned with circular bioeconomy principles. Full article

Chestnut shells are widely recognized as a source of bioactive compounds, including polyphenols and other antioxidant molecules. The industrial chestnut food chain generates large amounts of this by-product, which represents both a waste disposal challenge and a potential source of promising biomolecules. Thermal treatments occurring during industrial processing, however, may affect both chemical composition and bioactivity. Characterization of the chemical composition and biological activity of chestnut shells can contribute to the valorisation of this industrial by-product. Understanding which molecular alterations are caused by the processing is essential to assess the real potential of chestnut shell biomass. This study provides a comparative analysis of Castanea sativa shells, both raw and industrially processed. Evaluation was performed at different levels, exploiting mass spectrometry–based metabolite profiling, Total Phenolic Index analysis, antioxidant capacity, and inhibitory activity against AKR1B and AKR1B10, two reductases involved in key physiopathologic pathways. A comparison between extraction solvents (water and ethanol) and processing status (raw versus industrially processed) was performed. Overall, our results support the view that chestnut shell residues represent a valuable source of bioactive extracts. In a circular economy framework, such extracts could be developed to act on AKR1B1/AKR1B10 activity and oxidative stress, thereby contributing to the valorisation of chestnut processing by-products. Full article

Global chestnut production has grown significantly in recent years, driven by its health benefits and growing interest in sustainable agriculture. Chestnut processing produces a solid residue consisting primarily of the fruit’s outer shell (pericarp), which is generally disposed of by on-farm combustion. However, this waste biomass shows a high potential for valorization due to its nutritional composition, particularly as a source of dietary fiber and polyphenols. In this study, the valorization potential of chestnut outer shells was evaluated through two approaches, demonstrating possible applicability at an industrial level: (1) the recovery of polyphenols using a simple and environmentally friendly extraction method, easily applicable on-farm, based on hot water as a solvent under different time–temperature combinations according to Response Surface Methodology (Central Composite Design); (2) the addition of chestnut outer shell flour during breadmaking as a source of fiber supplementation. Optimization of the extraction process using Response Surface Methodology combined with the desirability function identified optimal conditions at 102 min and 115 °C, yielding a maximum of approximately 172.30 mg of polyphenols per gram of dry outer shell. The incorporation of chestnut outer shell flour into bread formulations resulted in reduced dough workability, increased crust hardness (13.00 ± 0.87; 36.00 ± 1.00), and a darker bread color (1278.33 ± 39.27; 584.33 ± 25.90 RGB), particularly in the crumb. Full article

The European chestnut (Castanea sativa Mill.) industry generates substantial amounts of underutilized biomass, including shells, leaves, and spiny burs. Distinguishing itself from existing literature, this review presents a novel, integrated life-science analysis that redefines these by-products as a complementary ‘bioactive triad’, ranging from metabolic regulators to anti-virulence agents, rather than interchangeable sources of polyphenols. Although traditionally discarded, these by-products are rich sources of polyphenols, ellagitannins, and flavonoids, with promising potential for nutraceutical, cosmetic, and pharmaceutical applications. This review examines recent advances in the valorization of chestnut by-products, focusing on extraction strategies, chemical profiles, and biological activities. Shell valorization has increasingly shifted toward green extraction technologies, such as subcritical water extraction and deep eutectic solvents, which strongly influence bioactive recovery and composition. Chestnut leaves emerge as a sustainable resource enriched in hydrolysable tannins with anti-inflammatory and quorum sensing-inhibitory properties, particularly relevant for dermatological applications. Spiny burs, often the most phenolic-rich fraction, display marked antioxidant activity and the ability to potentiate conventional antibiotics against pathogens such as Helicobacter pylori. Despite these promising features, major challenges remain, including cultivar-dependent chemical variability, the predominance of in vitro evidence, and safety concerns related to the accumulation of potentially toxic elements. Overall, while chestnut by-products represent valuable resources within circular bioeconomy frameworks, their successful industrial and practical translation will require standardized extraction protocols, robust bioavailability assessments, and well-designed in vivo and clinical studies to ensure safety and efficacy. Full article

We explored the ability of the low molecular weight, polyphenol-rich fractions obtained from chestnut shells to inhibit ferroptosis in Friedreich Ataxia (FRDA), an inherited neuro- and cardio-degenerative disease. We prepared an aqueous extract by an eco-sustainable method and obtained a polyphenol-rich fraction (fraction D) of molecular weight less than 1.0 kDa after molecular size fractionation. The total phenols were 173.28 ± 4.97 μg gallic acid equivalents/mg fraction, and analysis by UHPLC-ITMSⁿ and RP-HPLC-UV revealed thirteen phenolic compounds with gallic acid and protocatechuic acid (PCA) as the most abundant (26.29 ± 2.19 and 4.93 ± 0.19 μg/mg fraction, respectively). Using a cellular assay based on patient-derived FRDA fibroblasts, we observed that chestnut shell dry extract at 20 µg/mL increased the survival of cells stressed with the ferroptosis inducer erastin from 8% to 45% and that this activity was dose-dependent. Fraction D at 20 µg/mL showed similar strong activity, increasing cell survival from 0.5% to 14% and decreasing lipid peroxidation by 42%. PCA, the most efficacious compound, doubled cell survival and decreased lipid peroxidation by 20%. Moreover, PCA increased the survival of cells in which frataxin was knocked down 1.5-fold and decreased ALOX12 expression. Our data suggest that PCA could be a promising molecule to explore FRDA pathophysiology. Full article

Chestnut (Castanea sativa Mill.) is a Mediterranean staple food valued for its cultural heritage, gastronomic identity, nutritional profile, bioactivities, and socio-economic and environmental relevance. This narrative review synthesizes current knowledge on chestnut fruits and by-products, linking ecophysiology and genetic diversity to chemical composition and functionality. It summarizes the nutrient profile (high starch and dietary fiber; gluten-free; B vitamins; essential minerals; and favorable fatty acids) and the diversity of phytochemicals—particularly phenolic acids, flavonoids, and ellagitannins (e.g., castalagin and vescalagin)—that underpin antioxidant, anti-inflammatory, antimicrobial, anti-proliferative, and metabolic effects demonstrated across in vitro, cellular, and in vivo models. We compare conventional and green extraction strategies (e.g., hydroethanolic, ultrasound-/microwave-assisted, and supercritical and subcritical water), highlighting method-dependent yields, composition, and bioactivity, and the valorization of shells, burs, and leaves within circular bioeconomy frameworks. Technological applications span functional foods (gluten-free flours, beverages, and emulsions), nutraceuticals, and cosmetics (skin-protective and regenerative formulations), and active packaging/biopolymers with antioxidant and antimicrobial performance. We discuss sources of variability (cultivar, environment, maturation, and processing) affecting bioactive content and efficacy, and outline future directions. Finally, this review emphasizes the importance of university-facilitated co-creation with companies and consumers—within the framework of Responsible Research and Innovation—as a pathway to strengthen the economic valorization and full utilization of the chestnut value chain, enhancing its societal relevance, sustainability, and health-promoting potential. Full article

Enzymatic browning (EB) is a physiological alteration that compromises the sensory and commercial quality of tree nuts, significantly reducing their market value and functional compound content. Due to its complexity and economic impact, this review compiles updated information on mechanisms and factors driving EB in tree nut species, as well as strategies for its prevention. The EB in tree nuts results from the oxidation of phenolic compounds (PCs) to brown pigments. This process is driven by enzymatic activity such as polyphenol oxidase (PPO), peroxidase (POD), and phenylalanine ammonium lyase (PAL) and strongly enhanced by cellular stress and associated regulation of gene expression. The EB has been documented in several tree nut species, including almonds, betel nuts, chestnuts, hazelnuts, macadamias, pecans, pistachios, and walnuts. This alteration developed both pre-harvest and post-harvest and was influenced by agronomic factors (such as cultivar, nutritional status, climatic conditions, and altitude) and handling (including shelling, storage, and processing). Mitigation strategies include the use of synthetic inhibitors, physical treatments, and the use of plant extracts rich in natural antioxidants, the latter perceived as more sustainable and safer alternatives. Full article

Every year, significant amounts of agro-industrial residues are generated. These residues contain several antioxidant compounds that can be extracted and applied to cosmetic products. In this study, phenolic-rich extracts from different agro-industrial residues (chestnut shell—CS, grape seed—GS, kiwi peel—KP, onion peel—OP, and pomegranate peel—PP) were obtained and their antioxidant potential and biocompatibility towards human fibroblasts (HFF-1) were evaluated. The total phenolic content ranged from 37.6 mg of gallic acid equivalents (GAE)/g for KP to 343.9 mg_GAE/g for CS. Moreover, CS, GS, OP, and PP extracts exhibited strong antioxidant properties, while KP showed more moderate potential. Biocompatibility tests demonstrated that CS and GS extracts were non-cytotoxic at concentrations below 500 mg/L, while OP and PP were safe up to 1000 mg/L. KP extracts were biocompatible up to 10,000 mg/L. This work demonstrated the bioactive potential of various agro-industrial residues for application in the cosmetic industry, given their antioxidant capacity. Additionally, it was the first to establish safe application limits for Soxhlet-extracted compounds, ensuring their safety to consumers. This research emphasises the importance of evaluating the biocompatibility of each extract before its incorporation into cosmetics, as their composition is highly variable. Full article

(1) Background: The use of cancer therapy is one of the most challenging arguments in cancer research and is in constant development. One of the principal problems connected with tumor therapy arises from the potential side effects connected with the classical chemotherapeutic treatment but also with molecular target therapy. The identification of novel molecules useful for the reduction of potential side effects but also as a new therapeutic opportunity is one of the hottest topics. (2) Methods: We identified castalin from chestnut shells by using NRM and LC-MS/MS. We treated different cancer cell lines with castalin alone or in combination with a CHK1 inhibitor. Finally, we performed an RNA-seq analysis of HeLa cells treated with castalin. (3) Results: We demonstrated the ability of castalin to induce DNA damage, probably by increasing ROS production. Consistently, antioxidant treatment, with ascorbic acid, reduced the DNA damage induced by castalin. Finally, we demonstrated the potential synergistic effect of castalin with SRA737, a CHK1 inhibitor currently used in clinical trials. (4) Conclusions: We demonstrated the ability of castalin to induce DNA damage favoring NHEJ repair. Moreover, the use of castalin in combination with SRA737 increased the efficacy of the CHK1 inhibitor, reducing its possible side effects. Full article

Chestnut (Castanea sativa Mill.) is an edible nut recognized for its nutritional attributes, particularly its elevated levels of carbohydrates (starch) and proteins. Chestnuts are popular for their health-promoting properties and hold significant environmental and economic importance in Europe. During this study, after the characterization of the fruit, attention was directed toward the valorization of chestnut shells, a predominant by-product of industrial chestnut processing that is typically discarded. Valuable bioactive compounds were extracted from the shells using Pressurized Liquid Extraction (PLE), a green, efficient, scalable method. Response surface methodology (RSM) was utilized to determine optimal extraction conditions, identified as 40% v/v ethanol as the solvent at a temperature of 160 °C for 25 min under a constant pressure of 1700 psi. High total polyphenol content (113.68 ± 7.84 mg GAE/g dry weight) and notable antioxidant activity—determined by FRAP (1320.28 ± 34.33 μmol AAE/g dw) and DPPH (708.65 ± 24.8 μmol AAE/g dw) assays—were recorded in the optimized extracts. Ultrahigh-performance liquid chromatography coupled with a hybrid trap ion mobility-quadrupole time-of-flight mass spectrometer (UHPLC-TIMS-QTOF-MS) was applied to further characterize the compound profile, enabling the identification of phenolic and antioxidant compounds. These findings highlight the possibility of using chestnut shell residues as a long-term resource to make valuable products for the food, medicine, cosmetics, and animal feed industries. This study contributes to the advancement of waste valorization strategies and circular bioeconomy approaches. Full article

Background/Objectives: Chestnut inner shells, traditionally used in Korean and Chinese herbal medicine, contain antioxidant and anti-inflammatory compounds that contribute to complementary medicine. This study aimed to explore the therapeutic effects of chestnut inner-shell extract (CIE) on skeletal muscle injury and atrophy using both in vivo and in vitro models. Methods: We used three experimental models representing distinct pathological mechanisms: (1) barium chloride (BaCl₂)-induced muscle injury to model acute myofiber damage, (2) sciatic nerve transection to model chronic neurogenic muscle atrophy, and (3) H₂O₂-treated C2C12 myoblasts to model oxidative-stress-related myogenic impairment. Histological analyses (e.g., hematoxylin and eosin staining and cross-sectional area measurement) and molecular analyses were performed to evaluate the effects of CIE on muscle structure, apoptosis, and oxidative stress. Results: In the BaCl₂ injury model, CIE treatment significantly restored the muscle fiber structure, with muscle protein levels returning to near-normal levels. In the denervation-induced muscle atrophy model, CIE treatment led to a dose-dependent decrease in apoptosis-related factors (especially cleaved caspase-3) and mitigated the Akt/mTOR signaling pathway. In the in vitro oxidative stress model, CIE suppressed the expression of NRF2 and HO-1, which are key oxidative stress response regulators. Conclusions: These findings suggest that CIE may offer therapeutic potential for mitigating skeletal muscle damage, atrophy, and oxidative stress. Full article

This study evaluated the use of brewer’s spent yeast (BSY) as an adsorbent for tannins from a chestnut shell extract (CS tannin extract). This extract was derived from an alkaline treatment (5% NaOH (v/v)) to recover cellulosic material from chestnut shells and needed valorization. Various BSY treatments, including lyophilization, immobilization in calcium alginate beads, and alkaline and acid treatments, were tested to identify which had the best tannin adsorption capacity. The results highlight BSY’s potential as a system to valorize tannins from this treatment solution. Full article

The irradiation by gamma-rays is a widely used technique for disinfection in the pharmaceutical and cosmetic industries. In view of growing concerns by consumers about this technique, further investigation of the effects of radiation is required. In this work electron paramagnetic resonance (EPR) spectroscopy was applied to study the free radicals in irradiated horse chestnut (Aesculus hippocastanum L.) seeds and to evaluate the free radical scavenging activity (FRSA) using the stable DPPH radical. In order to evaluate the antiradical potential, a spectrophotometric study was also used. The identification and quantification of some individual polyphenol compounds before and after irradiation by 1, 5, and 10 kGy gamma rays of peeled and shell seeds were obtained by high performance liquid chromatography (HPLC). The EPR spectrum recorded on irradiated horse chestnut is a typical signal for irradiated cellulose-contained substances. The results show that the signal is stable, and it can be found in the samples irradiated with a dose of 1 kGy, 45 days after treatment, whereas for samples irradiated by 5 and 10 kGy, it is even found 250 days later. The study showed that free radical scavenging activity increases in shell seeds, while it decreases in peeled seed extracts after irradiation depending on the dosage, which corresponds to the total phenolic content. Shell seed extracts have significantly stronger antiradical activity than that of peeled seeds. Regarding the HPLC analysis, some polyphenolics were degraded and others were formed as a result of irradiation. The irradiation by 5 kGy dosage has a most significant positive effect on the antioxidant potential of shell chestnut seeds. Full article

Recently there has been growing interest in dyeing biomaterials using natural sustainable plant extracts classified as eco-friendly. The microwave-assisted method provides fast heating and energy efficiency, more homogenous heat distribution in dyeing baths, less use of chemicals, and less heat loss, resulting in this method being greener—more sustainable and ecological. Artificial neural networks (ANNs) are used to predict the dyeing properties of fibers, which are often complex and dependent on multiple variables. This saves time and reduces costs compared to trial-and-error methods. This study presents the green dyeing of merino wool fiber with natural dye extracted from Aesculus hippocastanum (horse chestnut) shells using the microwave-assisted method. Before dyeing, the merino wool fiber underwent a pre-mordanted process with aluminum potassium sulfate with different concentrations using the microwave-assisted method. Spectrophotometric analysis of the light, washing, and rubbing fastness of the dyed merino wool fibers was performed. The color strength, light, washing, and rubbing fastness of the dyed merino wool fiber were developed using the pre-mordanting process. After the pre-mordanting process, the light fastness of the samples improved from 1–2 to 3, the color change increased from 2 to 3–4, and the rubbing fastness developed from 2–3 to 4 according to mordant concentration, mordanting time, and dyeing time quantities. The spectrophotometric analysis results indicate that color coordinates vary based on mordant concentration, mordanting, and dyeing duration. Furthermore, the results proved that microwave energy significantly shortened the mordanting and dyeing duration, resulting in an eco-friendly dyeing process. In this investigation, a feed-forward neural network (FFNN) model with sigmoid hidden neurons and a linear output neuron was used to predict the color strength dyeing property of merino wool fiber. Experimental results showed that the proposed model achieved a regression value of 0.9 for the color strength dyeing property. As demonstrated, the proposed FFNN model is effective and can be utilized to forecast the color strength dyeing properties of merino wool fiber. Full article

Castanea sativa Mill. (C. sativa) processing and pruning generate several by-products, including leaves, burs, and shells (inner and outer teguments), which are considered an important source of high-value phytochemicals. Ellagitannins from C. sativa leaf extracts have been described to impair H. pylori viability and inflammation in gastric cells. Furthermore, chestnut shells showed an important anti-inflammatory effect in gastric epithelial cells. Dietary polyphenols, including tannins, have been reported to interfere with targets of inflammation, including the nuclear factor κB (NF-κB). A promising role as a further therapeutical target for gut disorders has been recently proposed for the regulatory subunit of hypoxia-inducible factor (HIF-1α), as a potential stabilizer of intestinal barrier integrity. Therefore, the main objective of this work is the chemical characterization of several chestnut by-products (bud, spiny bur, wood, pericarp and episperm), together with the exploitation of their anti-inflammatory properties in intestinal cells, scavenging capacity, and stability following gastrointestinal digestion. The chemical characterization confirmed the presence of bioactive polyphenols in the extracts, including ellagitannins. In CaCo-2 cells stimulated by an IL-1β-IFN-γ cocktail, nearly all chestnut by-products (50 µg/mL) inhibited the release of proinflammatory mediators (CXCL-10, IL-8, MCP-1, ICAM), along with the NF-κB-driven transcription, and induced the HRE-driven transcription. The stability of the most promising extracts, identified through PCA and cluster analysis, was addressed by in vitro gastrointestinal digestion. Despite the significant reduction in total polyphenol index of chestnut bud and wood after gastric and intestinal digestion, the activity of these extracts on both scavenging and anti-inflammatory parameters remained promising. These data contribute to exploit the potential of chestnut by-products as sources of dietary polyphenols with anti-inflammatory properties at the intestinal level. Moreover, this study could represent an important step to encourage the recycling and valorization of chestnut by-products, promoting the circular economy and reducing the environmental impact related to the management of agriculture waste. Full article