Submit to Special Issue Submit Abstract to Special Issue Review for Antioxidants Propose a Special Issue

Journal Menu

Journal Browser

Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition

Special Issue Editors
Special Issue Information
Keywords
Benefits of Publishing in a Special Issue
Published Papers

A special issue of Antioxidants (ISSN 2076-3921). This special issue belongs to the section "Extraction and Industrial Applications of Antioxidants".

Deadline for manuscript submissions: 10 July 2026 | Viewed by 18652

Share This Special Issue

Special Issue Editors

Prof. Dr. Silvana Hrelia

E-Mail Website
Guest Editor

Department for Life Quality Studies, Alma Mater Studiorum, University of Bologna, 47921 Rimini, Italy
Interests: cellular biochemistry; nutritional biochemistry; oxidative stress; antioxidants; nutraceuticals
Special Issues, Collections and Topics in MDPI journals

Prof. Dr. Cristina Angeloni

E-Mail Website
Guest Editor

Department for Life Quality Studies, Alma Mater Studiorum, University of Bologna, Bologna, Italy
Interests: nutritional biochemistry; neurodegenerative diseases; oxidative stress; inflammation; nutraceuticals; ageing
Special Issues, Collections and Topics in MDPI journals

Dr. Maria Cristina Barbalace

E-Mail Website
Guest Editor

Department for Life Quality Studies, Alma Mater Studiorum, University of Bologna, Bologna, Italy
Interests: cellular biochemistry; nutraceuticals; neurodegeneration; oxidative stress; inflammation; antioxidants
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

One of the main factors contributing to food unsustainability is the significant waste and loss generated at every stage of the food supply chain. This leads to resource depletion and exacerbates environmental degradation. According to the Food and Agriculture Organization (FAO), approximately one-third of all food produced globally, equivalent to about 1.3 billion tons annually, is lost or wasted, causing enormous environmental consequences. In this context, emerging solutions, including agri-food waste upcycling, are in high demand. These approaches convert by-products and waste materials into high-value molecules, reducing the environmental impact while promoting innovation and economic growth.

In recent years, the scientific community has focused on developing sustainable solutions to transform food waste into valuable products due to the chemical composition that makes it a natural reservoir of bioactive compounds with potential health benefits for humans.

Agri-food waste includes a wide range of discarded parts from crops, fruits, and vegetables generated at different stages of the agricultural food supply chain, such as farming, harvesting, storage, and processing. Due to their perishable nature and short shelf life, fruits and vegetables pose challenges in the agri-food supply chain, resulting in substantial losses. These wastes include, but are not limited to, fruit skins, vegetable peels, seeds, stems, and other inedible or underutilized parts.

Agricultural by-products are increasingly being viewed as reservoirs of bioactive compounds with beneficial properties for human health. Phytochemicals are naturally occurring compounds found in plants that contribute to their color, flavor, and pest resistance. These bioactive substances, including flavonoids, alkaloids, and terpenes, are not classified as essential nutrients, but are widely recognized for their health benefits, encompassing antioxidant, anti-inflammatory, and antimicrobial properties. They have been extensively studied for their potential applications in pharmaceuticals, cosmetics, and functional foods, offering natural alternatives to synthetic compounds.

Key goals in this field of research include identifying bioactive molecules found in agri-food by-products, designing environmentally sustainable extraction methods, and evaluating the biological properties of these compounds for potential health-related applications, including in the cosmeceutical sector.

In this fourth Special Issue on “Agri-Food Wastes as Natural Source of Bioactive Antioxidants”, our objective is to further explore the multifaceted dimensions of this topic. In particular, we will consider research and review papers on economically viable and ecologically responsible extraction methods and on the use of agri-food wastes to produce antioxidant bioactive compounds, as well as papers on “in vitro” and “in vivo” studies of the effects of these compounds/extracts, emphasizing the capacity of agri-food waste bioactive molecules to modulate the intricate signaling networks underpinning the development and progression of chronic and degenerative diseases, and protecting human health. Integrating sustainable practices into product formulation addresses environmental concerns and presents significant economic opportunities in the health product/cosmeceutical sector.

Prof. Dr. Silvana Hrelia
Dr. Cristina Angeloni
Dr. Maria Cristina Barbalace
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 250 words) can be sent to the Editorial Office for assessment.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Antioxidants is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2900 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

agri-food by-products
agri-food waste
nutraceuticals
functional foods
cosmeceutical products
sustainable practices
bioactive compounds
health effects

Benefits of Publishing in a Special Issue

Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
Reprint: MDPI Books provides the opportunity to republish successful Special Issues in book format, both online and in print.

Further information on MDPI's Special Issue policies can be found here.

Published Papers (10 papers)

Download All Papers

Order results

Result details

Show export options Show export options

Select all

Export citation of selected articles as:

Research

Jump to: Review

18 pages, 854 KB

Open AccessArticle

Exploiting Solanum tuberosum L. (Vitelotte Noire Cultivar) Peel as a Sustainable Antioxidant Source for Nutraceutical Applications

by Stefania Peddio, Sonia Lorrai, Alessandra Padiglia, Pierluigi Caboni, Cristina Manis, Antonio Rescigno and Paolo Zucca

Antioxidants 2026, 15(5), 568; https://doi.org/10.3390/antiox15050568 - 30 Apr 2026

Viewed by 334

Abstract

The valorization of agri-food by-products aligns with circular economy principles and offers sustainable sources of bioactive compounds. This study investigated the peels of the purple-fleshed Solanum tuberosum L. cv. Vitelotte Noire (VN), cultivated in Sardinia, as a potential resource for nutraceutical antioxidants. Extracts were obtained using solvents of different polarities (water, 80% and 96% ethanol) and characterized. Phytochemical screening revealed high concentrations of total phenolics, flavonoids, and anthocyanins, with the 96% ethanolic extract showing superior anthocyanin content. Antioxidant capacity, assessed via ORAC-PYR, TEAC-ABTS, and DPPH assays, was highest in the alcoholic extracts. Furthermore, all extracts showed protective effects in an in vitro model of AAPH-induced oxidative DNA damage, as indicated by the preservation of plasmid supercoiling. Untargeted LC-QTOF-MS analysis detailed a rich metabolomic profile, including organic acids, amino acids, and vitamins. The findings confirm VN peel as a potent, sustainable source of antioxidants, supporting its valorization for developing high-added-value nutraceutical and functional food ingredients, while reducing waste disposal costs and environmental impact. Full article

(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition)

► Show Figures

Figure 1

22 pages, 1176 KB

Open AccessArticle

Optimization of Phenolic Compounds Recovery from Pistachio Hull Using Accelerated Solvent Extraction

by Ana I. Paniagua-García, Lucía Gómez-González, Silvia González-Rojo and Rebeca Díez-Antolínez

Antioxidants 2026, 15(5), 558; https://doi.org/10.3390/antiox15050558 - 28 Apr 2026

Viewed by 256

Abstract

Pistachio hull (PH) is the largest by-product of the pistachio industry. It contains high levels of phenolic compounds, which have antioxidant properties and promote health. However, PH can accumulate during harvesting, potentially resulting in environmental pollution. This study aimed to optimize the operational conditions for conventional solvent extraction (CSE) and accelerated solvent extraction (ASE) of phenolic compounds from PH using response surface methodology (RSM). The extracts obtained under optimal conditions for the two extraction techniques were compared. The highest values of phenolic recovery (9.92 ± 0.09 g gallic acid equivalent (GAE)/100 g dried matter (DM)) and radical-scavenging activity for α,α-diphenyl-β-picrylhydrazyl (DPPH) (IC50 = 0.16 ± 0.00 mg/mL) were achieved by the extract obtained by ASE (23% ethanol in water, 180 °C, 15 min). Regarding individual phenolic compounds, gallic acid accounted for 35.7–48.1% of the total phenolic compounds contained in the PH extracts, followed by 3,4-dihydroxybenzoic acid, 4-hydroxybenzoic and 2,5-dihydroxybenzoic acid. The findings of this study demonstrate for the first time that PH can be valorized by ASE using eco-friendly solvents, obtaining extracts with a high phenolic content, reducing waste and promoting the bioeconomy development. Full article

(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition)

► Show Figures

Figure 1

26 pages, 1636 KB

Open AccessArticle

Apple Pomace as a Source of Valuable Phenolics: From Drying Kinetics to Optimization of Ultrasound-Assisted Extraction Using Conventional and Alternative Solvents

by Silviu Măntăilă, Nicoleta Balan, Ștefania Adelina Milea, Oana Viorela Nistor, Doina Georgeta Andronoiu, Gabriel Dănuț Mocanu, Gabriela Râpeanu and Nicoleta Stănciuc

Antioxidants 2026, 15(4), 429; https://doi.org/10.3390/antiox15040429 - 29 Mar 2026

Viewed by 631

Abstract

Industrial processing of apple to obtain products like juice or cider generates a significant amount of pomace, which represents 25–30% of the fresh fruit mass. Different technologies are needed to valorize apple pomace (AP), considering its significant amount of high-value compounds, such as fiber, vitamins, and polyphenols. Hot-air convection (CA) and infrared (IR) drying are widely used methods for preserving polyphenols from by-products, such as apple pomace (AP), while also extending their shelf life. This study aimed to evaluate the influence of CA and IR drying on drying kinetics, color parameters, and the preservation of polyphenolic compounds, as well as to identify a sustainable extraction approach. Both drying methods significantly affected the color characteristics and content of polyphenols with high antioxidant activity. A significant impact was noticed at higher temperatures, which may be associated with the partial inactivation of browning enzymes. IR drying resulted in a shorter drying time and lower specific energy consumption compared to CA. Furthermore, the assessment of solvent efficiency in ultrasound-assisted extraction (UAE) indicated that the natural deep eutectic solvent (NaDES) composed of choline chloride and glycerol (1:1 molar ratio) provided superior recovery of phenolic compounds with high antioxidant activity compared to conventional solvents and the other NaDES analyzed. Optimization of UAE conditions using this polyol-based NaDES allowed for achieving an extract characterized by a polyphenolic profile dominated by flavan-3-ols (catechin and epigallocatechin), followed by phenolic acids, mainly chlorogenic acid. These results confirm the potential of AP as a valuable source of bioactive compounds and of polyol-based NaDESs as a sustainable and efficient alternative for their recovery. Full article

(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition)

► Show Figures

Figure 1

19 pages, 1627 KB

Open AccessArticle

Accelerated Solvent Extraction as an Alternative for the Recovery of Phenolic Compounds from Chestnut Bur: Optimization of Extraction Conditions

by Ana I. Paniagua-García, Lucía Gómez-González, Silvia González-Rojo and Rebeca Díez-Antolínez

Antioxidants 2026, 15(2), 207; https://doi.org/10.3390/antiox15020207 - 4 Feb 2026

Cited by 1 | Viewed by 735

Abstract

Chestnut bur (CB) is a solid waste product generated in large quantities during the harvesting of edible fruits. This by-product is rich in total phenolic content (TPC) with high antioxidant properties, making it suitable for use in a variety of industrial applications. In this study, the operational variables of accelerated solvent extraction (ASE) and conventional solvent extraction (CSE) of CB were optimized in order to obtain extracts with maximum levels of TPC. The analysis revealed that the extract obtained by ASE using 31.3% ethanol at 180 °C for 9 min achieved the highest value of TPC (8.37 ± 0.05 g gallic acid equivalents (GAE)/100 g dry matter (DM)). Moreover, this extract exhibited higher values of radical-scavenging activity for α,α-diphenyl-β-picrylhydrazyl (DPPH) (90.8 ± 0.3%) than those observed for catechin standard (88.7 ± 0.2%). In addition, its phenolic composition revealed high amounts of gallic acid (13.22 ± 1.01 mg/g DM), followed by 3,4-dihydroxybenzoic acid (2.96 ± 0.16 mg/g DM). This study demonstrates the potential for valorization of CB by ASE under feasible extraction conditions, thereby promoting the circular economy. Full article

(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition)

► Show Figures

Figure 1

25 pages, 9226 KB

Open AccessArticle

Insights into Bioactive Constituents from Pericarp of Garcinia mangostana: Anti-Inflammatory Effects via NF-κB/MAPK Modulation and M1/M2 Macrophage Polarization

by Cheng-Shin Yang, Sin-Min Li and Jih-Jung Chen

Antioxidants 2026, 15(1), 128; https://doi.org/10.3390/antiox15010128 - 19 Jan 2026

Cited by 1 | Viewed by 908

Abstract

Mangosteen (Garcinia mangostana L.) has long been used in traditional Southeast Asian medicine to treat inflammatory-related conditions. In this study, three new compounds, including garcimangone A (1), garcimangone B (2), and the S-form of garcimangone C (3), and 18 known compounds were isolated and investigated for their anti-inflammatory properties and effects on M1- and M2-associated markers. Among the isolated components, γ-mangostin (5), garcinone D (6), morusignin J (15), and fuscaxanthone C (16) showed the most potent NO-inhibitory effects in LPS-stimulated RAW264.7 cells. SAR study revealed that chromeno moiety at C-3,4, oxygen substituents at C-1,3,6,7, and isoprenyl groups at C-2,8 are key structural features that promoted anti-inflammatory activity. Cytokine analysis results indicated that morusignin J (15) and fuscaxanthone C (16) could modulate the production of pro-inflammatory cytokines, such as TNF-α and IL-6, while modulating the anti-inflammatory cytokine IL-10. Western blot results demonstrated that morusignin J (15) modulated the inflammatory response through NF-κB and MAPK signaling and increased the expression of M2-associated markers KLF4 and arginase-1 in LPS-induced RAW264.7 macrophages. Further molecular docking analysis confirmed the high binding affinity of morusignin J (15) with key iNOS residues, such as Gln257, Pro344, Glu371, and Hem901, and the in silico prediction supported its potent oral bioavailability and drug-likeness. These in vitro and in silico findings highlight that pericarps of G. mangostana possess potential as promising natural sources for functional extracts and bioactive constituents for the development of antioxidative and anti-inflammatory candidates, and warrant further in vivo investigation in the future. Full article

(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition)

► Show Figures

Figure 1

34 pages, 1551 KB

Open AccessArticle

Brine Enriched with Olive Wastewater Phenols: A Green Strategy to Reduce Nitrites in Cooked Ham

by Dario Mercatante, Stefania Balzan, Sonia Esposto, Sara Barbieri, Federico Fontana, Luca Fasolato, Vincenzo De Rosa, Maurizio Servili, Agnese Taticchi, Enrico Novelli and Maria Teresa Rodriguez-Estrada

Antioxidants 2025, 14(9), 1124; https://doi.org/10.3390/antiox14091124 - 17 Sep 2025

Viewed by 1291

Abstract

This study aimed to evaluate the effects of brine enriched with an olive vegetation water (OVW) extract on the physico-chemical, oxidative, and sensory characteristics of cooked ham during storage, as a strategy to partially or totally replace nitrites. Four brines formulated with different concentrations of nitrites in combination with 200 mg of OVW extract/kg product were tested; the cooked ham samples were sliced, placed in trays, packed in a protective atmosphere, and monitored for 30 days at 4 °C. The results showed that phenolic compounds derived from OVW effectively reduced lipid and protein oxidation, limiting the formation of secondary oxidation products such as thiobarbituric acid reactive substances, volatile aldehydes, and cholesterol oxides. Sensory analysis confirmed that the extract did not negatively affect the organoleptic properties of the ham, while also helping to preserve color stability. These findings suggest that brine enriched with OVW phenols can be a promising green strategy to reduce nitrites in cooked ham, which also promotes the sustainable valorization of olive oil by-products. Full article

(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition)

► Show Figures

Figure 1

17 pages, 6462 KB

Open AccessArticle

Dragon Fruit Peel (Hylocereus undatus) Modulates Hepatic Lipid Metabolism and Inflammation in a Rat Model of High-Fat, High-Fructose-Induced Metabolic Dysfunction

by Siriwan Chumroenvidhayakul, Thavaree Thilavech, Mahinda Yapa Abeywardena, Michael Conlon, Julie Dallimore, Michael Adams, Beverly Muhlhausler and Sirichai Adisakwattana

Antioxidants 2025, 14(3), 319; https://doi.org/10.3390/antiox14030319 - 6 Mar 2025

Cited by 2 | Viewed by 6242

Abstract

Metabolic dysfunction and hepatic abnormalities, such as those associated with high-fat, high-fructose (HFHFr) diets, are major contributors to obesity-related health issues. The growing interest in sustainable dietary interventions has highlighted the potential of plant-based byproducts. Dragon fruit (Hylocereus undatus) peel waste, rich in bioactive compounds such as dietary fibers, phenolics, and betacyanins, represents a promising functional ingredient for managing these disorders. This study investigated the effects of dragon fruit peel powder (DFP) on metabolic dysfunction and hepatic abnormalities induced by a HFHFr diet in rats. Over 12 weeks, the rats were fed a standard AIN-93M diet (control or C), C with 5% (w/w) DFP (C + DFP), a HFHFr diet, or a HFHFr diet with 5% (w/w) DFP (HFHFr + DFP). DFP supplementation significantly reduced HFHFr-induced body weight gain, visceral adiposity, insulin resistance, and dyslipidemia while also lowering systolic blood pressure and systemic oxidative stress markers. In the liver, DFP supplementation attenuated fat accumulation and lipid peroxidation, reduced glycogen storage abnormalities, and modulated the expression of lipid metabolism and inflammatory genes. These findings suggest that DFP may serve as a functional dietary supplement for preventing and managing metabolic disorders and liver abnormalities associated with excessive fat and fructose consumption. Full article

(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition)

► Show Figures

Figure 1

18 pages, 909 KB

Open AccessArticle

Phenolic Composition and Antioxidant Activity of Edible Flowers: Insights from Synergistic Effects and Multivariate Analysis

by Cristiana Breda, Amanda Nascimento, Parkash Meghwar, Hugo Lisboa, Alfredo Aires, Eduardo Rosa, Luís Ferreira and Ana Novo Barros

Antioxidants 2025, 14(3), 282; https://doi.org/10.3390/antiox14030282 - 27 Feb 2025

Cited by 17 | Viewed by 3143

Abstract

The phenolic composition and antioxidant activity of four edible flowers—Orange marigold, yellow marigold, rose geranium, and Rosa de Santa Teresinha—were evaluated to explore their potential as natural antioxidants. Rosa de Santa Teresinha exhibited the highest total phenol content (83.34 ± 2.09 mg GA g⁻¹ DW) and ortho-diphenol content (168.91 ± 0.15 mg GA g⁻¹ DW), while the marigolds showed significantly lower levels (~17 mg GA g⁻¹ DW for total phenols). Antioxidant activity, determined via ABTS, DPPH, and FRAP assays, ranged from 0.11 to 0.96 mmol Trolox g⁻¹ DW, with rose geranium and Rosa de Santa Teresinha achieving the highest values. Theoretical antioxidant contributions, calculated based on the identified phenolic compounds, accounted for only a small fraction of the measured activity, with observed values exceeding predictions by factors of 56 to 1416, indicating the presence of synergistic interactions and additional bioactive compounds. Multivariate analyses (PCA and PLS regression) identified luteolin-7-O-glucoside and quercetin-3-O-galactoside as primary contributors to antioxidant capacity. These results underscore the importance of synergistic effects in edible flowers and highlight their potential as functional ingredients for nutraceutical applications. Full article

(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition)

► Show Figures

Figure 1

29 pages, 6143 KB

Open AccessArticle

Sustainable Utilization of Coffee Pulp, a By-Product of Coffee Production: Effects on Metabolic Syndrome in Fructose-Fed Rats

by Nelson Andrade, Ilda Rodrigues, Francisca Carmo, Gabriela Campanher, Isabella Bracchi, Joanne Lopes, Emília Patrício, João T. Guimarães, Juliana A. Barreto-Peixoto, Anabela S. G. Costa, Liliana Espírito Santo, Marlene Machado, Thiago F. Soares, Susana Machado, Maria Beatriz P. P. Oliveira, Rita C. Alves, Fátima Martel and Cláudia Silva

Antioxidants 2025, 14(3), 266; https://doi.org/10.3390/antiox14030266 - 25 Feb 2025

Cited by 4 | Viewed by 2463

Abstract

Metabolic syndrome (MetS) is a cluster of metabolic abnormalities that include insulin resistance, impaired glucose tolerance, dyslipidemia, hypertension, and abdominal obesity. Coffee production generates large quantities of waste products, which pose a serious threat to the environment. However, coffee by-products, such as coffee pulp (CP), possess an undeniable wealth of bioactive components. Based on this, we investigated whether a 10-week dietary intervention with 250 mg/kg/d of CP could prevent or ameliorate MetS in high-fructose-fed rats. Consumption of CP by rats fed a high-fructose diet reduced body weight gain, lowered systolic blood pressure (SBP), fasting plasma glucose and insulin levels, and improved insulin resistance compared to rats fed a high-fructose diet alone. At the hepatic level, CP attenuated the increase in lipid storage, reduced lipid peroxidation, and improved glutathione levels when combined with a high-fructose diet. CP also affected the expression of key genes related to glucose and lipid metabolism in hepatic and adipose tissues, in rats fed a fructose-rich diet. This study demonstrates that CP ameliorates several consequences of high-fructose-induced MetS in the rat (weight gain, hypertension, glucose intolerance, insulin resistance, changes in liver, and adipose tissue function). Hence, our data provide evidence that CP consumption in the context of a high-fructose diet can be used to improve MetS management. Full article

(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition)

► Show Figures

Figure 1

Review

Jump to: Research

16 pages, 591 KB

Open AccessReview

Antioxidant and Health-Related Effects of Tannins: From Agri-Food By-Products to Human and Animal Health

by Luca Camarda, Roberta Budriesi, Ivan Corazza, Maria Frosini, Carla Marzetti and Laura Beatrice Mattioli

Antioxidants 2026, 15(1), 104; https://doi.org/10.3390/antiox15010104 - 13 Jan 2026

Cited by 3 | Viewed by 1562

Abstract

Background: Agri-food by-products are increasingly recognized as valuable sources of tannins, whose antioxidant properties represent the primary driver of their biological activity across human and animal health. The strong redox-modulating capacity of condensed and hydrolysable tannins provides a unifying mechanistic explanation for their effects on inflammation, metabolism, gut integrity and neuroprotection. Methods: This narrative review synthesizes evidence obtained through a structured literature search across major databases, selecting studies that investigated antioxidant mechanisms of tannin-rich matrices from plant- and processing-derived residues. Results: Condensed tannins, particularly proanthocyanidins, consistently display potent antioxidant activity through radical scavenging, metal chelation and activation of endogenous defenses, thereby underpinning their anti-inflammatory, anti-ischemic, neuroprotective and metabolic actions. Hydrolysable tannins similarly exert strong antioxidative effects that support antimicrobial activity, enzyme modulation and protection against neuroinflammation. In animals, the antioxidant capacity of tannins translates into improved oxidative balance, enhanced immune status, reduced tissue damage, better feed efficiency and mitigation of oxidative stress-linked methane emission pathways. Conclusions: Antioxidant activity emerges as the central, cross-species mechanism through which tannins mediate diverse health benefits. Tannin-rich agri-food by-products therefore represent promising sustainable antioxidant resources, although their efficacy remains influenced by tannin class, degree of polymerization and dosage, warranting further mechanistic and translational research. Full article

(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition)

► Show Figures

Journal Menu

Journal Browser

Agri-Food Wastes as Natural Source of Bioactive Antioxidants: Fourth Edition

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Published Papers (10 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI