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19 pages, 2275 KiB

Open AccessArticle

Sustainable Valorization of Coffee Silverskin Waste: Pressurized Liquid Extraction of Bioactive Compounds

by Sokratis E. Koskinakis, Chrysanthos Stergiopoulos, Christoforos Vasileiou and Magdalini Krokida

Foods 2025, 14(4), 615; https://doi.org/10.3390/foods14040615 - 12 Feb 2025

Viewed by 1144

Abstract

Coffee silverskin, a by-product of the coffee roasting industry, offers significant potential for valorization due to its bioactive compound content. This study optimized the Pressurized Liquid Extraction (PLE) process for recovering phenolic compounds and caffeine from coffee silverskin. A factorial design identified the [...] Read more.

Coffee silverskin, a by-product of the coffee roasting industry, offers significant potential for valorization due to its bioactive compound content. This study optimized the Pressurized Liquid Extraction (PLE) process for recovering phenolic compounds and caffeine from coffee silverskin. A factorial design identified the temperature and ethanol concentration as the key parameters influencing extraction yield, antioxidant capacity (TEAC), total phenolic content (TPC) and caffeine and phenolic acid contents. These factors were further optimized using a central composite design (CCD) and Response Surface Methodology (RSM). The optimal extraction conditions—140 °C and 55% ethanol—achieved a balanced enhancement across all responses: 12.1% extraction yield, 65.3 mg TE/g dry extract for antioxidant capacity, 88.4 mg GAE/g dry extract for total phenolic content, 56.7 mg caffeine/g dry extract, and 10.6 mg chlorogenic acid equivalents/g dry extract for phenolic acid content. Compared to conventional methods, the optimized PLE demonstrated superior bioactive compound recovery while employing environmentally friendly solvents. This approach underscores PLE’s potential as a sustainable technology for valorizing agro-industrial by-products, contributing to both waste reduction and the development of antioxidant-rich products. Full article

(This article belongs to the Special Issue The Extraction, Characterization and Application of Functional Ingredients from Agri-Food Wastes and By-Products)

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20 pages, 4584 KiB

Open AccessArticle

Almond Hull Extract Valorization: From Waste to Food Recovery to Counteract Staphylococcus aureus and Escherichia coli in Formation and Mature Biofilm

by Sara D’Arcangelo, Debora Santonocito, Luciano Messina, Valentina Greco, Alessandro Giuffrida, Carmelo Puglia, Mara Di Giulio, Rosanna Inturri and Susanna Vaccaro

Foods 2024, 13(23), 3834; https://doi.org/10.3390/foods13233834 - 28 Nov 2024

Cited by 3 | Viewed by 1271

Abstract

The increase in food waste accumulation needs innovative valorization strategies that not only reduce environmental impacts but also provide functional applications. This study investigates the potential of almond hulls, an abundant agricultural by-product, as a source of bioactive compounds. For the first time, [...] Read more.

The increase in food waste accumulation needs innovative valorization strategies that not only reduce environmental impacts but also provide functional applications. This study investigates the potential of almond hulls, an abundant agricultural by-product, as a source of bioactive compounds. For the first time, almond hull extract (AHE), was evaluated in terms of anti-adhesive and anti-biofilm activity against Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 9637. The extract was obtained by an optimized eco-friendly green technique using ultrasound-assisted extraction (UAE), and it was characterized for its main compounds by high-performance liquid chromatography–mass spectrometry (HPLC-MS) and nuclear magnetic resonance (NMR) analysis. Antimicrobial activity was evaluated on planktonic cells by minimum inhibitory/bactericidal concentration (MIC/MBC) and by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays. Afterward, AHE activity was evaluated against the bacterial sessile phase, both against in-formation and mature biofilm. Finally, the toxicity of the extract was tested on normal human adult cells (HDFa) by an MTT test. The principal active compounds present in AHE belong to the polyphenol group, in particular, the phenolic acid (Hydroxycinnammic sub-class) and, more significantly, the flavonoid class. The results showed that the extract has a relevant antimicrobial activity against the planktonic cells of both tested strains. Moreover, it significantly inhibited bacterial adhesion and promoted biofilm removal, highlighting its potential as a sustainable antimicrobial agent. The MTT test on human fibroblasts showed that the extract is not toxic for normal human cells. This research highlights how food waste valorization could have a high potential in the antimicrobial field. Full article

(This article belongs to the Special Issue The Extraction, Characterization and Application of Functional Ingredients from Agri-Food Wastes and By-Products)

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13 pages, 2205 KiB

Open AccessArticle

Drying of Saffron Petals as a Critical Step for the Stabilization of This Floral Residue Prior to Extraction of Bioactive Compounds

by Inmaculada Criado-Navarro, Francisco Barba-Palomeque, Pedro Pérez-Juan, Carlos A. Ledesma-Escobar and Feliciano Priego-Capote

Foods 2024, 13(23), 3724; https://doi.org/10.3390/foods13233724 - 21 Nov 2024

Viewed by 1027

Abstract

Saffron petals represent floral biomass generally wasted due to rapid deterioration. Previous characterization studies have revealed the presence of bioactive compounds in petals, such as flavonols and anthocyanins. Petal stabilization is a challenge for the efficient isolation of these compounds. This research evaluated [...] Read more.

Saffron petals represent floral biomass generally wasted due to rapid deterioration. Previous characterization studies have revealed the presence of bioactive compounds in petals, such as flavonols and anthocyanins. Petal stabilization is a challenge for the efficient isolation of these compounds. This research evaluated three different drying techniques before the solid–liquid extraction of bioactive compounds: oven-drying (40 and 60 °C), lyophilization, and vacuum evaporation (25 and 50 °C). The characterization of the extracts allowed the annotation of 22 metabolites with a quantitative predominance of anthocyanins and derivatives of kaempferol and quercetin. Oven-drying at 60 °C was the most suitable approach for extracting minor compounds, such as crocins and safranal, at concentrations below 1 mg/g dry weight. Vacuum evaporation (50 °C) and lyophilization were the most recommended strategies for efficiently isolating flavonoids. Therefore, drying saffron petals is crucial to ensure the efficient extraction of bioactive compounds. Full article

(This article belongs to the Special Issue The Extraction, Characterization and Application of Functional Ingredients from Agri-Food Wastes and By-Products)

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15 pages, 2561 KiB

Open AccessArticle

Effect of Pulsed Electric Field Pretreatment on the Concentration of Lipophilic and Hydrophilic Compounds in Cold-Pressed Grape Seed Oil Produced from Wine Waste

by Natka Ćurko, Katarina Perić, Tomislava Vukušić Pavičić, Sandra Balbino, Marina Tomašević, Damir Iveković, Ivana Radojčić Redovniković and Karin Kovačević Ganić

Foods 2024, 13(14), 2299; https://doi.org/10.3390/foods13142299 - 22 Jul 2024

Viewed by 1293

Abstract

Pretreatment of grape pomace seeds with a pulsed electric field (PEF) was applied to improve the extraction yield of cold-pressed grape seed oil. The effects of different PEF conditions, electric field intensities (12.5, 14.0 and 15.6 kV/cm), and durations (15 and 30 min) [...] Read more.

Pretreatment of grape pomace seeds with a pulsed electric field (PEF) was applied to improve the extraction yield of cold-pressed grape seed oil. The effects of different PEF conditions, electric field intensities (12.5, 14.0 and 15.6 kV/cm), and durations (15 and 30 min) on the oil chemical composition were also studied. All PEF pretreatments significantly increased the oil yield, flow rate and concentration of total sterols (p < 0.05). In addition, similar trends were observed for total tocochromanols and phenolic compounds, except for PEF pretreatment under the mildest conditions (12.5 kV/cm, 15 min) (p < 0.05). Notably, the application of 15.6 kV/cm for 30 min resulted in the highest relative increase in oil yield and flow rate (29.6% and 56.5%, respectively) and in the concentrations of total tocochromanols, nonflavonoids, and flavonoids (22.1%, 60.2% and 81.5%, respectively). In addition, the highest relative increase in the concentration of total sterols (25.4%) was achieved by applying 12.5 kV/cm for 30 min. The fatty acid composition of the grape seed oil remained largely unaffected by the PEF pretreatments. These results show that PEF pretreatment effectively improves both the yield and the bioactive properties of cold-pressed grape seed oil. Full article

(This article belongs to the Special Issue The Extraction, Characterization and Application of Functional Ingredients from Agri-Food Wastes and By-Products)

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18 pages, 4361 KiB

Open AccessArticle

In Vitro Characterization of Polysaccharides from Fresh Tea Leaves in Simulated Gastrointestinal Digestion and Gut Microbiome Fermentation

by Qiaoyi Zhou, Jinjing Gao, Xueyan Sun, Yicheng Liang, Minqi Ye, Dongxia Liang, Caijin Ling and Binghu Fang

Foods 2024, 13(10), 1561; https://doi.org/10.3390/foods13101561 - 16 May 2024

Cited by 3 | Viewed by 2020

Abstract

Tea plants have a long cultivation history in the world, but there are few studies on polysaccharides from fresh tea leaves. In this study, tea polysaccharides (TPSs) were isolated from fresh tea leaves. Then, we investigated the characteristics of TPSs during in vitro [...] Read more.

Tea plants have a long cultivation history in the world, but there are few studies on polysaccharides from fresh tea leaves. In this study, tea polysaccharides (TPSs) were isolated from fresh tea leaves. Then, we investigated the characteristics of TPSs during in vitro simulated digestion and fermentation; moreover, the effects of TPSs on gut microbiota were explored. The results revealed that saliva did not significantly affect TPSs’ molecular weight, monosaccharide composition, and reducing sugar content, indicating that TPSs cannot be digested in the oral cavity. However, TPSs were partially decomposed in the gastrointestinal tract after gastric and intestinal digestion, resulting in the release of a small amount of free glucose monosaccharides. Our in vitro fermentation experiments demonstrated that TPSs are degraded by gut microbiota, leading to short-chain fatty acid (SCFA) production and pH reduction. Moreover, TPSs increased the abundance of Bacteroides, Lactobacillus, and Bifidobacterium but reduced that of Escherichia, Shigella, and Enterococcus, demonstrating that TPSs can regulate the gut microbiome. In conclusion, TPSs are partially decomposed by gut microbiota, resulting in the production of SCFAs and the regulation of gut microbiota composition and function. Therefore, TPSs may be used to develop a prebiotic supplement to regulate the gut microbiome and improve host health. Full article

(This article belongs to the Special Issue The Extraction, Characterization and Application of Functional Ingredients from Agri-Food Wastes and By-Products)

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29 pages, 5706 KiB

Open AccessArticle

Bioactive Potential of Olive Mill Waste Obtained from Cultivars Grown in the Island of Malta

by Frederick Lia and Karen Attard

Foods 2024, 13(8), 1152; https://doi.org/10.3390/foods13081152 - 10 Apr 2024

Viewed by 2167

Abstract

This study explores the bioactive potential of olive mill waste derived from cultivars grown in the Maltese Islands through various analytical approaches. Cell culture, cell staining, allelopathic assays, shrimp brine lethality assays, and HPLC analysis were conducted to assess the efficacy and bioactivity [...] Read more.

This study explores the bioactive potential of olive mill waste derived from cultivars grown in the Maltese Islands through various analytical approaches. Cell culture, cell staining, allelopathic assays, shrimp brine lethality assays, and HPLC analysis were conducted to assess the efficacy and bioactivity of the extracts using different treatments, including methanolic extraction, acid, and alkaline hydrolysis. Notably, the results from cell lines revealed that NB4r2 cells exhibited high susceptibility to the tested extracts, with the lowest IC₅₀ recorded after 72 h of exposure. Notably, the ‘Bajda’ cultivar displayed the most effectiveness, particularly with acid hydrolysis. In allelopathic assays, higher concentrations of ‘Malti’, ‘Bidni’, and ‘Bajda’ extracts significantly inhibited lettuce seed germination. Similarly, in the brine shrimp lethality assay, higher concentrations led to increased mortality rates of Artemia salina, though rates decreased at lower concentrations. The identification of phenolic compounds found in olive mill waste was conducted using high-performance liquid chromatography (HPLC) with the use of internal standards. The identification revealed a variety of compounds, with 3-hydroxytyrosol and oleacein being present in high abundance in nearly all hydrolyzed and methanolic extracts, whereas gallic acid was found to be the least abundant. These findings highlight the rich bioactive potential of olive mill waste and provide insights into its applications in pharmaceuticals, nutraceuticals, and agriculture, emphasizing the importance of further research to fully exploit these valuable resources. Full article

(This article belongs to the Special Issue The Extraction, Characterization and Application of Functional Ingredients from Agri-Food Wastes and By-Products)

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Review

Jump to: Research

33 pages, 447 KiB

Open AccessReview

Valorization of Berry Fruit By-Products: Bioactive Compounds, Extraction, Health Benefits, Encapsulation and Food Applications

by Sandra Pedisić, Zoran Zorić, Maja Repajić, Branka Levaj, Ana Dobrinčić, Sandra Balbino, Zrinka Čošić, Verica Dragović-Uzelac and Ivona Elez Garofulić

Foods 2025, 14(8), 1354; https://doi.org/10.3390/foods14081354 - 15 Apr 2025

Viewed by 891

Abstract

The increased production of high-quality berry products in recent years has led to considerable quantities of by-products such as pomace (25–50%), which consists of skin, seeds, stems and leaves. The improper management of pomace can lead to environmental pollution and potential public health [...] Read more.

The increased production of high-quality berry products in recent years has led to considerable quantities of by-products such as pomace (25–50%), which consists of skin, seeds, stems and leaves. The improper management of pomace can lead to environmental pollution and potential public health problems due to microbial contamination, and storage causes additional processing costs. However, due to their high content of various valuable bioactive compounds (BACs), berry by-products have gained much attention as sustainable and functional ingredients with applications in the food and nutraceutical industries. The health benefits are primarily attributed to the phenolic compounds, which exhibit numerous biological activities, especially good antioxidant and antibacterial activity as well as health-promoting effects. This review summarizes the bioactive content and composition of extracts from berry by-products (genera Ribes, Rubus, Fragaria, Sambucus, Aronia and Vaccinium) obtained using advanced extraction technologies and their stabilization through sophisticated encapsulation technologies that make them suitable for various food applications. The addition of berry pomace to beverages, bakery, dairy and meat products improves sensory quality, extends shelf life, increases nutritional value and reduces the environmental footprint. This information can provide food scientists with valuable insights to evaluate the potential of berry by-products as functional ingredients with health-promoting and disease-preventing properties that create value-added products for human consumption while reducing food waste. Full article

(This article belongs to the Special Issue The Extraction, Characterization and Application of Functional Ingredients from Agri-Food Wastes and By-Products)

21 pages, 1430 KiB

Open AccessReview

Isolation of Extracellular Vesicles from Agri-Food Wastes: A Novel Perspective in the Valorization of Agri-Food Wastes and By-Products

by Raffaella Latella, Eleonora Calzoni, Lorena Urbanelli, Giada Cerrotti, Serena Porcellati, Carla Emiliani, Sandra Buratta and Brunella Tancini

Foods 2024, 13(10), 1492; https://doi.org/10.3390/foods13101492 - 11 May 2024

Cited by 7 | Viewed by 2669

Abstract

Agri-food wastes generated by industrial food processing are valorized through the extraction of biomolecules to obtain value-added products useful for various industrial applications. In the present review, we describe the valuable by-products and bioactive molecules that can be obtained from agricultural wastes and [...] Read more.

Agri-food wastes generated by industrial food processing are valorized through the extraction of biomolecules to obtain value-added products useful for various industrial applications. In the present review, we describe the valuable by-products and bioactive molecules that can be obtained from agricultural wastes and propose extracellular vesicles (EVs) as innovative nutraceutical and therapeutic compounds that could be derived from agriculture residues. To support this idea, we described the general features and roles of EVs and focused on plant-derived extracellular vesicles (PDEVs) that are considered natural carriers of bioactive molecules and are involved in intercellular communication between diverse kingdoms of life. Consistently, PDEVs exert beneficial effects (anti-inflammatory, anti-tumor, and immune-modulatory) on mammalian cells. Although this research field is currently in its infancy, in the near future, the isolation of EVs and their use as nutraceutical tools could represent a new and innovative way to valorize waste from the agri-food industry in an ecofriendly way. Full article

(This article belongs to the Special Issue The Extraction, Characterization and Application of Functional Ingredients from Agri-Food Wastes and By-Products)

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