Natural Antioxidants: Innovative Extraction and Application in Foods

A special issue of Foods (ISSN 2304-8158). This special issue belongs to the section "Food Physics and (Bio)Chemistry".

Deadline for manuscript submissions: closed (1 September 2020) | Viewed by 56215

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National Institute of Agrarian and Veterinary Research, Rua dos Lágidos, Lugar da Madalena, 4485-655 Vila do Conde, Portugal
Interests: food and food packaging analysis; food bioactives; food contaminants; mycotoxins; food packaging migration; development and validation of analytical methods for the determination of food components and food contaminants; mass spectrometry applied to food analysis; development of active packaging with antioxidant properties; edible packaging
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Dear Colleagues,

Research has devoted great attention to the study of the biological properties of plants, animal products, microorganisms, marine species, and fungi, among others, often driven by the need to discover new medicines. Many times, in order to enhance biological activities, extracts are prepared. One of the most well studied biological activities is antioxidant capacity, related to anticancer and anti-ageing properties, the improvement of immune function, and protection against cardiovascular diseases and neurological disorders. Moreover, in foods, antioxidants allow for delayed oxidation onset and enhancing food shelf life.

The changes in lifestyle patterns and world population growth demand safe, nutritious, flavourful, colourful, affordable, and convenient food, and the high-quality standards have increased the use of food additives, especially antioxidants. The effects of some food additives on human health are controversial, and synthetic food additives are often associated with potential public health risk. Therefore, there is a tendency towards substituting synthetic food additives with natural compounds.

We are organizing a Special Issue entitled “Natural Antioxidants: Innovative Extraction and Application in Foods” in the Foods (ISSN 2304-8158; CODEN: FOODBV), https://www.mdpi.com/journal/foods). With your distinguished expertise in this area, we would like to invite you to submit a paper to this Special Issue. The Special Issue focuses on the application of innovative extraction techniques for the recovery of natural antioxidants from foods, and their possible application in food industries.

Prof. Monica Rosa Loizzo
Dr. Ana Sanches Silva
Guest Editors

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Keywords

  • Antioxidants
  • Extraction
  • Incorporation of antioxidant in food matrix

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Published Papers (12 papers)

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Editorial

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4 pages, 181 KiB  
Editorial
Natural Antioxidants: Innovative Extraction and Application in Foods
by Monica Rosa Loizzo and Ana Sanches Silva
Foods 2021, 10(5), 937; https://doi.org/10.3390/foods10050937 - 25 Apr 2021
Cited by 1 | Viewed by 1984
Abstract
Research has devoted great attention to the study of the biological properties of plants, animal products, microorganisms, marine species, and fungi, among others, often driven by the need to discover new medicines [...] Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)

Research

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13 pages, 761 KiB  
Article
The Effect of Blanching on Phytochemical Content and Bioactivity of Hypochaeris and Hyoseris Species (Asteraceae), Vegetables Traditionally Used in Southern Italy
by Vincenzo Sicari, Monica R. Loizzo, Ana Sanches Silva, Rosa Romeo, Giovanni Spampinato, Rosa Tundis, Mariarosaria Leporini and Carmelo M. Musarella
Foods 2021, 10(1), 32; https://doi.org/10.3390/foods10010032 - 24 Dec 2020
Cited by 15 | Viewed by 4011
Abstract
The impact of blanching on the phytochemical content and bioactivity of Hypochaeris laevigata (HL), Hypochaeris radicata (HR), Hyoseris radiata (HRA), and Hyoseris lucida subsp. taurina (HT) leaves was studied and compared to fresh plant materials and residual blanching water. For this purpose, total [...] Read more.
The impact of blanching on the phytochemical content and bioactivity of Hypochaeris laevigata (HL), Hypochaeris radicata (HR), Hyoseris radiata (HRA), and Hyoseris lucida subsp. taurina (HT) leaves was studied and compared to fresh plant materials and residual blanching water. For this purpose, total phenols, flavonoids, carotenoids, and chlorophyll contents were quantified. The antioxidant effect was investigated by using different in vitro tests (β-carotene, ferric reducing ability power (FRAP), 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH), whereas the potential inhibitory activity of key enzymes linked to obesity was screened against lipase, α-amylase, and α-glucosidase. Generally, the phytochemical content followed the trend: fresh > blanching water > blanched samples. The same trend was observed in the antioxidant activity independently of the applied test as well as in the inhibition of lipase and carbohydrates-hydrolysing enzymes. In particular, fresh Hypochaeris laevigata (HL1) showed the lowest inhibitory concentration 50% (IC50) values of 31.3 and 42.7 μg/mL, against α-glucosidase and α-amylase, respectively, whereas fresh Hyoseris radiata (HRA1) showed the most promising hypolipidemic activity (IC50 value of 39.8 μg/mL). Collectively, these results support the health effect of these wild plants and demonstrated that blanching water should be reused in food preparation since it is a good source of bioactive compounds and its consumption should be recommended in order to increase the uptake of micronutrients. Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)
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18 pages, 3980 KiB  
Article
Effect of Microwave Pretreatment of Seeds on the Quality and Antioxidant Capacity of Pomegranate Seed Oil
by Tafadzwa Kaseke, Umezuruike Linus Opara and Olaniyi Amos Fawole
Foods 2020, 9(9), 1287; https://doi.org/10.3390/foods9091287 - 14 Sep 2020
Cited by 32 | Viewed by 4389
Abstract
Microwave pretreatment of oilseeds is a novel technique used to enhance oil nutraceutical properties. In this study, the effect of microwave pretreatment of seeds was investigated on pomegranate seed oil quality attributes including oil yield, yellowness index, refractive index, peroxide value, ρ-anisidine [...] Read more.
Microwave pretreatment of oilseeds is a novel technique used to enhance oil nutraceutical properties. In this study, the effect of microwave pretreatment of seeds was investigated on pomegranate seed oil quality attributes including oil yield, yellowness index, refractive index, peroxide value, ρ-anisidine value, total oxidation value, conjugated dienes, total phenolic content, total carotenoids content, phytosterol composition, fatty acid composition, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, and ferric reducing antioxidant power (FRAP). The seeds of three different pomegranate cultivars (‘Acco’, ‘Herskawitz’, and ‘Wonderful’) were microwave heated at 261 W for 102 s. Pomegranate seeds microwave pretreatment enhanced oil yield, yellowness index, total carotenoids content, total phenolic content, FRAP and DPPH radical scavenging capacity, despite an increase in conjugated dienes, and peroxide value. Palmitic acid, oleic acid, linoleic acid, saturated, and monosaturated fatty acids were increased after pomegranate seeds microwave pretreatment, whilst the levels of punicic acid and β-sitosterol were reduced. Nevertheless, the refractive index, the ratio of unsaturated to saturated fatty acid of the extracted oil were not significantly (p > 0.05) affected by pomegranate seeds microwave pretreatment. Principal component analysis and agglomerative hierarchical clustering established that ‘Acco’ and ‘Wonderful’ oil extracts from microwave pretreated PS exhibited better oil yield, whilst ‘Herskawitz’ oil extracts showed higher total carotenoids content, total phenolic content, and antioxidant capacity. Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)
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18 pages, 1984 KiB  
Article
Chemical Composition and Antioxidant Activity of Thyme, Hemp and Coriander Extracts: A Comparison Study of Maceration, Soxhlet, UAE and RSLDE Techniques
by Sara Palmieri, Marika Pellegrini, Antonella Ricci, Dario Compagnone and Claudio Lo Sterzo
Foods 2020, 9(9), 1221; https://doi.org/10.3390/foods9091221 - 2 Sep 2020
Cited by 79 | Viewed by 8179
Abstract
Appropriate and standardized techniques for the extraction of secondary metabolites with interesting biological activity from plants are required. In this work, a comparison of different conventional and unconventional extraction techniques (maceration—M, Soxhlet—S, ultrasound assisted extraction—UAE, and rapid solid-liquid dynamic extraction—RSLDE) was investigated. Bioactive [...] Read more.
Appropriate and standardized techniques for the extraction of secondary metabolites with interesting biological activity from plants are required. In this work, a comparison of different conventional and unconventional extraction techniques (maceration—M, Soxhlet—S, ultrasound assisted extraction—UAE, and rapid solid-liquid dynamic extraction—RSLDE) was investigated. Bioactive compounds were extracted from Thymus vulgaris L. (thyme), Cannabis sativa L. (industrial hemp) and Coriandrum sativum L. (coriander) and chemically characterized for their volatile fraction and polyphenolic content by means of gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography-ultraviolet (HPLC-UV). Linalool (48.19%, RSLDE) and carvacrol (21.30%, M) for thyme, caryophyllene (54.78%, S) and humulene (14.13%, S) for hemp, and linalool (84.16%, RSLDE) for coriander seeds were the main compounds among terpenes, while thyme was the richest source of polyphenols with rosmarinic acid (51.7 mg/g dry extract-S), apigenin (7.6 mg/g dry extract-S), and luteolin (4.1 mg/g dry extract-UAE) being the most abundant. In order to shed light on their potential as natural food preservatives, the biological activity of the extracts was assessed in terms of antioxidant activity (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid—ABTS˙+, ferric reducing antioxidant power—FRAP, 2,2-diphenyl-1-picrylhydrazyl—DPPH˙ assays) and phenolic content (Folin–Ciocâlteu method). For thyme, Soxhlet extracts showed best performances in FRAP and ABTS˙+ assays (74 mg TE/g dry extract and 134 mg TE/g dry extract, respectively), while Soxhlet and RSLDE extracts recorded similar activity in DPPH˙ (107–109 mg TE/g dry extract). For hemp and coriander, indeed, RSLDE extracts accounted for higher antioxidant activity as evidenced by FRAP (80 mg TE/g dry extract and 18 mg TE/g dry extract, respectively) and ABTS˙+ (557 mg TE/g dry extract and 48 mg TE/g dry extract, respectively) assays. With respect to DPPH˙, the best results were observed for UAE extracts (45 mg TE/g dry extract and 220 mg TE/g dry extract, respectively). Our findings suggest that all the investigated techniques are valid extraction methods to retain bioactive compounds and preserve their activity for application in food and pharmaceutical formulations. Among them, the innovative RSLDE stands out for the slightly higher antioxidant performances of the extracts, coupled with the facility of use and standardization of the extraction process. Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)
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15 pages, 1302 KiB  
Article
Organic Selenium as Antioxidant Additive in Mitigating Acrylamide in Coffee Beans Roasted via Conventional and Superheated Steam
by Ahmad K. Alafeef, Fazilah Ariffin and Musfirah Zulkurnain
Foods 2020, 9(9), 1197; https://doi.org/10.3390/foods9091197 - 29 Aug 2020
Cited by 13 | Viewed by 5213
Abstract
Selenium is an essential micronutrient with significant antioxidant activity promising in mitigating the formation of acrylamide during high-temperature roasting. In this study, green coffee beans pretreated with selenium (Se-coffee) were investigated on their selenium uptake, selenium retention in green and roasted beans, antioxidant [...] Read more.
Selenium is an essential micronutrient with significant antioxidant activity promising in mitigating the formation of acrylamide during high-temperature roasting. In this study, green coffee beans pretreated with selenium (Se-coffee) were investigated on their selenium uptake, selenium retention in green and roasted beans, antioxidant activities, and formation of acrylamide during conventional and superheated steam roasting. Comparisons were made with positive (pretreated without selenium) and negative (untreated) controls. The acrylamide formation was significantly inhibited in Se-coffee (108.9–165.3 μg/kg) compared to the positive and negative controls by 73.9% and 52.8%, respectively. The reduction of acrylamide by superheated steam roasting only observed in the untreated coffee beans (negative control) by 32.4% parallel to the increase in its antioxidant activity. Selenium pretreatment significantly increased antioxidant activity of the roasted Se-coffee beans after roasting although soaking pretreatment significantly reduced antioxidant activity in the green beans. Acrylamide reduction in the roasted coffee beans strongly correlated with the change in antioxidant capacities after roasting (∆FRAP, 0.858; ∆DPPH, 0.836). The results indicate that the antioxidant properties of the organic selenium suppressed acrylamide formation during coffee roasting. Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)
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18 pages, 1837 KiB  
Article
Antioxidant Compounds for the Inhibition of Enzymatic Browning by Polyphenol Oxidases in the Fruiting Body Extract of the Edible Mushroom Hericium erinaceus
by Seonghun Kim
Foods 2020, 9(7), 951; https://doi.org/10.3390/foods9070951 - 17 Jul 2020
Cited by 30 | Viewed by 6443
Abstract
Mushrooms are attractive resources for novel enzymes and bioactive compounds. Nevertheless, mushrooms spontaneously form brown pigments during food processing as well as extraction procedures for functional compounds. In this study, the dark browning pigment in the extract derived from the edible mushroom Hericium [...] Read more.
Mushrooms are attractive resources for novel enzymes and bioactive compounds. Nevertheless, mushrooms spontaneously form brown pigments during food processing as well as extraction procedures for functional compounds. In this study, the dark browning pigment in the extract derived from the edible mushroom Hericium erinaceus was determined to be caused by the oxidation of endogenous polyphenol compounds by the polyphenol oxidase (PPO) enzyme family. These oxidized pigment compounds were measured quantitatively using a fluorospectrophotometer and, through chelation deactivation and heat inactivation, were confirmed to be enzymatic browning products of reactions by a metalloprotein tyrosinase in the PPO family. Furthermore, a transcript analysis of the identified putative PPO-coding genes in the different growth phases showed that tyrosinase and laccase isoenzymes were highly expressed in the mushroom fruiting body, and these could be potential PPOs involved in the enzymatic browning reaction. A metabolite profiling analysis of two different growth phases also revealed a number of potential enzymatic browning substances that were grouped into amino acids and their derivatives, phenolic compounds, and purine and pyrimidine nucleobases. In addition, these analyses also demonstrated that the mushroom contained a relatively high amount of natural antioxidant compounds that can effectively decrease the browning reaction via PPO-inhibitory mechanisms that inhibit tyrosinase and scavenge free radicals in the fruiting body. Altogether, these results contribute to an understanding of the metabolites and PPO enzymes responsible for the enzymatic browning reaction of H. erinaceus. Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)
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14 pages, 1064 KiB  
Article
Impact of Stability of Enriched Oil with Phenolic Extract from Olive Mill Wastewaters
by Rosa Romeo, Alessandra De Bruno, Valeria Imeneo, Amalia Piscopo and Marco Poiana
Foods 2020, 9(7), 856; https://doi.org/10.3390/foods9070856 - 30 Jun 2020
Cited by 29 | Viewed by 3444
Abstract
The disposal of olive mill wastewaters is a considerable subject for the development of a sustainable olive oil industry considering their high content of pollutants. Nevertheless, the selective extraction of phenolic compounds from olive mill wastewaters represents a promising approach to obtain phenolics [...] Read more.
The disposal of olive mill wastewaters is a considerable subject for the development of a sustainable olive oil industry considering their high content of pollutants. Nevertheless, the selective extraction of phenolic compounds from olive mill wastewaters represents a promising approach to obtain phenolics suitable for food enrichment. This work aimed to evaluate the efficiency of phenolic extract addition (50 mg L−1), used as natural antioxidant, in sunflower oil against oxidative deterioration; to this aim, XAD-7-HP resin was tested in the recovery of phenolic compounds from olive mill wastewaters. Ultra-high performance liquid chromatography was used to evaluate the single phenols contained in the extract; the most consistent amount was detected for hydroxytyrosol (834 mg 100 mL−1). The change in the oxidation state of fortified sunflower oil was studied by measuring physicochemical (refractive index, peroxide value and oxidative resistance to degradation) and antioxidant parameters (DPPH, ABTS and ORAC assays) during 90 days of storage. Results showed an enhancement of oxidative stability of 50% in the fortified oil compared to control. Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)
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13 pages, 1467 KiB  
Article
A Novel and Simpler Alkaline Hydrolysis Methodology for Extraction of Ferulic Acid from Brewer’s Spent Grain and its (Partial) Purification through Adsorption in a Synthetic Resin
by Pedro Ideia, Ivo Sousa-Ferreira and Paula C. Castilho
Foods 2020, 9(5), 600; https://doi.org/10.3390/foods9050600 - 8 May 2020
Cited by 29 | Viewed by 4693
Abstract
This work aims to develop simpler methodologies of extracting ferulic acid (FA) from brewer’s spent grain (BSG). BSG is produced by brewing companies at high amounts all over the year and does not possess a direct application. Thus, its use as raw material [...] Read more.
This work aims to develop simpler methodologies of extracting ferulic acid (FA) from brewer’s spent grain (BSG). BSG is produced by brewing companies at high amounts all over the year and does not possess a direct application. Thus, its use as raw material for extraction of bioactive compounds has gained attention in the last years. FA has different interesting applications in cosmetics, food industry, and pharmaceutics. Several studies aim for its extraction from BSG by various methods, namely alkaline hydrolysis. In the present work, we suggest the use of autoclave to process higher amounts of BSG in a lab scale. A simplification of the regular post-hydrolysis procedures is also proposed to decrease the number of experimental steps and energy costs and to simultaneously increase the extraction yield (up to 470 mg of FA per 100 g of BSG). The adsorption of extracted FA in a synthetic resin is suggested as a partial purification method. Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)
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15 pages, 1801 KiB  
Article
Radical Scavenging and Antimicrobial Properties of Polyphenol Rich Waste Wood Extracts
by Anita Smailagić, Petar Ristivojević, Ivica Dimkić, Tamara Pavlović, Dragana Dabić Zagorac, Sonja Veljović, Milica Fotirić Akšić, Mekjell Meland and Maja Natić
Foods 2020, 9(3), 319; https://doi.org/10.3390/foods9030319 - 10 Mar 2020
Cited by 20 | Viewed by 4363
Abstract
The main focus of this study is to assess radical scavenging and antimicrobial activities of the 11 wood extracts: oak (Quercus petraea (Matt.) Liebl., Q. robur L., and Q. cerris L.), mulberry (Morus alba L.), myrobalan plum (Prunus [...] Read more.
The main focus of this study is to assess radical scavenging and antimicrobial activities of the 11 wood extracts: oak (Quercus petraea (Matt.) Liebl., Q. robur L., and Q. cerris L.), mulberry (Morus alba L.), myrobalan plum (Prunus cerasifera Ehrh.), black locust (Robinia pseudoacacia L.), and wild cherry (Prunus avium L.). High-performance thin-layer chromatography (HPTLC) provided initial phenolic screening and revealed different chemical patterns among investigated wood extracts. To identify individual compounds with radical scavenging activity DPPH-HPTLC, assay was applied. Gallic acid, ferulic and/or caffeic acids were identified as the compounds with the highest contribution of total radical scavenging activity. Principal component analysis was applied on the data set obtained from HPTLC chromatogram to classify samples based on chemical fingerprints: Quercus spp. formed separate clusters from the other wood samples. The wood extracts were evaluated for their antimicrobial activity against eight representative human and opportunistic pathogens. The lowest minimum inhibitory concentration (MIC) was recorded against Staphylococcus aureus for black locust, cherry and mulberry wood extracts. This work provided simple, low-cost and high-throughput screening of phenolic compounds and assessments of the radical scavenging properties of selected individual metabolites from natural matrix that contributed to scavenge free radicals. Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)
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9 pages, 1282 KiB  
Article
Extract from Broccoli Byproducts to Increase Fresh Filled Pasta Shelf Life
by Luisa Angiolillo, Sara Spinelli, Amalia Conte and Matteo Alessandro Del Nobile
Foods 2019, 8(12), 621; https://doi.org/10.3390/foods8120621 - 27 Nov 2019
Cited by 18 | Viewed by 3256
Abstract
The aim of the study was to evaluate the efficacy of extract from broccoli byproducts, as a green alternative to chemical preservation strategies for fresh filled pasta. In order to prove its effectiveness, three different percentages (10%, 15%, and 20% v/w [...] Read more.
The aim of the study was to evaluate the efficacy of extract from broccoli byproducts, as a green alternative to chemical preservation strategies for fresh filled pasta. In order to prove its effectiveness, three different percentages (10%, 15%, and 20% v/w) of extract were added to the filling of pasta. A shelf life test was carried out by monitoring microbiological and sensory quality. The content of phenolic compounds before and after in vitro digestion of pasta samples was also recorded. Results underlined that the addition of the natural extract helped to record a final shelf life of about 24 days, that was 18 days longer in respect to the control sample. Furthermore, results highlighted that the addition of byproducts extract to pasta also increased its phenolic content after in vitro digestion. Therefore, broccoli byproducts could be valorized for recording extracts that are able to prolong shelf life and increase the nutritional content of fresh filled pasta. Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)
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9 pages, 331 KiB  
Article
Bioactive Compounds from Norway Spruce Bark: Comparison Among Sustainable Extraction Techniques for Potential Food Applications
by Sara Spinelli, Cristina Costa, Amalia Conte, Nicola La Porta, Lucia Padalino and Matteo Alessandro Del Nobile
Foods 2019, 8(11), 524; https://doi.org/10.3390/foods8110524 - 23 Oct 2019
Cited by 24 | Viewed by 4093
Abstract
Picea abies (L.) Karst, (Norway spruce) bark, generally considered as wood industry waste, could potentially be used as a valuable source of antioxidants for food applications. In this study, supercritical fluid extraction (SFE), pressurized liquid extraction (PLE), and ultrasound-assisted extraction (UAE) were carried [...] Read more.
Picea abies (L.) Karst, (Norway spruce) bark, generally considered as wood industry waste, could potentially be used as a valuable source of antioxidants for food applications. In this study, supercritical fluid extraction (SFE), pressurized liquid extraction (PLE), and ultrasound-assisted extraction (UAE) were carried out in order to recover bioactive compounds from bark of Norway spruce. Obtained results show that PLE with ethanol as solvent was the most effective method for extracting total flavonoid compounds (21.14 ± 1.42 mg quercetin g−1 sample) and consequently exerted the highest antioxidant activity measured by 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (257.11 ± 13.31 mg Trolox g−1 sample). On the other hand, UAE extract contained the maximum phenolic concentration (54.97 ± 2.00 mg gallic acid g−1 sample) and the most interesting antioxidant activity measured by the ferric-reducing antioxidant power (580.25 ± 25.18 µmol FeSO4 g−1 sample). Additionally, PLE and UAE have demonstrated great efficiency in the extraction of trans-resveratrol, quantified by HPLC (0.19 and 0.29 mg trans-RSV g−1 sample, respectively). Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)
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Review

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22 pages, 798 KiB  
Review
A New Insight on Cardoon: Exploring New Uses besides Cheese Making with a View to Zero Waste
by Cássia H. Barbosa, Mariana A. Andrade, Fernanda Vilarinho, Isabel Castanheira, Ana Luísa Fernando, Monica Rosa Loizzo and Ana Sanches Silva
Foods 2020, 9(5), 564; https://doi.org/10.3390/foods9050564 - 2 May 2020
Cited by 26 | Viewed by 4946
Abstract
Cardoon, Cynara cardunculus L., is a perennial plant whose flowers are used as vegetal rennet in cheese making. Cardoon is native from the Mediterranean area and is commonly used in the preparation of salads and soup dishes. Nowadays, cardoon is also being exploited [...] Read more.
Cardoon, Cynara cardunculus L., is a perennial plant whose flowers are used as vegetal rennet in cheese making. Cardoon is native from the Mediterranean area and is commonly used in the preparation of salads and soup dishes. Nowadays, cardoon is also being exploited for the production of energy, generating large amount of wastes, mainly leaves. These wastes are rich in bioactive compounds with important health benefits. The aim of this review is to highlight the main properties of cardoon leaves according to the current research and to explore its potential uses in different sectors, namely the food industry. Cardoon leaves are recognized to have potential health benefits. In fact, some studies indicated that cardoon leaves could have diuretic, hepato-protective, choleretic, hypocholesterolemic, anti-carcinogenic, and antibacterial properties. Most of these properties are due to excellent polyphenol profiles, with interesting antioxidant and antimicrobial activities. These findings indicate that cardoon leaves can have new potential uses in different sectors, such as cosmetics and the food industry; in particular, they can be used for the preparation of extracts to incorporate into active food packaging. In the future, these new uses of cardoon leaves will allow for zero waste of this crop. Full article
(This article belongs to the Special Issue Natural Antioxidants: Innovative Extraction and Application in Foods)
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