Agri-Food Wastes as Natural Source of Bioactive Antioxidants

A special issue of Antioxidants (ISSN 2076-3921). This special issue belongs to the section "Natural and Synthetic Antioxidants".

Deadline for manuscript submissions: closed (30 June 2022) | Viewed by 60216

Special Issue Editors


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

E-Mail Website
Guest Editor
Department for Life Quality Studies, Alma Mater Studiorum-University of Bologna, Corso D’Augusto 237, 47921 Rimini, Italy
Interests: nutritional biochemistry; neurodegenerative diseases; oxidative stress; inflammation; nutraceuticals; ageing
Special Issues, Collections and Topics in MDPI journals

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,

The agri-food industry produces a large amount of organic waste, constituting skins, peels, seeds, leaves, and other inedible fractions that are usually underutilized and cause serious problems for the environment. In the past, agri-food wastes were used to obtain products with low added value. At present, the circular economy offers various tools to recover waste, and one of the best alternatives includes transforming them into high-commercial-value products such as drugs, nutraceuticals, and cosmeceuticals. The broad presence of antioxidants in the plant kingdom and, therefore, in agri-food waste has led to an increase in interest in their recovery and further exploitation. In this regard, agri-food by-products represent a massive and low-cost source of natural bioactive compounds. To effectively recover these, it is necessary to develop green and sustainable alternatives to conventional extraction methods to increase the extraction yield and decrease the extraction time and solvent consumption.

Therefore, this Special Issue will collect research papers and reviews on the in vitro and in vivo bioactivity of antioxidant compounds from agri-food by-products, considering the different green extraction techniques used to obtain them from waste biomasses, and emphasizing their ability to modulate the complex signaling crosstalk underpinning chronic/degenerative disease development and progression.

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 100 words) can be sent to the Editorial Office for announcement on this website.

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 byproducts
  • Agri-food waste
  • Nutraceuticals
  • Functional foods
  • Essential oils
  • Bioactive compounds
  • Phytochemicals
  • Health effects
  • Green extraction

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.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

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

Published Papers (19 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Editorial

Jump to: Research, Review

7 pages, 237 KiB  
Editorial
Agri-Food Wastes as Natural Source of Bioactive Antioxidants
by Silvana Hrelia, Cristina Angeloni and Maria Cristina Barbalace
Antioxidants 2023, 12(2), 351; https://doi.org/10.3390/antiox12020351 - 2 Feb 2023
Cited by 4 | Viewed by 1780
Abstract
Nowadays, the health of the ecosystem and quality of life are jeopardized by the growing quantities of waste that are released into the environment [...] Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)

Research

Jump to: Editorial, Review

18 pages, 4662 KiB  
Article
Targeted UHPLC-MS Analysis Reveals Disparate Polyphenol Composition and Concentration in Muscadine Grape Supplements with Proportional Antioxidant Activity
by Mark C. Chappell, Aja V. Duncan, Ana Clara Melo, Christopher L. Schaich, Nancy T. Pirro, Debra I. Diz, E. Ann Tallant and Patricia E. Gallagher
Antioxidants 2022, 11(11), 2117; https://doi.org/10.3390/antiox11112117 - 27 Oct 2022
Cited by 4 | Viewed by 1875
Abstract
Muscadine grape supplements (MGS) with high polyphenol content are a potential therapeutic option to combat oxidative stress; however, the precise identity and concentration of individual phenolics in commercially processed MGSs is not well defined. We probed for 17 phenolic compounds by ultra-high pressure [...] Read more.
Muscadine grape supplements (MGS) with high polyphenol content are a potential therapeutic option to combat oxidative stress; however, the precise identity and concentration of individual phenolics in commercially processed MGSs is not well defined. We probed for 17 phenolic compounds by ultra-high pressure liquid chromatography and mass spectroscopy from distinct lots of four commercially processed MGSs composed of MG seed and/or skin waste products. The total phenolic content (TPC) and antioxidant capacity were highest in a dried water-extract MGS as compared to three ground seed and/or skin products. The TPC was not different between MGS lots from individual companies and remained stable for 3 years without microbial contamination. The extract MGS had the highest concentration of epicatechin, ellagic acid, gallic acid, procyanidin B2, catechin and catechin gallate compared to the other supplements. Only ellagic acid and gallic acid were detected in all four MGSs, while catechin and catechin gallate were below detection in two supplements. Based on gram weight, only the extract MGS prevented the angiotensin II-induced increase in malondialdehyde and 4-hydroxynonenol in rat H9c2 cardiomyocytes as well as upregulated superoxide dismutase and catalase. This study demonstrates that commercial MGSs differ in phenolic composition and concentration, resulting in disparate antioxidant activity. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Graphical abstract

15 pages, 1356 KiB  
Article
Optimization of Phlorizin Extraction from Annurca Apple Tree Leaves Using Response Surface Methodology
by Maria Maisto, Vincenzo Piccolo, Ettore Novellino, Elisabetta Schiano, Fortuna Iannuzzo, Roberto Ciampaglia, Vincenzo Summa and Gian Carlo Tenore
Antioxidants 2022, 11(10), 1933; https://doi.org/10.3390/antiox11101933 - 28 Sep 2022
Cited by 16 | Viewed by 2083
Abstract
Phlorizin is a plant-derived molecule with relevant anti-diabetic activity, making this compound a potential functional component in nutraceutical formulations for the management of glycemia. It is noteworthy that promising sources for the extraction of phlorizin include apple tree leaves, a by-product of apple [...] Read more.
Phlorizin is a plant-derived molecule with relevant anti-diabetic activity, making this compound a potential functional component in nutraceutical formulations for the management of glycemia. It is noteworthy that promising sources for the extraction of phlorizin include apple tree leaves, a by-product of apple fruit production. The main aim of this study was to optimize the extraction process of phlorizin from Annurca apple tree leaves (AALs) using response surface methodology (RSM), and to determine the potential nutraceutical application of the obtained extract. The results of the RSM analysis indicate a maximum phlorizin yield of 126.89 ± 7.579 (mg/g DW) obtained under the following optimized conditions: MeOH/H2O, 80:20 + 1% HCOOH as the extraction solvent; 37.7 °C as the extraction temperature; and 170 min as the time of extraction. The HPLC-DAD-HESI-MS/MS analysis performed on the extract obtained under such conditions, named optimized Annurca apple leaves extract (OAALE), led to the identification of twenty-three phenolic molecules, with fifteen of them quantified. To explore the nutraceutical potential of OAALE, the in vitro antioxidant activity was evaluated by DPPH, ABTS, and FRAP assays, resulting in 21.17 ± 2.30, 38.85 ± 0.69, and 34.14 ± 3.8 μmol Trolox equivalent/g of extract, respectively. Moreover, the IC50 of 0.330 mg/mL obtained from the advanced glycation end-product inhibition assay, further supported the antidiabetic potential of OAALE. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Figure 1

10 pages, 1811 KiB  
Article
Free and Bound Phenolic Compounds Present in Orange Juice By-Product Powder and Their Contribution to Antioxidant Activity
by María del Mar Camacho, Mónica Zago, Eva García-Martínez and Nuria Martínez-Navarrete
Antioxidants 2022, 11(9), 1748; https://doi.org/10.3390/antiox11091748 - 3 Sep 2022
Cited by 9 | Viewed by 2333
Abstract
Interest in fruit/vegetable consumption is not always linked to a particular diet but rather derives from their high antioxidant activity (AOA), with potential health benefits provided, in part, by polyphenols. Although phenols can be found in free form (FP) or bound to plant [...] Read more.
Interest in fruit/vegetable consumption is not always linked to a particular diet but rather derives from their high antioxidant activity (AOA), with potential health benefits provided, in part, by polyphenols. Although phenols can be found in free form (FP) or bound to plant tissues (BP), the experimental methodology most frequently used for the quantification of total phenols (TP) is based on the extraction of a portion of FP, which may justify the lack of correlation often found between them and AOA. In this context, four successive extractions were performed to obtain FP and BP of powdered orange juice by-product, and their contribution to the AOA was studied. The first extract (MeOH, 30 °C) can be assumed to be one of the conventional methods for the quantification of TP. Re-extraction with MeOH (60 °C) afforded the FP. Two subsequent basic and acidic extractions yielded the BP. Although the FPs were the most abundant, the AOA (DPPH method) of the last fraction of BP was of the same order found in the first fraction of FP. This highlights the interest in extracting the BP from the by-product of orange juice if its antioxidant capacity is to be exploited. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Figure 1

17 pages, 2632 KiB  
Article
Optimization of Extraction and HPLC–MS/MS Profiling of Phenolic Compounds from Red Grape Seed Extracts Using Conventional and Deep Eutectic Solvents
by Nevena Dabetic, Vanja Todorovic, Andjelija Malenovic, Sladjana Sobajic and Bojan Markovic
Antioxidants 2022, 11(8), 1595; https://doi.org/10.3390/antiox11081595 - 18 Aug 2022
Cited by 14 | Viewed by 2869
Abstract
Winemaking generates large quantities of grape waste consisting of seeds, skin and stalks. Given that grape seeds are a rich source of different bioactive compounds, the main goal of this research was to optimize grape seed phenol extraction using a Box–Behnken design. The [...] Read more.
Winemaking generates large quantities of grape waste consisting of seeds, skin and stalks. Given that grape seeds are a rich source of different bioactive compounds, the main goal of this research was to optimize grape seed phenol extraction using a Box–Behnken design. The following conditions were derived from the optimization process: sample:solvent ratio of 1:10 w/v, extraction time of 30 min and extraction temperature of 50 °C. In addition, a sustainable (green) approach for obtaining extracts was developed by comparing choline chloride:citric acid-ChCit (natural deep eutectic solvent (NADES)) and ethanol extraction methods with respect to phenol profiles and antioxidant activity. This study was conducted on seeds from eight different red grape varieties. Phenolic acids, flavan-3-ols and procyanidins were characterized using HPLC–MS/MS, and the concentration of procyanidin B1 was above 1 mg/g of dry weight in all analyzed samples. The contents of all phenol classes and antioxidant activities were found to not differ significantly between the solvents, but NADES was found to offer valuable advantages. Importantly, ChCit showed a strong affinity toward procyanidins and a strong correlation between antioxidant activity and quantified phenolic compounds. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Graphical abstract

15 pages, 2893 KiB  
Article
The Effect of High-Intensity Ultrasound and Natural Oils on the Extraction and Antioxidant Activity of Lycopene from Tomato (Solanum lycopersicum) Waste
by Gieraldin Campos-Lozada, Xóchitl Alejandra Pérez-Marroquín, Graciela Callejas-Quijada, Rafael G. Campos-Montiel, Alejandro Morales-Peñaloza, Arely León-López and Gabriel Aguirre-Álvarez
Antioxidants 2022, 11(7), 1404; https://doi.org/10.3390/antiox11071404 - 20 Jul 2022
Cited by 12 | Viewed by 3301
Abstract
The extraction of lycopene was carried out with three types of vegetable oils (grape, extra virgin olive, and peanut) by means of two methods: agitation and high-intensity ultrasound with a frequency of 20 kHz at an amplitude of 80% with periods of 40 [...] Read more.
The extraction of lycopene was carried out with three types of vegetable oils (grape, extra virgin olive, and peanut) by means of two methods: agitation and high-intensity ultrasound with a frequency of 20 kHz at an amplitude of 80% with periods of 40 s of sonication for 20 min at a temperature of 40 °C. The antioxidant determination by inhibition of ABTS and DPPH radicals showed no significant differences (p > 0.05) for inhibition of the ABTS radical in native oils and oils with lycopene. However, the radical DPPH showed that the native oils presented significant differences (p ≤ 0.05) compared to the samples with lycopene. FTIR spectra revealed the characteristic functional groups of lycopene exhibiting two characteristic peaks at 2923 cm−1 and 2957 cm−1. The DSC thermograms showed that the higher the degree of oil unsaturation, the lower the melting temperatures. Olive oil was the least unsaturated with the highest amount of oleic fatty acid. Grapeseed oil reported the lowest melting temperature at around −24.64 °C. Extra virgin olive oil showed the lightest values (L* = 41.08 ± 0.45) of brightness, and the peanut oil with lycopene was the darkest (L* = 16.72 ± 0.05). The extraction of lycopene from organic wastes treated with agitation and ultrasound was satisfactory reducing the use of conventional solvents. However, extraction with olive oil under agitation showed the best results. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Graphical abstract

15 pages, 2686 KiB  
Article
Differences in Antioxidant Potential of Allium cepa Husk of Red, Yellow, and White Varieties
by Irina Chernukha, Nadezhda Kupaeva, Elena Kotenkova and Daniil Khvostov
Antioxidants 2022, 11(7), 1243; https://doi.org/10.3390/antiox11071243 - 24 Jun 2022
Cited by 12 | Viewed by 2396
Abstract
The effective management of agro-industry organic waste for developing high-commercial-value products is a promising facet of the circular economy. Annually, more than 550,000 tons of waste that is potentially rich in biologically active substances is generated worldwide while processing onions (Allium cepa [...] Read more.
The effective management of agro-industry organic waste for developing high-commercial-value products is a promising facet of the circular economy. Annually, more than 550,000 tons of waste that is potentially rich in biologically active substances is generated worldwide while processing onions (Allium cepa L.). The antioxidant potential of red, yellow, and white onion husks was studied using FRAP, ORAC, chemiluminescence, and UPLC-ESI-Q-TOF-MS analysis methods. The extraction of phenolic compounds from onion husks was more effective when using an aqueous solution of 70% ethanol as compared with water. Ethanolic extract from red onion husks exhibited the highest TACORAC and TACFRAP values, averaging 2017.34 µmol-equiv. Trolox/g raw material and 2050.23 µmol-equiv. DQ/g raw material, respectively, while the white onion exhibited much lower levels of antioxidants. According to the chemiluminescence results, it was determined that the red and yellow onion husks contained antioxidants of three types of power, while white onion husks only contained medium and weak types. The highest content of flavonoids was found in red onion husks, averaging 1915.90 ± 9.92 µg-eq. DQ/g of raw material and 321.42 ± 2.61 µg-eq. DQ/g of raw material for ethanol and water, respectively, while yellow onion husks exhibited 544.06 ± 2.73 µg-eq. DQ/g of raw material and 89.41 ± 2.08 for ethanol and water, respectively. Quercetin and its glycosides were the most representative flavonoids, and a number of substances with different pharmacological and biological properties were also identified. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Figure 1

13 pages, 884 KiB  
Article
Anthocyanins Found in Pinot Noir Waste Induce Target Genes Related to the Nrf2 Signalling in Endothelial Cells
by Jesús Herrera-Bravo, Jorge F. Beltrán, Nolberto Huard, Kathleen Saavedra, Nicolás Saavedra, Marysol Alvear, Fernando Lanas and Luis A. Salazar
Antioxidants 2022, 11(7), 1239; https://doi.org/10.3390/antiox11071239 - 24 Jun 2022
Cited by 12 | Viewed by 2182
Abstract
Grape pomace is a source of anthocyanins, which can prevent cardiovascular diseases due to their antioxidant properties. Anthocyanin activity is associated with the ability to regulate oxidative stress through the transcription factor Nrf2. Thus, the present study aimed to evaluate if the anthocyanins [...] Read more.
Grape pomace is a source of anthocyanins, which can prevent cardiovascular diseases due to their antioxidant properties. Anthocyanin activity is associated with the ability to regulate oxidative stress through the transcription factor Nrf2. Thus, the present study aimed to evaluate if the anthocyanins found in Pinot noir pomace extract can affect the target genes related to the Nrf2 signalling pathway in endothelial cells. Our results highlight that the predominant anthocyanin in the Pinot noir pomace extract was malvidin-3-glucoside (3.7 ± 2.7 Eq. Malv-3-glu/kg). Molecular docking indicated that cyanidin-3-glucoside (−6.9 kcal/mol), malvidin-3-glucoside (−6.6 kcal/mol) and peonidin-3-glucoside (−6.6 kcal/mol) showed the highest affinities for the binding sites of the BTB domains in Keap1, suggesting that these components may modify the interaction of this protein with Nrf2. In addition, when HUVEC cells were exposed to different concentrations of Pinot noir pomace extract (100 µg/mL, 200 µg/mL, and 400 µg/mL), no changes in Nrf2 gene expression were observed. However, the gene expression of HO-1 and NQO1, which are in the signalling pathway of this transcription factor, increased according the concentrations of the extract (p = 0.0004 and p = 0.0084, respectively). In summary, our results show that anthocyanins play a very important role in Nrf2 activation and release, while at the same time not promoting its transcription. These preliminary results strongly suggest that the Pinot noir pomace extract can serve as a potent bioactive component source that protects cells against oxidative stress. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Figure 1

14 pages, 3516 KiB  
Article
Antiulcer Potential of Psidium guajava Seed Extract Supported by Metabolic Profiling and Molecular Docking
by Nourhan Hisham Shady, Hend Samy Abdullah, Sherif A. Maher, Amgad Albohy, Mahmoud A. Elrehany, Fatma Alzahraa Mokhtar, Hesham Farouk Oraby, Ahmed M. Shawky and Usama Ramadan Abdelmohsen
Antioxidants 2022, 11(7), 1230; https://doi.org/10.3390/antiox11071230 - 23 Jun 2022
Cited by 11 | Viewed by 2409
Abstract
One of the most severe human health problems is gastric ulceration. The main aim of our study is to explore the gastroprotective effect of the Psidium guajava seeds extract (PGE). Metabolic profiling based on LC-HRMS for the extract led to the dereplication of [...] Read more.
One of the most severe human health problems is gastric ulceration. The main aim of our study is to explore the gastroprotective effect of the Psidium guajava seeds extract (PGE). Metabolic profiling based on LC-HRMS for the extract led to the dereplication of 23 compounds (123). We carried out a gastric ulcer model induced by indomethacin in male albino rats in vivo and the extract of PGE was investigated at a dose of 300 mg/kg in comparison to cimetidine (100 mg/kg). Furthermore, the assessment of gastric mucosal lesions and histopathology investigation of gastric tissue was done. It has been proved that Psidium guajava seeds significantly decreased the ulcer index and protected the mucosa from lesions. The antiulcer effect of Psidium guajava seed extract, which has the power of reducing the ensuing inflammatory reactions, can counteract the inflammation induced by indomethacin by the downregulation of relative genes expression (IL-1β, IL-6, and TNF-α). Moreover, PGE significantly downregulated the increased COX-2, TGF-β, and IGF-1 relative genes expression, confirming its beneficial effect in ulcer healing. Moreover, the possible PGE antioxidant potential was determined by in vitro assays using hydrogen peroxide and superoxide radical scavenging and revealed high antioxidant potential. Additionally, on the putatively annotated metabolites, an in silico study was conducted, which emphasized the extract’s antiulcer properties might be attributed to several sterols such as stigmasterol and campesterol. The present study provided evidence of Psidium guajava seeds considered as a potential natural gastroprotective agent. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Figure 1

18 pages, 2788 KiB  
Article
Liquid Chromatography–High-Resolution Mass Spectrometry (LC-HRMS) Profiling of Commercial Enocianina and Evaluation of Their Antioxidant and Anti-Inflammatory Activity
by Larissa Della Vedova, Giulio Ferrario, Francesca Gado, Alessandra Altomare, Marina Carini, Paolo Morazzoni, Giancarlo Aldini and Giovanna Baron
Antioxidants 2022, 11(6), 1187; https://doi.org/10.3390/antiox11061187 - 16 Jun 2022
Cited by 14 | Viewed by 3444
Abstract
Enocianina is an anthocyanin-rich extract obtained from grape pomace. It is widely used as a colorant in the food industry and, in addition to anthocyanins, it also contains a variety of polyphenols. To understand whether enocianina, besides its coloring effect, may offer potential [...] Read more.
Enocianina is an anthocyanin-rich extract obtained from grape pomace. It is widely used as a colorant in the food industry and, in addition to anthocyanins, it also contains a variety of polyphenols. To understand whether enocianina, besides its coloring effect, may offer potential health benefit applications, we aimed to fully characterize the profile of four commercial enocianinas and assess their radical scavenging, enzymatic, antioxidant, and anti-inflammatory activities. LC-ESI-MS/MS analysis identified 90 phytochemicals. The relative content of each anthocyanin was assessed by a semi-quantitative analysis, with malvidin derivatives being the most abundant. UV-VIS spectroscopy detected total amounts of polyphenols and anthocyanins of 23% and 3.24%, respectively, indicating that anthocyanins represent a minor fraction of total polyphenols. Multiple linear regression analysis indicated that the radical scavenging activity is related to the total polyphenol content and not to anthocyanins. All four enocianinas dose-dependently activate Nrf2, and such activity was correlated with catechol-containing polyphenol content. Finally, all enocianinas showed dose-dependent anti-inflammatory activity, which at the highest concentrations tested was closely related to the total polyphenol content and was explained by radical scavenging, Nrf2 activation, and other mechanisms related to the polyphenolic components. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Graphical abstract

25 pages, 2156 KiB  
Article
Valorization of Aloe vera Skin By-Products to Obtain Bioactive Compounds by Microwave-Assisted Extraction: Antioxidant Activity and Chemical Composition
by Ignacio Solaberrieta, Alfonso Jiménez and María Carmen Garrigós
Antioxidants 2022, 11(6), 1058; https://doi.org/10.3390/antiox11061058 - 26 May 2022
Cited by 27 | Viewed by 4360
Abstract
Aloe vera skin (AVS) is a major by-product of Aloe processing plants all over the world. In this study, response surface methodology was used to optimize microwave-assisted extraction (MAE) of bioactive compounds from AVS. The influence of extraction parameters, such as ethanol concentration [...] Read more.
Aloe vera skin (AVS) is a major by-product of Aloe processing plants all over the world. In this study, response surface methodology was used to optimize microwave-assisted extraction (MAE) of bioactive compounds from AVS. The influence of extraction parameters, such as ethanol concentration (%Et), extraction temperature (T), time (t) and solvent volume (V), on extraction yield (Y), total phenolic content (TPC), antioxidant activity (DPPH and FRAP methods) and aloin content, was studied. Optimum extraction conditions were determined as 80% ethanol, 80 °C, 36.6 min and 50 mL and optimized extracts showed interesting contents of polyphenols and antioxidant performance. The phenolic profile was determined by HPLC-DAD/MS and some major phenolic compounds, such as aloin A, aloin B, aloesin, aloe-emodin, aloeresin D, orientin, cinnamic acid and chlorogenic acid, were quantified while eight other compounds were tentatively identified. Moreover, structural and thermal properties were studied by FTIR and TGA analyses, respectively. The obtained results suggested the potential of AVS as a promising source of bioactive compounds, thus increasing the added value of this agricultural waste. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Graphical abstract

15 pages, 1959 KiB  
Article
Bioactive Compound, Antioxidant, and Radical Scavenging Activity of Some Plant Aqueous Extracts for Enhancing Shelf Life of Cold-Stored Rabbit Meat
by Huda Abdalrahman Al Jumayi, Ayman Younes Allam, Alaa El-Dein El-Beltagy, Eman Hassan Algarni, Samy F. Mahmoud and Amin Abd El Halim Kandil
Antioxidants 2022, 11(6), 1056; https://doi.org/10.3390/antiox11061056 - 26 May 2022
Cited by 16 | Viewed by 3101
Abstract
The potential radical scavenging, antioxidant activities (DPPH and ABTS) and bioactive constituents of several plant aqueous extracts (Curcuma longa, CL; Myristica fragrans, MF; Zingiber officinale, ZO; Cymbopogon citratus, CC and Thymus vulgaris, TV as well as their [...] Read more.
The potential radical scavenging, antioxidant activities (DPPH and ABTS) and bioactive constituents of several plant aqueous extracts (Curcuma longa, CL; Myristica fragrans, MF; Zingiber officinale, ZO; Cymbopogon citratus, CC and Thymus vulgaris, TV as well as their mixture) were investigated. The effect of these extracts on quality aspects (sensory characteristic, color traits, and Thiobarbituric acid) of rabbit meat during a 16-day cold (4 ± 2 °C) storage were investigated. Total phenolics and flavonoid contents of all extracts ranged from 13.27 ± 0.57 to 25.23 ± 0.49 mg GAE/g and 6.57 ± 0.22 to 13.24 ± 0.19 mg quercetin/g, respectively. The aqueous extract of MF had the highest (p ≤ 0.05) ABTS scavenging activity (4.55 μ mol Te/g dry extract), whereas the highest (p < 0.05) DPPH scavenging activity was detected in ZO extract (9.32 μ mol Te/g dry extract). Identification of extracts’ bioactive compounds by GC-MS revealed that Eugenol (34.51%), Cinnamaldehyde (44.71%), Carvacrol (40.49%), Eicosane aldehyde (31.73%), and thymol (50.04%) are the first abundant bioactive compounds of CL, MF, ZO, CC, and TV aqueous extracts, respectively. Generally, the thiobarbituric acid reactive substances (TBARS) of all cold stored rabbit meat increased (p < 0.05) by increasing the storage time. The lowest TBARS values were detected for the samples treated with 0.2% of plant extracts mixture, which increased the shelf life of cold-stored rabbits by 50%. Significant (p < 0.05) increases in both L* and b* were observed with extended storage time. Meanwhile, the redness of the cold stored rabbit meat had an opposite trend. Treating the cold stored rabbit meat with 0.2% of the extract’s mixture doubled the storage time with acceptable odor and taste. The results indicated that the studied plant extracts may be effective against rancidity and may be used as a natural antioxidant to prolong the shelf life of cold-stored rabbit meat. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Figure 1

23 pages, 1186 KiB  
Article
Biological Evaluation of Avocado Residues as a Potential Source of Bioactive Compounds
by Alejandro Rojas-García, Eduardo Fuentes, María de la Luz Cádiz-Gurrea, Lyanne Rodriguez, María del Carmen Villegas-Aguilar, Iván Palomo, David Arráez-Román and Antonio Segura-Carretero
Antioxidants 2022, 11(6), 1049; https://doi.org/10.3390/antiox11061049 - 25 May 2022
Cited by 27 | Viewed by 5354
Abstract
Avocado seed and peel are the main by-products from avocado industrialisation, and account for nearly 30% of fruit weight. Although they are usually discarded, their high phenolic content has been deeply associated with several nutritional and functional benefits. Thus, for a comprehensive analytical [...] Read more.
Avocado seed and peel are the main by-products from avocado industrialisation, and account for nearly 30% of fruit weight. Although they are usually discarded, their high phenolic content has been deeply associated with several nutritional and functional benefits. Thus, for a comprehensive analytical evaluation of both semi-industrial extracts, various steps have been developed: tentative characterisation and quantification of the phenolic composition using HPLC-ESI-qTOF-MS, determination of TPC and antioxidant activity by Folin–Ciocalteu, FRAP, TEAC and ORAC methods, evaluation of scavenging capacity against different ROS and measurement of the enzymatic inhibitory potential against potentially harmful enzymes. Finally, their bioactive potential was tested in a human platelet model where antiaggregatory activity was measured. Hence, 48 different compounds were identified, where flavonoids and procyanidins were the most representative groups. The higher TPC was found in avocado peel extract (190 ± 3 mg/g), which showed more antioxidant power and more capacity to decrease ROS generation than seed extract (60 ± 2 mg/g). In addition, both extracts showed enzymatic inhibition, especially against hyaluronidase, xanthine oxidase and acetylcholinesterase. Lastly, avocado peel was proven to inhibit platelet aggregation with significant results at 1, 0.75 and 0.5 mg/mL, where the extract showed reducing effects on agonists’ expression such as p-selectin or GPIIb/IIIa complex. These results demonstrate that both semi-industrial extracts—above all, avocado peel—have an interesting potential to be exploited as a natural by-product with antioxidant properties with multiple applications for the prevention of different pathologies. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Figure 1

20 pages, 6230 KiB  
Article
Antioxidant and Wound Healing Potential of Vitis vinifera Seeds Supported by Phytochemical Characterization and Docking Studies
by Tarfah Al-Warhi, Eman Maher Zahran, Samy Selim, Mohammad M. Al-Sanea, Mohammed M. Ghoneim, Sherif A. Maher, Yaser A. Mostafa, Faisal Alsenani, Mahmoud A. Elrehany, Mohammed S. Almuhayawi, Soad K. Al Jaouni, Usama Ramadan Abdelmohsen and Abeer H. Elmaidomy
Antioxidants 2022, 11(5), 881; https://doi.org/10.3390/antiox11050881 - 29 Apr 2022
Cited by 28 | Viewed by 3693
Abstract
This study explored the in vivo wound healing potential of Vitis vinifera seed extract using an excision wound model with focus on wound healing molecular targets including TGFBR1, VEGF, TNF-α, and IL-1β. The wound healing results revealed that V. [...] Read more.
This study explored the in vivo wound healing potential of Vitis vinifera seed extract using an excision wound model with focus on wound healing molecular targets including TGFBR1, VEGF, TNF-α, and IL-1β. The wound healing results revealed that V. vinifera seed extract enhanced wound closure rates (p < 0.001), elevated TGF-β and VEGF levels, and significantly downregulated TNF-α and IL-1β levels in comparison to the Mebo®-treated group. The phenotypical results were supported by biochemical and histopathological findings. Phytochemical investigation yielded a total of 36 compounds including twenty-seven compounds (127) identified from seed oil using GC-MS analysis, along with nine isolated compounds. Among the isolated compounds, one new benzofuran dimer (28) along with eight known ones (2936) were identified. The structure of new compound was elucidated utilizing 1D/2D NMR, with HRESIMS analyses. Moreover, molecular docking experiments were performed to elucidate the molecular targets (TNF-α, TGFBR1, and IL-1β) of the observed wound healing activity. Additionally, the in vitro antioxidant activity of V. vinifera seed extract along with two isolated compounds (ursolic acid 34, and β-sitosterol-3-O-glucopyranoside 36) were explored. Our study highlights the potential of V. vinifera seed extract in wound repair uncovering the most probable mechanisms of action using in silico analysis. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Figure 1

19 pages, 2828 KiB  
Article
Bio-Waste Products of Mangifera indica L. Reduce Adipogenesis and Exert Antioxidant Effects on 3T3-L1 Cells
by Giovanni Pratelli, Daniela Carlisi, Antonella D’Anneo, Antonella Maggio, Sonia Emanuele, Antonio Palumbo Piccionello, Michela Giuliano, Anna De Blasio, Giuseppe Calvaruso and Marianna Lauricella
Antioxidants 2022, 11(2), 363; https://doi.org/10.3390/antiox11020363 - 11 Feb 2022
Cited by 20 | Viewed by 3151
Abstract
Several studies highlighted the beneficial value of natural compounds in the prevention and treatment of obesity. Here, we investigated the anti-obesity effects of extracts of peel and seed of mango (Mangifera indica L.) cultivated in Sicily (Italy) in 3T3-L1 cells. Mango Peel [...] Read more.
Several studies highlighted the beneficial value of natural compounds in the prevention and treatment of obesity. Here, we investigated the anti-obesity effects of extracts of peel and seed of mango (Mangifera indica L.) cultivated in Sicily (Italy) in 3T3-L1 cells. Mango Peel (MPE) and Mango Seed (MSE) extracts at a 100 µg/mL concentration significantly reduced lipid accumulation and triacylglycerol contents during 3T3-L1 adipocyte differentiation without toxicity. HPLC-ESI-MS analysis showed that both the extracts contain some polyphenolic compounds that can account for the observed biological effects. The anti-adipogenic effect of MPE and MSE was the result of down-regulation of the key adipogenic transcription factor PPARγ and its downstream targets FABP4/aP2, GLUT4 and Adipsin, as well SREBP-1c, a transcription factor which promotes lipogenesis. In addition, both MPE and MSE significantly activated AMPK with the consequent inhibition of Acetyl-CoA-carboxylase (ACC) and up-regulated PPARα. The addition of compound C, a specific AMPK inhibitor, reduced the effects of MPE and MSE on AMPK and ACC phosphorylation, suggesting a role of AMPK in mediating MPE and MSE anti-lipogenic effects. Notably, MPE and MSE possess an elevated radical scavenging activity, as demonstrated by DPPH radical scavenging assay, and reduced ROS content produced during adipocyte differentiation. This last effect could be a consequence of the increase in the antioxidant factors Nrf2, MnSOD and HO-1. In conclusion, MPE and MSE possesses both anti-adipogenic and antioxidant potential, thus suggesting that the bio-waste products of mango are promising anti-obesity natural compounds. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Graphical abstract

13 pages, 302 KiB  
Article
Chemical Composition of Green Pea (Pisum sativum L.) Pods Extracts and Their Potential Exploitation as Ingredients in Nutraceutical Formulations
by Luigi Castaldo, Luana Izzo, Anna Gaspari, Sonia Lombardi, Yelko Rodríguez-Carrasco, Alfonso Narváez, Michela Grosso and Alberto Ritieni
Antioxidants 2022, 11(1), 105; https://doi.org/10.3390/antiox11010105 - 31 Dec 2021
Cited by 18 | Viewed by 4760
Abstract
Agro-industrial wastes contain a large number of important active compounds which can justify their use as innovative ingredients in nutraceutical products. This study aimed to provide a complete analysis of active molecules, namely (poly)phenols in pea pods water-based extracts, through a UHPLC-Q-Orbitrap HRMS [...] Read more.
Agro-industrial wastes contain a large number of important active compounds which can justify their use as innovative ingredients in nutraceutical products. This study aimed to provide a complete analysis of active molecules, namely (poly)phenols in pea pods water-based extracts, through a UHPLC-Q-Orbitrap HRMS methodology. Data showed that 5-caffeoylquinic acid, epicatechin, and hesperidin were the most relevant (poly)phenols found in the assayed extracts, with a mean value of 59.87, 29.46, and 19.94 mg/100 g, respectively. Furthermore, changes in antioxidant capacity and bioaccessibility of total phenolic compounds (TPC) after the simulated gastrointestinal (GI) process were performed using spectrophotometric assays (FRAP, DPPH, ABTS, and TPC by Folin-Ciocalteu). The acid-resistant capsules (ARC) and the non-acid resistant capsules (NARC) containing the pea pod extract underwent simulated GI digestion. The results suggested that the ARC formulations were able to preserve the active compounds along the simulated GI process, highlighting a higher TPC value and antioxidant capacity than the NARC formulations and the not-encapsulated extracts. Hence, the pea pods water-based extracts could be utilized as a potential alternative source of active compounds, and the use of ARC could represent a suitable nutraceutical formulation to vehiculate the active compounds, protecting the chemical and bioactive properties of (poly)phenols. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)

Review

Jump to: Editorial, Research

25 pages, 376 KiB  
Review
The Greening of Anthocyanins: Eco-Friendly Techniques for Their Recovery from Agri-Food By-Products
by Mariacaterina Lianza, Lorenzo Marincich and Fabiana Antognoni
Antioxidants 2022, 11(11), 2169; https://doi.org/10.3390/antiox11112169 - 1 Nov 2022
Cited by 15 | Viewed by 2295
Abstract
In recent years, several steps forward have been made toward a more sustainable approach for the extraction of bioactive compounds from plant materials based on the application of green extraction principles. It is currently recognized that waste and by-products deriving from agriculture and [...] Read more.
In recent years, several steps forward have been made toward a more sustainable approach for the extraction of bioactive compounds from plant materials based on the application of green extraction principles. It is currently recognized that waste and by-products deriving from agriculture and food industries still contain a wide array of high value-added substances, which can be re-used to obtain new products with various applications in the food, supplement, pharmaceutical, and cosmetic industries. Anthocyanins are a class of these valuable metabolites; they confer the red, violet, and blue color to fruits and vegetables, and scientific evidence has accumulated over the last few decades to support their beneficial effects on human health, in great part deriving from their powerful antioxidant capacity. This review provides a general overview of the most recent green procedures that have been applied for the recovery of anthocyanins from plant-derived wastes and by-products. The most widely used green solvents and the main sustainable techniques utilized for recovering this class of flavonoids from various matrices are discussed, together with the variables that mainly impact the extraction yield. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
23 pages, 1401 KiB  
Review
Agri-Food Waste from Apple, Pear, and Sugar Beet as a Source of Protective Bioactive Molecules for Endothelial Dysfunction and Its Major Complications
by Cristiana Caliceti, Marco Malaguti, Luisa Marracino, Maria Cristina Barbalace, Paola Rizzo and Silvana Hrelia
Antioxidants 2022, 11(9), 1786; https://doi.org/10.3390/antiox11091786 - 10 Sep 2022
Cited by 14 | Viewed by 4015
Abstract
Endothelial damage is recognized as the initial step that precedes several cardiovascular diseases (CVD), such as atherosclerosis, hypertension, and coronary artery disease. It has been demonstrated that the best treatment for CVD is prevention, and, in the frame of a healthy lifestyle, the [...] Read more.
Endothelial damage is recognized as the initial step that precedes several cardiovascular diseases (CVD), such as atherosclerosis, hypertension, and coronary artery disease. It has been demonstrated that the best treatment for CVD is prevention, and, in the frame of a healthy lifestyle, the consumption of vegetables, rich in bioactive molecules, appears effective at reducing the risk of CVD. In this context, the large amount of agri-food industry waste, considered a global problem due to its environmental and economic impact, represents an unexplored source of bioactive compounds. This review provides a summary regarding the possible exploitation of waste or by-products derived by the processing of three traditional Italian crops—apple, pear, and sugar beet—as a source of bioactive molecules to protect endothelial function. Particular attention has been given to the bioactive chemical profile of these pomaces and their efficacy in various pathological conditions related to endothelial dysfunction. The waste matrices of apple, pear, and sugar beet crops can represent promising starting material for producing “upcycled” products with functional applications, such as the prevention of endothelial dysfunction linked to cardiovascular diseases. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Show Figures

Figure 1

12 pages, 305 KiB  
Review
Genotoxic Assessment of Nutraceuticals Obtained from Agricultural Biowaste: Where Do We “AMES”?
by Giorgia Musto, Valentina Laurenzi, Giuseppe Annunziata, Ettore Novellino and Mariano Stornaiuolo
Antioxidants 2022, 11(6), 1197; https://doi.org/10.3390/antiox11061197 - 18 Jun 2022
Cited by 6 | Viewed by 2366
Abstract
Several pharmaceutical companies are nowadays considering the use of agri-food waste as alternative raw material for the extraction of bioactive compounds to include in nutraceuticals and food supplements. This recycling activity is encountering the support of authorities, which are alarmed by air, soil [...] Read more.
Several pharmaceutical companies are nowadays considering the use of agri-food waste as alternative raw material for the extraction of bioactive compounds to include in nutraceuticals and food supplements. This recycling activity is encountering the support of authorities, which are alarmed by air, soil and water pollution generated by agricultural waste disposal. Waste reuse has several economic advantages: (i) its low cost; (ii) its abundance; (iii) the high content of bioactive molecule (antioxidants, minerals, fibers, fatty acids); as well as (iv) the financial support received by governments eager to promote eco-compatible and pollution-reducing practices. While nutraceuticals produced from biowaste are becoming popular, products that have been risk-assessed in terms of safety are quite rare. This despite waste biomass, in virtue of its chemical complexity, could, in many cases, mine the overall safety of the final nutraceutical product. In this review, we summarize the scientific results published on genotoxicity risk-assessment of bioactive compounds extracted from agricultural waste. The review depicts a scenario where the risk-assessment of biowaste derived products is still scarcely diffuse, but when available, it confirms the safety of these products, and lets us envisage their future inclusion in the list of botanicals allowed for formulation intended for human consumption. Full article
(This article belongs to the Special Issue Agri-Food Wastes as Natural Source of Bioactive Antioxidants)
Back to TopTop