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Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors

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

Deadline for manuscript submissions: closed (31 December 2020) | Viewed by 37288

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Special Issue Editors

Prof. Dr. María Serrano

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Department of Applied Biology, EPSO, University Miguel Hernández, 03312 Orihuela, Alicante, Spain
Interests: post-harvest; fruit quality; fruit ripening; ethylene; bioactive compounds; antioxidants; eco-friendly technologies; salicylates; polyamines; jasmonates; melatonin; γ-aminobutyric acid (GABA); cut flowers
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Prof. Dr. Daniel Valero

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Department of Food Technology, EPSO, CIAGRO-University Miguel Hernández, Ctra. Beniel km 3.2, 03312 Orihuela, Alicante, Spain
Interests: postharvest; elicitors; non-contaminant technologies; bioactive compounds; antioxidants; food technology
Special Issues, Collections and Topics in MDPI journals

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Dear Colleagues,

Oxidative stress has been linked to heart disease, cancer, arthritis, stroke, respiratory diseases, immune deficiency, and other inflammatory or ischemic conditions. Antioxidants prevent oxidation, and the free radical chain reaction is interrupted and damage to the cells is prevented. Although the principle is simple, however, the reality is far more complex. There are hundreds, possibly thousands of antioxidants. The role of diet is of great importance, with special focus on fruits and vegatebles. For that reason, consumers demand the intake of fruits and vegetables with excelent organoleptic quality but also with high contents of bioactive compounds (polyphenols, anthocyanins, carotenoids, and vitamins), which have antioxidant activity and are related to health-benefits.

This Special Issue will be focused on highlighting the effect of preharvest factors (cultivar, ripening stage at harvest, application of plant growth regulators, etc.) as well as postharvest factors (treatments, temperature, storage, chilling injury, etc.) on the change of these phytochemicals at harvest and during postharvest storage. Further, the latest knowledge about the use of noncontaminant and nontoxic natural compounds (considered as environmentally friendly) to perform new postharvest treatments that will maintain the quality and extend the shelf-life of fruits and vegetables without compromising their safety, appearance or sensory properties, and preserving the bioactive compounds and antioxidant activity will be also included. On the other hand, the effects of preharvest treatments with natural compounds on increasing the concentration of these biocompounds during the on-tree ripening process will be reported in order to increase the health beneficial effects of fruits and vegetable consumption.

Prof. Dr. María Serrano
Prof. Dr. Daniel Valero
Guest Editors

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Keywords

fruits
vegetables
antioxidants
phenolics
vitaminscarotanoids
storage
post-harvest treatments
pre-harvest treatments

Published Papers (11 papers)

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12 pages, 2556 KiB

Open AccessArticle

Preharvest Treatment with Oxalic Acid Improves Postharvest Storage of Lemon Fruit by Stimulation of the Antioxidant System and Phenolic Content

by Vicente Serna-Escolano, María José Giménez, Salvador Castillo, Juan Miguel Valverde, Domingo Martínez-Romero, Fabián Guillén, María Serrano, Daniel Valero and Pedro Javier Zapata

Antioxidants 2021, 10(6), 963; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10060963 - 15 Jun 2021

Cited by 18 | Viewed by 3166

Abstract

Lemon trees (Citrus limon (L.) Burm. F) were treated monthly with oxalic acid (OA) at 0.1, 0.5, and 1 mM from initial fruit growth on the tree until harvest in2019. The experiment was repeated in 2020, with the application of OA 1 mM (according to the best results of 2019). In both years, fruit from OA-treated trees and the controls were stored for 35 days at 10 °C. Results showed that all treatments reduced weight loss (WL) and maintained higher firmness, total soluble solids (TSS), and total acidity (TA) than in the controls. Meanwhile, colour (hue angle) did not show significant differences. The activity of antioxidant enzymes, catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD) in the flavedo of the fruit from the OA-treated trees was higher than in the controls at harvest and after 35 days of storage. Similarly, the total phenolic content (TPC) in the flavedo and juice of the fruit from the OA-treated trees were higher than in the controls. The increase in the activity of the antioxidant enzymes and TPC started with the first preharvest OA treatment and were maintained during fruit development on the tree until harvest. Preharvest OA treatments enhanced the antioxidant system of the lemon fruits, reducing the postharvest incidence of decay. Thus, OA could be a useful tool to increase the quality and functional properties of lemon fruits. Full article

(This article belongs to the Special Issue Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors)

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14 pages, 1144 KiB

Open AccessArticle

Melatonin Treatment to Pomegranate Trees Enhances Fruit Bioactive Compounds and Quality Traits at Harvest and during Postharvest Storage

by José M. Lorente-Mento, Fabián Guillén, Salvador Castillo, Domingo Martínez-Romero, Juan M. Valverde, Daniel Valero and María Serrano

Antioxidants 2021, 10(6), 820; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10060820 - 21 May 2021

Cited by 20 | Viewed by 2378

Abstract

The effect of melatonin pomegranate tree treatments on fruit quality and bioactive compounds with antioxidant activity at harvest and during storage at 10 °C for 60 days was assayed in two consecutive years, 2019 and 2020. In the first year, trees were treated with 0.1, 0.3 and 0.5 mM of melatonin along the developmental fruit growth cycle, and results showed that bioactive compounds (total phenolics and total and individual anthocyanins) and antioxidant activity at harvest were higher in fruits from melatonin-treated trees than in controls. Other fruit quality parameters, such as firmness, total soluble solids and aril red colour, were also increased as a consequence of melatonin treatment. In fruit from control tress, firmness and acidity levels decreased during storage, while increases occurred on total soluble solids, leading to fruit quality reductions. These changes were delayed, and even maintenance of total acidity was observed, in fruit from melatonin-treated trees with respect to controls, resulting in a fruit shelf-life increase. Moreover, concentration of phenolics and anthocyanins and antioxidant activity were maintained at higher levels in treated than in control fruits during the whole storage period. In general, all the mentioned effects were found at the highest level with the 0.1 mM melatonin dose, and then it was selected for repeating the experiment in the second year and results of the first year were confirmed. Thus, 0.1 mM melatonin treatment could be a useful tool to enhance aril content on bioactive compounds with antioxidant activity and health beneficial effects and to improve quality traits of pomegranate fruit, at harvest and during postharvest storage. Full article

(This article belongs to the Special Issue Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors)

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12 pages, 1555 KiB

Open AccessArticle

The Effect of Environmental pH during Trichothecium roseum (Pers.:Fr.) Link Inoculation of Apple Fruits on the Host Differential Reactive Oxygen Species Metabolism

by Zhanhong Han, Zhenyu Wang, Yang Bi, Yuanyuan Zong, Di Gong, Bin Wang, Baojun Li, Edward Sionov and Dov Prusky

Antioxidants 2021, 10(5), 692; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10050692 - 28 Apr 2021

Cited by 14 | Viewed by 1909

Abstract

Trichothecium roseum is an important postharvest pathogen, belonging to an alkalizing group of pathogens secreting ammonia during fungal growth and colonization of apple fruits. Fungal pH modulation is usually considered a factor for improving fungal gene expression, contributing to its pathogenicity. However, the effects of inoculation with T. roseum spore suspensions at increasing pH levels from pH 3 up to pH 7, on the reactive oxygen species (ROS) production and scavenging capability of the apple fruits, affecting host susceptibility, indicate that the pH regulation by the pathogens also affects host response and may contribute to colonization. The present results indicate that the inoculation of T. roseum spores at pH 3 caused the lowest cell membrane permeability, and reduced malondialdehyde content, NADPH oxidases activity, O₂^●− and H₂O₂ production in the colonized fruit. Observations of the colonized area on the 9th day after inoculation at pH 3, showed that the rate of O₂^●− production and H₂O₂ content was reduced by 57% and 25%, compared to their activities at pH 7. In contrast, antioxidative activities of superoxide dismutase, catalase and peroxidases of fruit tissue inoculated with spores’ suspension in the presence of a solution at pH 3.0 showed their highest activity. The catalase and peroxidases activities in the colonized tissue at pH 3 were higher by almost 58% and 55.9%, respectively, on the 6th day after inoculation compared to inoculation at pH 7. The activities of key enzymes of the ascorbate-glutathione (AsA-GSH) cycle and their substrates and products by the 9th day after fruit inoculation at pH 3 showed 150%, 31%, 16%, and 110% higher activities of ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase and glutathione reductase, respectively, compared to pH 7. A similar pattern of response was also observed in the accumulation of ascorbic acid and dehydroascorbate which showed a higher accumulation at pH 3 compared to the colonization at pH 7. The present results indicate that the metabolic regulation of the pH environment by the T. roseum not only modulates the fungal pathogenicity factors reported before, but it induces metabolic host changes contributing both together to fungal colonization. Full article

(This article belongs to the Special Issue Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors)

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19 pages, 5611 KiB

Open AccessArticle

Spicy Herb Extracts as a Potential Improver of the Antioxidant Properties and Inhibitor of Enzymatic Browning and Endogenous Microbiota Growth in Stored Mung Bean Sprouts

by Małgorzata Sikora, Urszula Złotek, Monika Kordowska-Wiater and Michał Świeca

Antioxidants 2021, 10(3), 425; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10030425 - 10 Mar 2021

Cited by 5 | Viewed by 2463

Abstract

The quality and shelf life of sprouts can be improved by postharvest application of water herb extracts. The effect of water infusions of marjoram, oregano, basil, and thyme on the phenolic content, antioxidant potential, and the microbiological and consumer quality of stored mung bean sprouts was studied. Compared to the control, the treatments increased total phenolic content. The highest amounts were determined in sprouts soaked in the thyme extract (6.8 mg/g d.m.). The infusions also inhibited the activity of enzymes utilizing phenolics, and marjoram and oregano were found to be the most effective. The increase in the level of phenolics was reflected in enhanced antioxidant properties (ability to quench cation radical ABTS^•+, reducing and chelating power). Both total phenolics and flavonoids, as well as antioxidant capacities, were highly bioaccessible in vitro. All the natural extracts effectively reduced the growth of total mesophilic bacteria, coliforms, and molds (they were more effective than ascorbic and kojic acids). The treatments did not exert a negative influence on the sensory properties or nutritional value of the sprouts, and even improved starch and protein digestibility. These results are very promising and may suggest a wider used of natural extracts as preservatives of minimally processed food. Full article

(This article belongs to the Special Issue Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors)

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11 pages, 6737 KiB

Open AccessFeature PaperArticle

Preharvest Methyl Jasmonate Treatment Increased the Antioxidant Activity and Glucosinolate Contents of Hydroponically Grown Pak Choi

by Min Woo Baek, Han Ryul Choi, Tifsehit Solomon, Cheon Soon Jeong, Ok-Hwan Lee and Shimeles Tilahun

Antioxidants 2021, 10(1), 131; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10010131 - 18 Jan 2021

Cited by 17 | Viewed by 3517

Abstract

Vertical hydroponics farming has emerged as an alternative solution to feed the continuously growing world population. Additionally, recent studies reported that the exogenous treatments of jasmonic acid influence the phytochemical composition of Brassicaceae. We conducted this study to determine the effect of preharvest methyl jasmonate (MeJA) treatment on the phytochemical composition and antioxidant activities of soil- and hydroponically grown pak choi. An aqueous solution of 0.5-mM MeJA was sprayed to saturation on the aerial plant part three days before harvest. The harvested pak choi was freeze-dried and then powdered to measure the antioxidant activity and the contents of chlorophylls (Chls), total phenolics and flavonoids, and glucosinolates (GSLs). The overall results revealed that pak choi grown in vertical hydroponics had higher total Chls and total phenolics than those grown in soil in the greenhouse, regardless of MeJA treatment. Nevertheless, the GSLs content and total flavonoids increased significantly due to MeJA treatment in both growing systems, and the highest values were recorded in hydroponically grown MeJA-treated pak choi. Similarly, the 2, 2-di-phenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, Trolox-equivalent antioxidant capacity (ABTS), oxygen radical absorbance capacity (ORAC), and ferric-reducing antioxidant power (FRAP) were highest in hydroponically grown MeJA-treated pak choi. Taken together, the preharvest foliar treatment of MeJA can be used to improve the phytochemical composition of pak choi grown in both growing systems. Interestingly, the results strongly support the use of MeJA treatment in the vertical hydroponics growing system compared to the conventional growing system in the soil. This indicates that supplementing the vertical hydroponic growing system with preharvest MeJA treatment could be the best option to improve both the yield per square meter and the quality of pak choi. Besides, MeJA-treated pak choi could be used as a value-added horticultural commodity, as its antioxidant activity increased after treatment. Moreover, after further studies, MeJA could also be applied to other Brassica vegetables to improve their GSL contents and antioxidant properties. Full article

(This article belongs to the Special Issue Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors)

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20 pages, 2119 KiB

Open AccessArticle

Mapping the Primary and Secondary Metabolomes of Carob (Ceratonia siliqua L.) Fruit and Its Postharvest Antioxidant Potential at Critical Stages of Ripening

by Marios C. Kyriacou, Chrystalla Antoniou, Youssef Rouphael, Giulia Graziani and Angelos Kyratzis

Antioxidants 2021, 10(1), 57; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10010057 - 05 Jan 2021

Cited by 28 | Viewed by 3211

Abstract

Six critical stages corresponding to major morphophysiological events in carob fruit ripening were defined, and changes in the primary and secondary metabolome and in vitro antioxidant capacity were examined in two genotypes collected at low (15 m) and high (510 m) altitudes from genetically identified and georeferenced trees. Soluble carbohydrates were analyzed by HPLC-RI, macro-minerals by ion chromatography coupled to conductivity detection and polyphenols by UHPLC-Q-Orbitrap-HRMS. spectroscopy facilitated assays for condensed tannins and in vitro free-radical scavenging capacity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP). The fruit respiration rate and moisture content declined sharply during the transition from the breaker to green pedicel stage. Sugar accumulation spiked at the onset of fruit coloration and culminated at 498.7 ± 8.4 mg g⁻¹ dry weight (dw) in the late ripe stage, while the ratio of reducing sugars to sucrose decreased from 3.45 ± 0.32 to 0.41 ± 0.02. The total phenolic compounds and condensed tannins declined with ripening, particularly during the transition from the breaker to green pedicel stage. Eighteen polyphenols were identified and quantitated, with catechins and hydrolyzable tannins being dominant until the onset of fruit coloration. The transition to the green pedicel stage signaled a precipitous decline (90.9%) in catechins, hydrolyzable tannins (60.2%) and flavonol glycosides (52.1%) concomitant to the rise in gallic acid, which was putatively fueled by the enzymatic hydrolysis of gallotannins in immature fruit. Catechins, hydrolyzable tannins and flavone glycosides were more abundant at higher altitudes and gallic acid at lower altitudes. An antioxidant capacity was also favored by higher elevations and declined with ripening, particularly after the breaker stage. Correlations with FRAP and DPPH assays were significant for the total phenolic content, condensed tannins, catechins and hydrolyzable tannins. The highest correlation factors were obtained for epigallocatechin-gallate (r = 0.920 and r = 0.900; p < 0.01). Although the sharp drop in hydrolyzable and nonhydrolyzable tannins and catechins compromised the in vitro antioxidant capacity at physiological maturity, it also reduced the astringency and configured a palatable organoleptic fruit profile. These changes unraveled significant episodes in the ripening-related secondary metabolism of the carob fruit. They further highlighted the value of immature carob as a potent source of gallotannins, with putative in vivo anti-inflammatory action, and of catechins beneficial in preventing and protecting against diseases caused by oxidative stress. Full article

(This article belongs to the Special Issue Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors)

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21 pages, 1622 KiB

Open AccessArticle

Carotenoids, Vitamin C, and Antioxidant Capacity in the Peel of Mandarin Fruit in Relation to the Susceptibility to Chilling Injury during Postharvest Cold Storage

by Florencia Rey, Lorenzo Zacarías and María J. Rodrigo

Antioxidants 2020, 9(12), 1296; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox9121296 - 17 Dec 2020

Cited by 34 | Viewed by 4851

Abstract

Chilling injury (CI) is a postharvest disorder occurring in the fruit of cold-sensitive Citrus species during storage at low temperatures. This study investigated the involvement of carotenoids and vitamin C, two major antioxidants of citrus peel, and the antioxidant capacity in the CI susceptibility of mandarin fruit. To that end, the fruit of three commercial varieties, Fortune, Nova, and Nadorcott, with significant differences in CI susceptibility, were selected. By on-tree fruit bagging, carotenoids and vitamin C contents were modified, and a differential effect of each cultivar on CI was observed. Carotenoid analysis in the peel revealed a strong negative correlation between total carotenoid concentration (TCC) at harvest, and specifically of β-cryptoxanthin and violaxanthin, and CI index at the end of storage. In contrast, vitamin C content was significantly and positively correlated with CI susceptibility. The antioxidant activity assessed by the DPPH• and FRAP reflected the contribution of vitamin C to the antioxidant system, while the SOAC assay correlated positively with TTC, β-cryptoxanthin, and violaxanthin. Collectively, the antioxidant capacity of carotenoids at harvest, as efficient singlet oxygen quenchers, suggests a protective role against the development of CI in mandarin fruit, while vitamin C is not likely playing a critical role. Full article

(This article belongs to the Special Issue Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors)

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15 pages, 1641 KiB

Open AccessArticle

Changes in Bioactive Compounds, Antioxidant Activity, and Nutritional Quality of Blood Orange Cultivars at Different Storage Temperatures

by Fariborz Habibi, Asghar Ramezanian, Fabián Guillén, Salvador Castillo, María Serrano and Daniel Valero

Antioxidants 2020, 9(10), 1016; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox9101016 - 20 Oct 2020

Cited by 41 | Viewed by 4320

Abstract

Information about the postharvest physiological behavior of blood orange cultivars can provide comprehensive insight into the best period of storage to maintain the highest fruit quality during prolonged cold storage. In this paper, changes in nutritional quality, bioactive compounds, and antioxidant enzymes in the juice of four blood orange cultivars (“Moro”, “Tarocco”, “Sanguinello”, and “Sanguine”) stored at 2 and 5 °C were studied. Parameters were measured after 0, 30, 60, 90, 120, 150, and 180 days, plus 2 days at 20 °C for shelf life. Sucrose was the sugar found in higher concentrations and decreased during storage in all cultivars, as did glucose and fructose. Organic acids decreased at both temperatures, with the highest content found in “Sanguinello”, especially major (citric acid) and ascorbic acid. Total phenolics content (TPC), total anthocyanins (TAC), and individual cyanidin 3-glucoside and cyanidin 3-(6″-malonylglucoside) increased for all cultivars, with “Sanguinello” having higher concentrations. The antioxidant enzymes catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) were also higher in “Sanguinello” and increased during storage. Overall, these results together with the sensory analysis suggested that “Sanguinello” would be the best cultivar for prolonged storage. The results of this study could be useful to select the best storage duration and temperature for each cultivar and provide the presence of such a high-value commodity for fresh consumption or juice processing long after the harvest season. Full article

(This article belongs to the Special Issue Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors)

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17 pages, 1446 KiB

Open AccessArticle

Preharvest Salicylate Treatments Enhance Antioxidant Compounds, Color and Crop Yield in Low Pigmented-Table Grape Cultivars and Preserve Quality Traits during Storage

by María E. García-Pastor, Pedro J. Zapata, Salvador Castillo, Domingo Martínez-Romero, Daniel Valero, María Serrano and Fabián Guillén

Antioxidants 2020, 9(9), 832; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox9090832 - 06 Sep 2020

Cited by 18 | Viewed by 3803

Abstract

Previous reports reported on the effectiveness of preharvest salicylic acid (SA) treatment on increasing fruit quality properties although no information is available about acetyl salicylic acid (ASA) and methyl salicylate (MeSa) treatments. Thus, SA, ASA and MeSa were applied at 1, 5, and 10 mM in 2016 and at 1, 0.1 and 0.01 mM in 2017 to vines of ‘Magenta’ and ‘Crimson’ table grapes. Preharvest salicylate treatments at high concentration, 5 and 10 mM, delayed berry ripening and reduced crop yield, while ripening was accelerated and yield increased at lower concentrations. In addition, SA, ASA, and MeSa treatments, at 1, 0.1, and 0.01 mM, improved berry color due to increased concentration of total and individual anthocyanins, for both cultivars. Quality parameters, and especially, antioxidant bioactive compounds, such as total phenolics and total and individual anthocyanins, were found at higher levels in treated berries at harvest and during prolonged cold storage, the highest effects being found in 0.1 mM MeSa treated table grapes. Overall, it could be concluded that MeSa treatment at 0.1 mM could be the most useful tool to increase bioactive compounds with antioxidant properties in table grape and in turn, their health beneficial properties, with additional effects on increasing crop yield, accelerating on-vine ripening process and maintaining quality traits during prolonged storage. Full article

(This article belongs to the Special Issue Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors)

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14 pages, 3082 KiB

Open AccessArticle

Detection of Antioxidant Phytochemicals Isolated from Camellia japonica Seeds Using HPLC and EPR Imaging

by Chalermpong Saenjum, Thanawat Pattananandecha and Kouichi Nakagawa

Antioxidants 2020, 9(6), 493; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox9060493 - 05 Jun 2020

Cited by 10 | Viewed by 2862

Abstract

In this study, we investigated the formation of stable radicals and compounds related to antioxidants in Camellia japonica seeds using high performance liquid chromatography (HPLC) and X-band electron paramagnetic resonance imaging (EPRI). The C. japonica seed coat extracts exhibited antioxidant activity in both in vitro and cell-based studies. The extracts inhibited reactive oxygen and reactive nitrogen species production in cell-based studies. HPLC chromatograms indicated that hydrophilic antioxidant compounds—namely, gallic acid, gallocatechin, epigallocatechin, caffeine, catechin, epicatechin, and epicatechin gallate—were found in the methanolic extract. Lipophilic antioxidant compounds—including α-tocopherol, γ-tocopherol, β-tocopherol, δ-tocopherol, α-tocotrienol, γ-tocotrienol, and δ-tocotrienol—were found in the hexane extract. EPRI primarily detected paramagnetic species in seed coats. These radical species were stable organic radicals based on the peak-to-peak line width and g-values. The signals from these stable radicals were strong and stable with a g-value of 2.002. Noninvasive EPRI of the radicals present in C. japonica seeds indicated that the stable radicals were essentially located in the seed coats. The EPRI of the cotyledon demonstrated that additional radicals were localized at an apex of the cotyledon. The results indicated that the stable radicals detected by EPRI and the hydrophilic and lipophilic antioxidant compounds analyzed by HPLC were related to antioxidant reactants and products. Full article

(This article belongs to the Special Issue Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors)

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30 pages, 527 KiB

Open AccessReview

Genetic and Pre- and Postharvest Factors Influencing the Content of Antioxidants in Cucurbit Crops

by Cecilia Martínez, Juan Luis Valenzuela and Manuel Jamilena

Antioxidants 2021, 10(6), 894; https://0-doi-org.brum.beds.ac.uk/10.3390/antiox10060894 - 02 Jun 2021

Cited by 6 | Viewed by 3464

Abstract

Cucurbitaceae is one of the most economically important plant families, and includes some worldwide cultivated species like cucumber, melons, and squashes, and some regionally cultivated and feral species that contribute to the human diet. For centuries, cucurbits have been appreciated because of their nutritional value and, in traditional medicine, because of their ability to alleviate certain ailments. Several studies have demonstrated the remarkable contents of valuable compounds in cucurbits, including antioxidants such as polyphenols, flavonoids, and carotenoids, but also tannins and terpenoids, which are abundant. This antioxidant power is beneficial for human health, but also in facing plant diseases and abiotic stresses. This review brings together data on the antioxidant properties of cucurbit species, addressing the genetic and pre- and postharvest factors that regulate the antioxidant content in different plant organs. Environmental conditions, management, storage, and pre- and postharvest treatments influencing the biosynthesis and activity of antioxidants, together with the biodiversity of this family, are determinant in improving the antioxidant potential of this group of species. Plant breeding, as well as the development of innovative biotechnological approaches, is also leading to new possibilities for exploiting cucurbits as functional products. Full article

(This article belongs to the Special Issue Antioxidant Systems in Fruits and Vegetables: Pre- and Postharvest Factors)

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