Biological Potential of Antioxidant Compounds from Vegetable Sources

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

Deadline for manuscript submissions: closed (15 June 2023) | Viewed by 18699

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Department of Excellence of Pharmacy, University of Naples Federico II, Via D. Montesano, 49, 80131 Naples, Italy
Interests: organic chemistry; analytical chemistry; antivirals; nutraceuticals; food chemistry
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Department of Excellence of Pharmacy, University of Naples Federico II, Via D. Montesano, 49, 80131 Naples, Italy
Interests: cosmetics; transdermal absorption; nutricosmetics; skin analysis; analytical chemistry
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

In recent decades, it has been established that oxidative stress plays a pivotal role in the generation and progression of different pathological conditions, such as cardiovascular, diabetes, neurodegenerative diseases, and age-related disorders. Oxidative stress is defined as unbalance between reactive oxygen and nitrogen species (ROS/RNS) production and the physiological human antioxidant defense. In this context, great attention has been paid to natural antioxidant compounds as human health-protecting natural agents.

It is well known that fruits and vegetables are the richest sources of reducing molecules and the most studied are phenolic compounds, carotenoids, vitamins, triterpenic acids and some minerals (e.g., selenium and zinc). Different cellular molecular mechanisms have been proposed, not only limited to the evaluation of their radical scavenger and ferric reducing activities, but also their positive regulation of transcriptional factors involved in the induction of antioxidant endogenous enzymes expression.

In this Special Issue, we invite researchers to provide original research articles, clinical reports, and review articles related to every type of natural antioxidant. We are waiting for articles from researchers in a wide range of fields such as food chemistry, cosmetics, medicine, nutrition, and biochemistry. We want to make this Special Issue a valuable collection of new knowledge in this field.

Dr. Maria Maisto
Prof. Dr. Vincenzo Summa
Prof. Dr. Gian Carlo Tenore
Dr. Ritamaria Di Lorenzo
Guest Editors

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Keywords

  • reducing compounds
  • oxidative stress
  • natural sources
  • antioxidant activity
  • cellular damage

Published Papers (10 papers)

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Research

12 pages, 8398 KiB  
Article
Oil Extraction from Hemp Plant as a Potential Source of Cannabidiol for Healthy Protein Foods
by Olga Mileti, Noemi Baldino, Mario F. O. Paleologo, Francesca R. Lupi, Maria Marra, Domenico Iacopetta and Domenico Gabriele
Antioxidants 2023, 12(11), 1950; https://doi.org/10.3390/antiox12111950 - 01 Nov 2023
Viewed by 1525
Abstract
In recent years, the increasing demand for alternative foods has shifted research toward new sources enriched with nutraceutical molecules. It is well known that many diseases are caused by oxidative stress; thus, the supplementation of antioxidants has been proposed to reduce it. Cannabis [...] Read more.
In recent years, the increasing demand for alternative foods has shifted research toward new sources enriched with nutraceutical molecules. It is well known that many diseases are caused by oxidative stress; thus, the supplementation of antioxidants has been proposed to reduce it. Cannabis sativa L. is an interesting species that could provide an alternative source of antioxidants. This work aimed to investigate the possibility of optimizing the yield of cannabidiol (CBD) and recovering it from residual biomass (stalks), valorizing the residual biomass, and using this for protein bar preparation. Different extraction methods were used, and High-Pressure Liquid Chromatography (HPLC) analysis was used to analyze the extracts. Antioxidant power was investigated using the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. The best results in terms of CBD yield were obtained via dynamic maceration after decarboxylation with a quantity of 26.7 ± 2 mgCBD/graw material from inflorescences. The extract also shows good antioxidant power with an IC50 value of 38.1 ± 1.1 µg/mL measured using the DPPH assay. The CBD extract was added to the hemp oil to obtain dough for protein bars. The doughs were studied by taking rheological and technological measurements, and it was found that the protein bars could provide an excellent means for the consumption of products enriched with antioxidants because their CBD anti-inflammatory activity is preserved after cooking. Full article
(This article belongs to the Special Issue Biological Potential of Antioxidant Compounds from Vegetable Sources)
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14 pages, 443 KiB  
Article
Adherence to Mediterranean Diet: Any Association with NAFLD?
by Luigi Barrea, Ludovica Verde, Silvia Savastano, Annamaria Colao and Giovanna Muscogiuri
Antioxidants 2023, 12(7), 1318; https://doi.org/10.3390/antiox12071318 - 21 Jun 2023
Cited by 4 | Viewed by 1369
Abstract
Oxidative stress is considered one of the main determinants in the pathophysiology of non-alcoholic fatty liver disease (NAFLD) and obesity. The alterations of oxidant/antioxidant balance are related to chronic impairment of metabolism leading to mitochondrial dysfunction. Increased oxidative stress also triggers hepatocytes stress [...] Read more.
Oxidative stress is considered one of the main determinants in the pathophysiology of non-alcoholic fatty liver disease (NAFLD) and obesity. The alterations of oxidant/antioxidant balance are related to chronic impairment of metabolism leading to mitochondrial dysfunction. Increased oxidative stress also triggers hepatocytes stress pathways, leading to inflammation and contributing to the progression of non-alcoholic steatohepatitis (NASH). Currently, the first-line therapeutic treatment of NAFLD is based on lifestyle interventions, suggesting the Mediterranean Diet (MD) as a preferable nutritional approach due to its antioxidant properties. However, it is still debated if adherence to MD could have a role in determining the risk of developing NAFLD directly or indirectly through its effect on weight. We enrolled 336 subjects (aged 35.87 ± 10.37 years; BMI 31.18 ± 9.66 kg/m2) assessing anthropometric parameters, lifestyle habits, metabolic parameters (fasting plasma glucose, fasting plasma insulin, triglycerides (TG), total cholesterol, low-density (LDL) and high-density lipoprotein (HDL) cholesterol, alanine transaminase (ALT), aspartate aminotransferase (AST), and γ-glutamyltransferase (γGT), cardio-metabolic indices [Homeostatic Model Assessment Insulin Resistance (HoMA-IR), visceral adipose index (VAI) and fatty liver index (FLI)] and adherence to MD [with the PREvención con DIetaMEDiterránea (PREDIMED) questionnaire]. Subjects with NAFLD had significantly higher anthropometric parameters, cardio-metabolic indices and lower adherence to MD than subjects without NAFLD. In a multiple regression analysis, PREDIMED score was the main predictor of FLI (p < 0.001) and came in first, followed by HoMA-IR, while VAI was not a predictor. A PREDIMED score value of <6 could serve as a threshold to identify patients who are more likely to have NAFLD (p < 0.001). In conclusion, high adherence to MD resulted in a lower risk of having NAFLD. Adherence to MD could have a direct role on the risk of developing NAFLD, regardless of visceral adipose tissue. Full article
(This article belongs to the Special Issue Biological Potential of Antioxidant Compounds from Vegetable Sources)
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24 pages, 5852 KiB  
Article
Discrimination of Green Coffee (Coffea arabica and Coffea canephora) of Different Geographical Origin Based on Antioxidant Activity, High-Throughput Metabolomics, and DNA RFLP Fingerprinting
by Giuseppe Mannino, Ronja Kunz and Massimo E. Maffei
Antioxidants 2023, 12(5), 1135; https://doi.org/10.3390/antiox12051135 - 21 May 2023
Cited by 5 | Viewed by 2187
Abstract
The genus Coffea is known for the two species C. arabica (CA) and C. canephora (CC), which are used to prepare the beverage coffee. Proper identification of green beans of coffee varieties is based on phenotypic and phytochemical/molecular characteristics. In this work, a [...] Read more.
The genus Coffea is known for the two species C. arabica (CA) and C. canephora (CC), which are used to prepare the beverage coffee. Proper identification of green beans of coffee varieties is based on phenotypic and phytochemical/molecular characteristics. In this work, a combination of chemical (UV/Vis, HPLC-DAD–MS/MS, GC–MS, and GC-FID) and molecular (PCR-RFLP) fingerprinting was used to discriminate commercial green coffee accessions from different geographical origin. The highest content of polyphenols and flavonoids was always found in CC accessions, whereas CA showed lower values. ABTS and FRAP assays showed a significant correlation between phenolic content and antioxidant activity in most CC accessions. We identified 32 different compounds, including 28 flavonoids and four N-containing compounds. The highest contents of caffeine and melatonin were detected in CC accessions, whereas the highest levels of quercetin and kaempferol derivatives were found in CA accessions. Fatty acids of CC accessions were characterized by low levels of linoleic and cis octadecenoic acid and high amounts of elaidic acid and myristic acid. Discrimination of species according to their geographical origin was achieved using high-throughput data analysis, combining all measured parameters. Lastly, PCR-RFLP analysis was instrumental for the identification of recognition markers for the majority of accessions. Using the restriction enzyme AluI on the trnL-trnF region, we clearly discriminated C. canephora from C. arabica, whereas the cleavage performed by the restriction enzymes MseI and XholI on the 5S-rRNA-NTS region produced specific discrimination patterns useful for the correct identification of the different coffee accessions. This work extends our previous studies and provides new information on the complete flavonoid profile, combining high-throughput data with DNA fingerprinting to assess the geographical discrimination of green coffee. Full article
(This article belongs to the Special Issue Biological Potential of Antioxidant Compounds from Vegetable Sources)
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15 pages, 1337 KiB  
Article
Chemical Characterization and Antioxidant Activity of Nine Hypericum Species from Greece
by Eleni Kakouri, Panayiotis Trigas, Dimitra Daferera, Efstathia Skotti, Petros A. Tarantilis and Charalabos Kanakis
Antioxidants 2023, 12(4), 899; https://doi.org/10.3390/antiox12040899 - 08 Apr 2023
Cited by 2 | Viewed by 1435
Abstract
Hypericum L. comprises about 500 species distributed almost worldwide. Research has mainly focused on H. perforatum with confirmed biological activity on the alleviation of depression symptoms, among others. The compounds responsible for such activity are considered naphthodianthrones and acylphloroglucinols. Other Hypericum species are [...] Read more.
Hypericum L. comprises about 500 species distributed almost worldwide. Research has mainly focused on H. perforatum with confirmed biological activity on the alleviation of depression symptoms, among others. The compounds responsible for such activity are considered naphthodianthrones and acylphloroglucinols. Other Hypericum species are less studied or not studied, and further research is needed to complete the characterization of the genus. In this study we evaluated the qualitative and quantitative phytochemical profile of nine Hypericum species native to Greece, namely H. perforatum, H. tetrapterum, H. perfoliatum, H. rumeliacum subsp. apollinis, H. vesiculosum, H. cycladicum, H. fragile, H. olympicum and H. delphicum. Qualitative analysis was performed using the LC/Q-TOF/HRMS technique, while quantitative data were calculated with the single point external standard method. Additionally, we estimated the antioxidant activity of the extracts using DPPH and ABTS assays. Three species endemic to Greece (H. cycladicum, H. fragile, H. delphicum) were studied for the first time. Our results indicated that all studied species are rich in secondary metabolites, mainly of the flavonoids family, with strong antioxidant activity. Full article
(This article belongs to the Special Issue Biological Potential of Antioxidant Compounds from Vegetable Sources)
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18 pages, 2906 KiB  
Article
Impact of Elicitation on Plant Antioxidants Production in Taxus Cell Cultures
by Edgar Perez-Matas, Pascual Garcia-Perez, Mercedes Bonfill, Luigi Lucini, Diego Hidalgo-Martinez and Javier Palazon
Antioxidants 2023, 12(4), 887; https://doi.org/10.3390/antiox12040887 - 05 Apr 2023
Cited by 4 | Viewed by 1488
Abstract
Elicited cell cultures of Taxus spp. are successfully used as sustainable biotechnological production systems of the anticancer drug paclitaxel, but the effect of the induced metabolomic changes on the synthesis of other bioactive compounds by elicitation has been scarcely studied. In this work, [...] Read more.
Elicited cell cultures of Taxus spp. are successfully used as sustainable biotechnological production systems of the anticancer drug paclitaxel, but the effect of the induced metabolomic changes on the synthesis of other bioactive compounds by elicitation has been scarcely studied. In this work, a powerful combinatorial approach based on elicitation and untargeted metabolomics was applied to unravel and characterize the effects of the elicitors 1 µM of coronatine (COR) or 150 µM of salicylic acid (SA) on phenolic biosynthesis in Taxus baccata cell suspensions. Differential effects on cell growth and the phenylpropanoid biosynthetic pathway were observed. Untargeted metabolomics analysis revealed a total of 83 phenolic compounds, mainly flavonoids, phenolic acids, lignans, and stilbenes. The application of multivariate statistics identified the metabolite markers attributed to elicitation over time: up to 34 compounds at 8 days, 41 for 16 days, and 36 after 24 days of culture. The most notable metabolic changes in phenolic metabolism occurred after 8 days of COR and 16 days of SA elicitation. Besides demonstrating the significant and differential impact of elicitation treatments on the metabolic fingerprint of T. baccata cell suspensions, the results indicate that Taxus ssp. biofactories may potentially supply not only taxanes but also valuable phenolic antioxidants, in an efficient optimization of resources. Full article
(This article belongs to the Special Issue Biological Potential of Antioxidant Compounds from Vegetable Sources)
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15 pages, 1930 KiB  
Article
The Effect of Different Storage Conditions on Phytochemical Composition, Shelf-Life, and Bioactive Compounds of Voghiera Garlic PDO
by Paola Tedeschi, Federica Brugnoli, Stefania Merighi, Silvia Grassilli, Manuela Nigro, Martina Catani, Stefania Gessi, Valeria Bertagnolo, Alessia Travagli, Maria Fiorenza Caboni and Alberto Cavazzini
Antioxidants 2023, 12(2), 499; https://doi.org/10.3390/antiox12020499 - 16 Feb 2023
Cited by 3 | Viewed by 1831
Abstract
Voghiera garlic is an Italian white garlic variety which obtained in 2010 the Protected Designation of Origin. It is widely used for culinary purposes or as an ingredient for supplement production due to its phytochemical compositions. The storage conditions seem to be crucial [...] Read more.
Voghiera garlic is an Italian white garlic variety which obtained in 2010 the Protected Designation of Origin. It is widely used for culinary purposes or as an ingredient for supplement production due to its phytochemical compositions. The storage conditions seem to be crucial to retain the high quality of garlic bulbs and their by-products, taking into account the high importance of organosulfur and phenolic compounds for the bioactive potency of garlic and its shelf-life. This study aims to examine the effect of storage on the phytochemical composition, biological effects, and shelf-life of Voghiera garlic PDO. In detail, we considered (i) −4 °C (industrial storage) for 3, 6, and 9 months; (ii) +4 °C for 3 months (home conservation), and (iii) −4 °C for 3 months, plus +4 °C for another 3 months. We focused our attention on the organosulfur compounds, total condensed tannins, flavonoids, phenolic compounds, and related antioxidant activity changes during the storage period. To evaluate the bioactive effects, the Voghiera garlic extracts at different storage conditions were administered to a breast cancer cell line, while antioxidant and anti-inflammatory activity was detected using macrophage RAW 264.7 cells. We observed a decrease in sulfur compounds after 6 months which correlated to a decrease in bioactive effects, while the number of antioxidant compounds was stable during the storage period, showing the good effect of refrigerated temperature in maintaining garlic bulb shelf-life. Full article
(This article belongs to the Special Issue Biological Potential of Antioxidant Compounds from Vegetable Sources)
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15 pages, 893 KiB  
Article
Postharvest Treatment with Abscisic Acid Alleviates Chilling Injury in Zucchini Fruit by Regulating Phenolic Metabolism and Non-Enzymatic Antioxidant System
by Alejandro Castro-Cegrí, Sandra Sierra, Laura Hidalgo-Santiago, Adelaida Esteban-Muñoz, Manuel Jamilena, Dolores Garrido and Francisco Palma
Antioxidants 2023, 12(1), 211; https://doi.org/10.3390/antiox12010211 - 16 Jan 2023
Cited by 11 | Viewed by 3230
Abstract
Reports show that phytohormone abscisic acid (ABA) is involved in reducing zucchini postharvest chilling injury. During the storage of harvested fruit at low temperatures, chilling injury symptoms were associated with cell damage through the production of reactive oxygen species. In this work, we [...] Read more.
Reports show that phytohormone abscisic acid (ABA) is involved in reducing zucchini postharvest chilling injury. During the storage of harvested fruit at low temperatures, chilling injury symptoms were associated with cell damage through the production of reactive oxygen species. In this work, we have studied the importance of different non-enzymatic antioxidants on tolerance to cold stress in zucchini fruit treated with ABA. The application of ABA increases the antioxidant capacity of zucchini fruit during storage through the accumulation of ascorbate, carotenoids and polyphenolic compounds. The quantification of specific phenols was performed by UPLC/MS-MS, observing that exogenous ABA mainly activated the production of flavonoids. The rise in all these non-enzymatic antioxidants due to ABA correlates with a reduction in oxidative stress in treated fruit during cold stress. The results showed that the ABA mainly induces antioxidant metabolism during the first day of exposure to low temperatures, and this response is key to avoiding the occurrence of chilling injury. This work suggests an important protective role of non-enzymatic antioxidants and polyphenolic metabolism in the prevention of chilling injury in zucchini fruit. Full article
(This article belongs to the Special Issue Biological Potential of Antioxidant Compounds from Vegetable Sources)
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20 pages, 2597 KiB  
Article
Salinity Stress Ameliorates Pigments, Minerals, Polyphenolic Profiles, and Antiradical Capacity in Lalshak
by Umakanta Sarker, Md. Nazmul Hossain, Shinya Oba, Sezai Ercisli, Romina Alina Marc and Kirill S. Golokhvast
Antioxidants 2023, 12(1), 173; https://doi.org/10.3390/antiox12010173 - 11 Jan 2023
Cited by 23 | Viewed by 1654
Abstract
Previous studies have shown that salinity eustress enhances the nutritional and bioactive compounds and antiradical capacity (ARC) of vegetables and increases the food values for nourishing human diets. Amaranth is a salinity-resistant, rapidly grown C4 leafy vegetable with diverse variability and usage. [...] Read more.
Previous studies have shown that salinity eustress enhances the nutritional and bioactive compounds and antiradical capacity (ARC) of vegetables and increases the food values for nourishing human diets. Amaranth is a salinity-resistant, rapidly grown C4 leafy vegetable with diverse variability and usage. It has a high possibility to enhance nutritional and bioactive compounds and ARC by the application of salinity eustress. Hence, the present study aimed to evaluate the effects of sodium chloride stress response in a selected Lalshak (A. gangeticus) genotype on minerals, ascorbic acid (AsA), Folin–Ciocalteu reducing capacity, beta-carotene (BC), total flavonoids (TF), pigments, polyphenolic profiles, and ARC. A high-yield, high-ARC genotype (LS6) was grown under conditions of 0, 25, 50, and 100 mM sodium chloride in four replicates following a block design with complete randomization. We recognized nine copious polyphenolic compounds in this accession for the first time. Minerals, Folin–Ciocalteu reducing capacity, AsA, BC, pigments, polyphenolic profiles, and ARC of Lalshak were augmented progressively in the order: 0 < 25 < 50 < 100 mM sodium chloride. At 50 mM and 100 mM salt concentrations, minerals, AsA, Folin–Ciocalteu reducing capacity, BC, TF, pigments, polyphenolic profiles, and ARC of Lalshak were much greater than those of the control. Lalshak could be used as valuable food for human diets as a potent antioxidant. Sodium chloride-enriched Lalshak provided outstanding quality to the final product in terms of minerals, AsA, Folin–Ciocalteu reducing capacity, BC, TF, pigments, polyphenolic profiles, and ARC. We can cultivate it as a promising alternative crop in salinity-prone areas of the world. Full article
(This article belongs to the Special Issue Biological Potential of Antioxidant Compounds from Vegetable Sources)
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18 pages, 970 KiB  
Article
Tracking the Biostimulatory Effect of Fractions from a Commercial Plant Protein Hydrolysate in Greenhouse-Grown Lettuce
by Francesco Cristofano, Christophe El-Nakhel, Giuseppe Colla, Mariateresa Cardarelli, Youry Pii, Luigi Lucini and Youssef Rouphael
Antioxidants 2023, 12(1), 107; https://doi.org/10.3390/antiox12010107 - 31 Dec 2022
Cited by 5 | Viewed by 1542
Abstract
Protein hydrolysate biostimulants are environmentally friendly options for the reduction of nitrogen input, but their plant growth-promoting mechanisms are still not completely unveiled. Here, to put the “signaling peptide theory” to the test, a greenhouse experiment was undertaken using low (1 mM) and [...] Read more.
Protein hydrolysate biostimulants are environmentally friendly options for the reduction of nitrogen input, but their plant growth-promoting mechanisms are still not completely unveiled. Here, to put the “signaling peptide theory” to the test, a greenhouse experiment was undertaken using low (1 mM) and optimal (8 mM) NO3-treated butterhead lettuce and three molecular fractions (PH1 (>10 kDa), PH2 (1–10 kDa) and PH3 (<10 kDa) fractions), in addition to the whole product Vegamin®: PH, in a randomized block design. PH1 and PH3 significantly increased fresh yield (+8%) under optimal (lighter leaves), but not under low (darker leaves) NO3 conditions. Total ascorbic acid, lutein and β-carotene increased with PH3, and disinapoylgentobiose and kaempferol-3-hydroxyferuloyl-sophorosie-7-glucoside content increased with PH (whole/fractions) treatments, particularly under low NO3 conditions. The complete hydrolysate and analyzed peptide fractions have differential biostimulatory effects, enhancing the growth and nutritional quality of lettuce. Full article
(This article belongs to the Special Issue Biological Potential of Antioxidant Compounds from Vegetable Sources)
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24 pages, 4246 KiB  
Article
Blue Light Supplemented at Intervals in Long-Day Conditions Intervenes in Photoperiodic Flowering, Photosynthesis, and Antioxidant Properties in Chrysanthemums
by Jingli Yang, Jinnan Song and Byoung Ryong Jeong
Antioxidants 2022, 11(12), 2310; https://doi.org/10.3390/antiox11122310 - 22 Nov 2022
Cited by 1 | Viewed by 1222
Abstract
The flowering of chrysanthemum (Chrysanthemum morifolium Ramat.), inhibited by long-day lighting, can be reversed with a short period of low supplemental blue light (S-BL). Both flowering and the reactive oxygen species (ROS) scavenging processes are primarily driven by sugars created by photosynthetic [...] Read more.
The flowering of chrysanthemum (Chrysanthemum morifolium Ramat.), inhibited by long-day lighting, can be reversed with a short period of low supplemental blue light (S-BL). Both flowering and the reactive oxygen species (ROS) scavenging processes are primarily driven by sugars created by photosynthetic carbon assimilation. In addition, the antioxidant ability potentially affects flowering in photoperiod- and/or circadian rhythm-dependent manners. This indicates that there is an interactive relationship among blue (B) light, photosynthetic efficiency, sugar accumulation, and antioxidant ability in flowering regulation. Here, 4 h of 30 μmol·m−2·s−1 photosynthetic photon flux density (PPFD) S-BL was applied at the end of a 13-h long-day period (LD13 + 4B) at different intervals during 60 days of experimental duration. The five experimental groups were named according to the actual number of days of S-BL and their intervals: applied once every day, “60 days-(LD13 + 4B) (100.0%)”; once every other day, “30 days-(LD13 + 4B) (50.0%)”; once every three days, “15 days-(LD13 + 4B) (25.0%)”; once every five days, “10 days-(LD13 + 4B) (16.7%)”; and once every seven days, “7 days-(LD13 + 4B) (11.7%)”. Two non-S-BL control groups were also included: 60 10-h short days (60 days-SD10) and 13-h long days (60 days-LD13). At the harvest stage, varying degrees of flowering were observed except in “60 days-LD13” and “7 days-(LD13 + 4B) (11.7%)”. The number of flowers increased and the flower buds appeared earlier as the proportion of S-BL days increased in LD13 conditions, although the “60 days-SD10” gave the earliest flowering. The proportion of initial, pivotal, and optimal flowering was 16.7% (“10 days-(LD13 + 4B)”), 50.0% (“30 days-(LD13 + 4B)”), and 100.0% (“60 days-(LD13 + 4B)”), respectively. Meanwhile, a series of physiological parameters such as the production of enzymatic or non-enzymatic antioxidants, chlorophyll content, photosynthetic efficiency, enzyme activities, and carbohydrate accumulation were significantly improved by “30 days-(LD13 + 4B) (50.0%)” as a turning point until the peaks appeared in “60 days-(LD13 + 4B) (100.0%)”, as well as the expression of florigenic or anti-florigenic and some antioxidant-synthetic genes. Furthermore, the results of principal component analysis (PCA) indicated that S-BL days positively regulated flowering, photosynthesis, carbohydrate accumulation, and antioxidant production. In aggregate, the pivotal and optimal proportions of S-BL days to reconcile the relationship among flowering, photosynthetic carbon assimilation, and antioxidant ability were 50.0% and 100.0%, respectively. However, there are still significant gaps to be filled in order to determine the specific involvement of blue light and antioxidant abilities in flowering regulation. Full article
(This article belongs to the Special Issue Biological Potential of Antioxidant Compounds from Vegetable Sources)
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