Phytochemical Antioxidants and Health

A special issue of Antioxidants (ISSN 2076-3921). This special issue belongs to the section "Health Outcomes of Antioxidants and Oxidative Stress".

Deadline for manuscript submissions: closed (30 September 2019) | Viewed by 168279

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Food Science and Technology Program, Department of Life Sciences, Beijing Normal University-Hong Kong Baptist University United International College, Zhuhai 519087, China
Interests: phytochemicals; natural products; functional foods; human health
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Dear Colleagues,

It is widely accepted that free-radical-induced oxidative damage is involved with various human diseases, such as cardiovascular diseases, neural disorders, such as Alzheimer’s and Parkinson’s disease, diabetes, obesity, and various cancers. Antioxidants are substances that delay or inhibit oxidative damage when present in small quantities compared to an oxidizable substrate. Therefore, antioxidants can help in disease prevention by effectively quenching free radicals or inhibiting damage caused by them. It is recognized that the health effects of natural products including food and herbal medicines are generally associated with antioxidative activities or free radical scavenging properties of phytochemicals.

We invite you to contribute your latest research findings or a review article to this Special Issue, which will bring together current research concerning and critical thinking on phytochemical antioxidants, and the role that antioxidants can play in reducing oxidative stress in various disease statuses. Your contribution can include either in vitro or in vivo studies relating to any of the following topics: Antioxidative activities of phytochemicals; molecular mechanisms of phytochemical antioxidants in disease prevention; and the role of phytochemicals or antioxidants in signaling, cell metabolism, cell cycle, cellular stress, and chronic diseases.

We look forward to your contribution.

Prof. Baojun Xu
Guest Editor

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Keywords

  • Antioxidants
  • Oxidative stress
  • Free radical scavenging
  • Phytochemicals
  • Molecular mechanisms
  • Health promotion
  • Disease prevention

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Published Papers (23 papers)

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19 pages, 3800 KiB  
Article
Comparative Study on Phytochemical Profiles and Antioxidant Capacities of Chestnuts Produced in Different Geographic Area in China
by Ziyun Xu, Maninder Meenu, Pengyu Chen and Baojun Xu
Antioxidants 2020, 9(3), 190; https://doi.org/10.3390/antiox9030190 - 25 Feb 2020
Cited by 30 | Viewed by 3424
Abstract
This study aimed to systematically assess the phenolic profiles and antioxidant capacities of 21 chestnut samples collected from six geographical areas of China. All these samples exhibit significant differences (p < 0.05) in total phenolic contents (TPC), total flavonoids content (TFC), condensed [...] Read more.
This study aimed to systematically assess the phenolic profiles and antioxidant capacities of 21 chestnut samples collected from six geographical areas of China. All these samples exhibit significant differences (p < 0.05) in total phenolic contents (TPC), total flavonoids content (TFC), condensed tannin content (CTC) and antioxidant capacities assessed by DPPH free radical scavenging capacity (DPPH), ABTS free radical scavenging capacities (ABTS), ferric reducing antioxidant power (FRAP), and 14 free phenolic acids. Chestnuts collected from Fuzhou, Jiangxi (East China) exhibited the maximum values for TPC (2.35 mg GAE/g), CTC (13.52 mg CAE/g), DPPH (16.74 μmol TE/g), ABTS (24.83 μmol TE/g), FRAP assays (3.20 mmol FE/100 g), and total free phenolic acids (314.87 µg/g). Vanillin and gallic acids were found to be the most abundant free phenolic compounds among other 14 phenolic compounds detected by HPLC. Overall, the samples from South China revealed maximum mean values for TPC, CTC, DPPH, and ABTS assays. Among the three chestnut varieties, Banli presented prominent mean values for all the assays. These finding will be beneficial for production of novel functional food and developing high-quality chestnut varieties. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
25 pages, 1736 KiB  
Article
The Health-Promoting Potential of Salix spp. Bark Polar Extracts: Key Insights on Phenolic Composition and In Vitro Bioactivity and Biocompatibility
by Patrícia A. B. Ramos, Catarina Moreirinha, Sara Silva, Eduardo M. Costa, Mariana Veiga, Ezequiel Coscueta, Sónia A. O. Santos, Adelaide Almeida, M. Manuela Pintado, Carmen S. R. Freire, Artur M. S. Silva and Armando J. D. Silvestre
Antioxidants 2019, 8(12), 609; https://doi.org/10.3390/antiox8120609 - 30 Nov 2019
Cited by 27 | Viewed by 4806
Abstract
Salix spp. have been exploited for energy generation, along with folk medicine use of bark extracts for antipyretic and analgesic benefits. Bark phenolic components, rather than salicin, have demonstrated interesting bioactivities, which may ensure the sustainable bioprospection of Salix bark. Therefore, this study [...] Read more.
Salix spp. have been exploited for energy generation, along with folk medicine use of bark extracts for antipyretic and analgesic benefits. Bark phenolic components, rather than salicin, have demonstrated interesting bioactivities, which may ensure the sustainable bioprospection of Salix bark. Therefore, this study highlights the detailed phenolic characterization, as well as the in vitro antioxidant, anti-hypertensive, Staphylococcus aureus growth inhibitory effects, and biocompatibility of Salix atrocinerea Brot., Salix fragilis L., and Salix viminalis L. bark polar extracts. Fifteen phenolic compounds were characterized by ultra-high-performance liquid chromatography-ultraviolet detection-mass spectrometry analysis, from which two flavan-3-ols, an acetophenone, five flavanones, and a flavonol were detected, for the first time, as their bark components. Salix bark extracts demonstrated strong free radical scavenging activity (5.58–23.62 µg mL−1 IC50 range), effective inhibition on angiotensin-I converting enzyme (58–84%), and S. aureus bactericidal action at 1250–2500 µg mL−1 (6–8 log CFU mL−1 reduction range). All tested Salix bark extracts did not show cytotoxic potential against Caco-2 cells, as well as S. atrocinerea Brot. and S. fragilis L. extracts at 625 and 1250 µg mL−1 against HaCaT and L929 cells. These valuable findings can pave innovative and safer food, nutraceutical, and/or cosmetic applications of Salix bark phenolic-containing fractions. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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14 pages, 3516 KiB  
Article
Effects of Lespedeza Bicolor Extract on Regulation of AMPK Associated Hepatic Lipid Metabolism in Type 2 Diabetic Mice
by Younmi Kim, Heaji Lee, Sun Yeou Kim and Yunsook Lim
Antioxidants 2019, 8(12), 599; https://doi.org/10.3390/antiox8120599 - 29 Nov 2019
Cited by 18 | Viewed by 3237
Abstract
Lespedeza bicolor (LB) is one of the ornamental plants used for the treatment of inflammation caused by oxidative damage. However, its beneficial effects on hyperglycemia-induced hepatic damage and the related molecular mechanisms remain unclear. We hypothesized that Lespedeza bicolor extract (LBE) would attenuate [...] Read more.
Lespedeza bicolor (LB) is one of the ornamental plants used for the treatment of inflammation caused by oxidative damage. However, its beneficial effects on hyperglycemia-induced hepatic damage and the related molecular mechanisms remain unclear. We hypothesized that Lespedeza bicolor extract (LBE) would attenuate hyperglycemia-induced liver injury in type 2 diabetes mellitus (T2DM). Diabetes was induced by a low dosage of streptozotocin (STZ) injection (30 mg/kg) with a high fat diet in male C57BL/6J mice. LBE was administered orally at 100 mg/kg or 250 mg/kg for 12 weeks. LBE supplementation regardless of dosage ameliorated plasma levels of hemoglobin A1c (HbA1c) in diabetic mice. Moreover, both LBE supplementations upregulated AMP-activation kinase (AMPK), which may activate sirtuin1 (SIRT) associated pathway accompanied by decreased lipid synthesis at low dose of LBE supplementation. These changes were in part explained by reduced protein levels of oxidative stress (nuclear factor erythroid 2-related factor 2 (Nrf2) and catalase), inflammation (nuclear factor kappa B (NF-κB), interleukin-1β (IL-1β), interleukin-6 (IL-6), and nitric oxide synthases (iNOS)), and fibrosis (α-smooth muscle actin (α-SMA) and protein kinase C (PKC)) in diabetic liver. Taken together, LBE might be a potential nutraceutical to ameliorate hepatic damage by regulation of AMPK associated pathway via oxidative stress, inflammation, and fibrosis in T2DM. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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12 pages, 2363 KiB  
Article
Functional Analysis of Macromolecular Polysaccharides: Whitening, Moisturizing, Anti-Oxidant, and Cell Proliferation
by Chien-Jen Kao, Hsin-Yu Chou, Yu-Chen Lin, Qinghong Liu and Hui-Min David Wang
Antioxidants 2019, 8(11), 533; https://doi.org/10.3390/antiox8110533 - 7 Nov 2019
Cited by 19 | Viewed by 4287
Abstract
In this research we utilized extracts from two different nature products, Achatina fulica and Heimiella retispora, to enhance skin moisturizing abilities, anti-oxidative properties, and cell proliferations. It was observed that two polysaccharides with anti-oxidative effects by chelating metal ions reduced oxidative stress [...] Read more.
In this research we utilized extracts from two different nature products, Achatina fulica and Heimiella retispora, to enhance skin moisturizing abilities, anti-oxidative properties, and cell proliferations. It was observed that two polysaccharides with anti-oxidative effects by chelating metal ions reduced oxidative stress and further blocked the formation of reactive oxygen species syntheses. To detect whether there was a similar effect within the cellular mechanism, a flow cytometry was applied for sensing the oxidative level and it was found that both materials inhibited the endogenous oxidative stress, which was induced by phorbol-12-myristate-13-acetate (PMA). Both polysaccharides also stimulated the production of collagen to maintain skin tightness and a moisturizing effect. In summary, we developed two macromolecular polysaccharides with potential applications in dermal care. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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15 pages, 3962 KiB  
Article
Maltol Improves APAP-Induced Hepatotoxicity by Inhibiting Oxidative Stress and Inflammation Response via NF-κB and PI3K/Akt Signal Pathways
by Zi Wang, Weinan Hao, Junnan Hu, Xiaojie Mi, Ye Han, Shen Ren, Shuang Jiang, Yingping Wang, Xindian Li and Wei Li
Antioxidants 2019, 8(9), 395; https://doi.org/10.3390/antiox8090395 - 12 Sep 2019
Cited by 63 | Viewed by 5040
Abstract
Maltol, a food-flavoring agent and Maillard reaction product formed during the processing of red ginseng (Panax ginseng, C.A. Meyer), has been confirmed to exert a hepatoprotective effect in alcohol-induced oxidative damage in mice. However, its beneficial effects on acetaminophen (APAP)-induced hepatotoxicity [...] Read more.
Maltol, a food-flavoring agent and Maillard reaction product formed during the processing of red ginseng (Panax ginseng, C.A. Meyer), has been confirmed to exert a hepatoprotective effect in alcohol-induced oxidative damage in mice. However, its beneficial effects on acetaminophen (APAP)-induced hepatotoxicity and the related molecular mechanisms remain unclear. The purpose of this article was to investigate the protective effect and elucidate the mechanisms of action of maltol on APAP-induced liver injury in vivo. Maltol was administered orally at 50 and 100 mg/kg daily for seven consecutive days, then a single intraperitoneal injection of APAP (250 mg/kg) was performed after the final maltol administration. Liver function, oxidative indices, inflammatory factors—including serum alanine and aspartate aminotransferases (ALT and AST), tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), liver glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), cytochrome P450 E1 (CYP2E1) and 4-hydroxynonenal (4-HNE) were measured. Results demonstrated that maltol possessed a protective effect on APAP-induced liver injury. Liver histological changes and Hoechst 33258 staining also provided strong evidence for the protective effect of maltol. Furthermore, a maltol supplement mitigated APAP-induced inflammatory responses by increasing phosphorylated nuclear factor-kappa B (NF-κB), inhibitor kappa B kinase α/β (IKKα/β), and NF-kappa-B inhibitor alpha (IκBα) in NF-κB signal pathways. Immunoblotting results showed that maltol pretreatment downregulated the protein expression levels of the B-cell-lymphoma-2 (Bcl-2) family and caspase and altered the phosphorylation of phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) in a dose-dependent manner. In conclusion, our findings clearly demonstrate that maltol exerts a significant liver protection effect, which may partly be ascribed to its anti-inflammatory and anti-apoptotic action via regulation of the PI3K/Akt signaling pathway. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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16 pages, 3508 KiB  
Article
Sulfuric Odor Precursor S-Allyl-l-Cysteine Sulfoxide in Garlic Induces Detoxifying Enzymes and Prevents Hepatic Injury
by Yusuke Yamaguchi, Ryosuke Honma, Tomoaki Yazaki, Takeshi Shibuya, Tomoya Sakaguchi, Harumi Uto-Kondo and Hitomi Kumagai
Antioxidants 2019, 8(9), 385; https://doi.org/10.3390/antiox8090385 - 10 Sep 2019
Cited by 24 | Viewed by 4999
Abstract
S-Allyl-l-cysteine sulfoxide (ACSO) is a precursor of garlic-odor compounds like diallyl disulfide (DADS) and diallyl trisulfide (DATS) known as bioactive components. ACSO has suitable properties as a food material because it is water-soluble, odorless, tasteless and rich in bulbs of [...] Read more.
S-Allyl-l-cysteine sulfoxide (ACSO) is a precursor of garlic-odor compounds like diallyl disulfide (DADS) and diallyl trisulfide (DATS) known as bioactive components. ACSO has suitable properties as a food material because it is water-soluble, odorless, tasteless and rich in bulbs of fresh garlic. The present study was conducted to examine the preventive effect of ACSO on hepatic injury induced by CCl4 in rats. ACSO, its analogs and garlic-odor compounds were each orally administered via gavage for five consecutive days before inducing hepatic injury. Then, biomarkers for hepatic injury and antioxidative state were measured. Furthermore, we evaluated the absorption and metabolism of ACSO in the small intestine of rats and NF-E2-related factor 2 (Nrf2) nuclear translocation by ACSO using HepG2 cells. As a result, ACSO, DADS and DATS significantly suppressed the increases in biomarkers for hepatic injury such as the activities of aspartate transaminase (AST), alanine transaminase (ALT) and lactate dehydrogenase (LDH), and decreases in antioxidative potency such as glutathione (GSH) level and the activities of glutathione S-transferase (GST) and glutathione peroxidase (GPx). We also found ACSO was absorbed into the portal vein from the small intestine but partially metabolized to DADS probably in the small intestine. In in vitro study, ACSO induced Nrf2 nuclear translocation in HepG2 cells, which is recognized as an initial trigger to induce antioxidative and detoxifying enzymes. Taken together, orally administered ACSO probably reached the liver and induced antioxidative and detoxifying enzymes by Nrf2 nuclear translocation, resulting in prevention of hepatic injury. DADS produced by the metabolism of ACSO in the small intestine might also have contributed to the prevention of hepatic injury. These results suggest potential use of ACSO in functional foods that prevent hepatic injury and other diseases caused by reactive oxygen species (ROS). Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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23 pages, 14156 KiB  
Article
Polydatin Encapsulated Poly [Lactic-co-glycolic acid] Nanoformulation Counteract the 7,12-Dimethylbenz[a] Anthracene Mediated Experimental Carcinogenesis through the Inhibition of Cell Proliferation
by Sankaran Vijayalakshmi, Arokia Vijaya Anand Mariadoss, Vinayagam Ramachandran, Vijayakumar Shalini, Balupillai Agilan, Casimeer C. Sangeetha, Periyasamy Balu, Venkata Subbaih Kotakadi, Venkatachalam Karthikkumar and David Ernest
Antioxidants 2019, 8(9), 375; https://doi.org/10.3390/antiox8090375 - 5 Sep 2019
Cited by 24 | Viewed by 4226
Abstract
In the present study, the authors have attempted to fabricate Polydatin encapsulated Poly [lactic-co-glycolic acid] (POL-PLGA-NPs) to counteract 7,12-dimethyl benzyl anthracene (DMBA) promoted buccal pouch carcinogenesis in experimental animals. The bio-formulated POL-PLGA-NPs were characterized by dynamic light scattering (DLS), Fourier transform infrared (FTIR) [...] Read more.
In the present study, the authors have attempted to fabricate Polydatin encapsulated Poly [lactic-co-glycolic acid] (POL-PLGA-NPs) to counteract 7,12-dimethyl benzyl anthracene (DMBA) promoted buccal pouch carcinogenesis in experimental animals. The bio-formulated POL-PLGA-NPs were characterized by dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD) pattern analysis, and transmission electron microscope (TEM). In addition, the nano-chemopreventive potential of POL-PLGA-NPs was assessed by scrutinizing the neoplastic incidence and analyzing the status of lipid peroxidation, antioxidants, phase I, phase II detoxification status, and histopathological changes and in DMBA-treated animals. In golden Syrian hamsters, oral squamous cell carcinoma (OSCC) was generated by painting with 0.5% DMBA in liquid paraffin three times a week for 14 weeks. After 100% tumor formation was observed, high tumor volume, tumor burden, and altered levels of biochemical status were observed in the DMBA-painted hamsters. Intra-gastric administration of varying concentration of POL-PLGA-NPs (7.5, 15, and 30 mg/kg b.wt) to DMBA-treated hamsters assumedly prevents oncological incidences and restores the status of the biochemical markers. It also significantly enhances the apoptotic associated and inhibits the cancer cell proliferative markers expression (p53, Bax, Bcl-2, cleaved caspase 3, cyclin-D1). The present study reveals that POL-PLGA-NPs is a penitential candidate for nano-chemopreventive, anti-lipid peroxidative, and antioxidant potential, and also has a modulating effect on the phase I and Phase II detoxification system, which is associated with reduced cell proliferation and induced apoptosis in experimental oral carcinogenesis. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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18 pages, 4930 KiB  
Article
Supplementation of Saponins from Leaves of Panax quinquefolius Mitigates Cisplatin-Evoked Cardiotoxicity via Inhibiting Oxidative Stress-Associated Inflammation and Apoptosis in Mice
by Jing-Jing Xing, Jin-Gang Hou, Ying Liu, Ruo-Bing Zhang, Shuang Jiang, Shen Ren, Ying-Ping Wang, Qiong Shen, Wei Li, Xin-Dian Li and Zi Wang
Antioxidants 2019, 8(9), 347; https://doi.org/10.3390/antiox8090347 - 1 Sep 2019
Cited by 45 | Viewed by 4896
Abstract
Background: Although kidney injury caused by cisplatin has attracted much attention, cisplatin-induced cardiotoxicity is elusive. Our previous studies have confirmed that saponins (ginsenosides) from Panax quinquefolius can effectively reduce acute renal injuries. Our current study aimed to identify the potential effects of saponins [...] Read more.
Background: Although kidney injury caused by cisplatin has attracted much attention, cisplatin-induced cardiotoxicity is elusive. Our previous studies have confirmed that saponins (ginsenosides) from Panax quinquefolius can effectively reduce acute renal injuries. Our current study aimed to identify the potential effects of saponins from leaves of P. quinquefolius (PQS) on cisplatin-evoked cardiotoxicity. Methods: Mice were intragastrically with PQS at the doses of 125 and 250 mg/kg daily for 15 days. The mice in cisplatin group and PQS + cisplatin groups received four times intraperitoneal injections of cisplatin (3 mg/kg) two days at a time from the 7th day, respectively. All mice were killed at 48 h following final cisplatin injection. Body weights, blood and organic samples were collected immediately. Results: Our results showed that cisplatin-challenged mice experienced a remarkable cardiac damage with obvious histopathological changes and elevation of lactate dehydrogenase (LDH), creatine kinase (CK), creatine kinase isoenzyme MB (CK-MB) and cardiac troponin T (cTnT) concentrations and viabilities in serum. Cisplatin also impaired antioxidative defense system in heart tissues manifested by a remarkable reduction in reduced glutathione (GSH) content and superoxide dismutase (SOD) activity, demonstrating the overproduction of reactive oxygen species (ROS) and oxidative stress. Interestingly, PQS (125 and 250 mg/kg) can attenuate cisplatin-evoked changes in the above-mentioned parameters. Additionally, PQS administration significantly alleviated the oxidation resulted from inflammatory responses and apoptosis in cardiac tissues via inhibition of overexpressions of TNF-α, IL-1β, Bax, and Bad as well as the caspase family members like caspase-3, and 8, respectively. Conclusion: Findings from our present research clearly indicated that PQS exerted significant effects on cisplatin-induced cardiotoxicity in part by inhibition of the NF-κB activity and regulation of PI3K/Akt/apoptosis mediated signaling pathways. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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28 pages, 2786 KiB  
Article
Qualitative Chemical Characterization and Multidirectional Biological Investigation of Leaves and Bark Extracts of Anogeissus leiocarpus (DC.) Guill. & Perr. (Combretaceae)
by Giustino Orlando, Claudio Ferrante, Gokhan Zengin, Kouadio Ibrahime Sinan, Kouadio Bene, Alina Diuzheva, József Jekő, Zoltán Cziáky, Simonetta Di Simone, Lucia Recinella, Annalisa Chiavaroli, Sheila Leone, Luigi Brunetti, Carene Marie Nancy Picot-Allain, Mohamad Fawzi Mahomoodally and Luigi Menghini
Antioxidants 2019, 8(9), 343; https://doi.org/10.3390/antiox8090343 - 1 Sep 2019
Cited by 16 | Viewed by 4460
Abstract
Anogeissus leiocarpus (DC.) Guill. & Perr. (Combretaceae) has a long history of use by folk populations for the management of multiple human ailments. Based on the published literature, there has been no attempt to conduct a comparative assessment of the biological activity and [...] Read more.
Anogeissus leiocarpus (DC.) Guill. & Perr. (Combretaceae) has a long history of use by folk populations for the management of multiple human ailments. Based on the published literature, there has been no attempt to conduct a comparative assessment of the biological activity and the phytochemical profiles of the leaves and stem bark of A. leiocarpus extracted using methanol, ethyl acetate, and water. By high-performance liquid chromatography with electrospray ionization mass spectrometric detection (HPLC-ESI-MSn) analysis, quinic, shikimic, gallic, and protocatechuic acids were tentatively identified from all the extracts, while chlorogenic, caffeic, ferulic, and dodecanedioic acids were only characterised from the leaves extracts. Additionally, a pharmacological study was carried out to evaluate potential protective effects that are induced by the extracts in rat colon and colon cancer HCT116 cell line. In general, the methanol and water extracts of A. leiocarpus leaves and stem bark showed potent radical scavenging and reducing properties. It was noted that the stem bark extracts were more potent antioxidants as compared to the leaves extracts. The methanol extract of A. leiocarpus leaves showed the highest acetyl (4.68 mg galantamine equivalent/g) and butyryl (4.0 mg galantamine equivalent/g) cholinesterase inhibition. Among ethyl acetate extracts, the pharmacological investigation suggested stem bark ethyl acetate extracts to be the most promising. This extract revealed ability to protect rat colon from lipopolysaccharide-induced oxidative stress, without exerting promoting effects on HCT116 cell line viability and migration. As a conclusion, A. leiocarpus represents a potential source of bioactive compounds in the development of novel therapeutic agents. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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12 pages, 618 KiB  
Article
Increase of 4-Hydroxybenzoic, a Bioactive Phenolic Compound, after an Organic Intervention Diet
by Sara Hurtado-Barroso, Paola Quifer-Rada, María Marhuenda-Muñoz, Jose Fernando Rinaldi de Alvarenga, Anna Tresserra-Rimbau and Rosa M. Lamuela-Raventós
Antioxidants 2019, 8(9), 340; https://doi.org/10.3390/antiox8090340 - 24 Aug 2019
Cited by 7 | Viewed by 3377
Abstract
Consumption of organic products is increasing yearly due to perceived health-promoting qualities. Several studies have shown higher amounts of phytochemicals such as polyphenols and carotenoids in foods produced by this type of agriculture than in conventional foods, but whether this increase has an [...] Read more.
Consumption of organic products is increasing yearly due to perceived health-promoting qualities. Several studies have shown higher amounts of phytochemicals such as polyphenols and carotenoids in foods produced by this type of agriculture than in conventional foods, but whether this increase has an impact on humans still needs to be assessed. A randomized, controlled and crossover study was carried out in nineteen healthy subjects aged 18–40 years, who all followed an organic and conventional healthy diet, both for a 4-week period. Analysis of biological samples revealed a significant increase on the excretion of 4-hydroxybenzoic acid (4-HBA), a phenolic metabolite with biological activity, after the organic intervention. However, no changes were observed in the other variables analyzed. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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15 pages, 3668 KiB  
Article
Application of Natural Flavonoids to Impart Antioxidant and Antibacterial Activities to Polyamide Fiber for Health Care Applications
by Ya-Dong Li, Jin-Ping Guan, Ren-Cheng Tang and Yi-Fan Qiao
Antioxidants 2019, 8(8), 301; https://doi.org/10.3390/antiox8080301 - 12 Aug 2019
Cited by 37 | Viewed by 6163
Abstract
Polyamide fiber has the requirements for antioxidant and antibacterial properties when applied to produce functional textiles for heath care purposes. In this work, three natural flavonoids (baicalin, quercetin, and rutin) were used to simultaneously impart antioxidant and antibacterial functions to polyamide fiber using [...] Read more.
Polyamide fiber has the requirements for antioxidant and antibacterial properties when applied to produce functional textiles for heath care purposes. In this work, three natural flavonoids (baicalin, quercetin, and rutin) were used to simultaneously impart antioxidant and antibacterial functions to polyamide fiber using an adsorption technology. The relations of the chemical structures of flavonoids with their adsorption capability, adsorption mechanisms, and antioxidant and antibacterial activities were discussed. The Langmuir–Nernst adsorption model fitted the adsorption isotherms of the three flavonoids well. The adsorption kinetics of the three flavonoids conformed to the pseudo second-order kinetic model. Quercetin exhibited the highest affinity and adsorption capability, and imparted the highest antioxidant and antibacterial activities to polyamide fiber; and moreover, its antioxidant and antibacterial functions had good washing durability. This study demonstrates that the treatment using natural flavonoids is an effective way to exhance the health care functions of polyamide fiber. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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12 pages, 1367 KiB  
Article
Antioxidant Properties of a Traditional Vine Tea, Ampelopsis grossedentata
by Kun Xie, Xi He, Keyu Chen, Jihua Chen, Kozue Sakao and De-Xing Hou
Antioxidants 2019, 8(8), 295; https://doi.org/10.3390/antiox8080295 - 9 Aug 2019
Cited by 48 | Viewed by 6146
Abstract
Ampelopsis grossedentata, also called vine tea, has been used as a traditional beverage in China for centuries. Vine tea contains rich polyphenols and shows benefit to human health, but the chemical and antioxidant properties of vine tea polyphenols from different locations remain [...] Read more.
Ampelopsis grossedentata, also called vine tea, has been used as a traditional beverage in China for centuries. Vine tea contains rich polyphenols and shows benefit to human health, but the chemical and antioxidant properties of vine tea polyphenols from different locations remain unclear. This study aims to investigate the chemical and antioxidant properties of vine tea from three major production areas in China including Guizhou, Hunan, and Guangxi Provinces. The highest amount of polyphenol from vine tea was extracted by 70% ethanol at 70 °C for 40 min with ultrasonic treatment. The major compound in vine tea polyphenols (VTP) was determined as dihydromyricetin (DMY) by high-performance liquid chromatography (HPLC) and the content was estimated as 21.42%, 20.17%, and 16.47% of dry weight basis from Hunan, Guizhou, and Guangxi products, respectively. The antioxidant activities were investigated in vitro and in culture hepatic cells. VTP and DMY showed strong 1,1-Diphenyl-2-picrylhydrazyl free radical (DPPH) scavenging ability and high oxygen radical absorption capacity (ORAC) value in vitro. VTP and DMY also increased the level of nicotinamide adenine dinucleotide phosphate (NADPH):quinone oxidoreductase (NQO1) in HepG2 cells. Moreover, VTP and DMY enhanced the level of nuclear factor erythroid 2-related factor 2 (Nrf2) and reduced the level of Kelch-like ECH-associated protein 1 (Keap1). Taken together, our data demonstrated that the extraction of vine tea by 70% ethanol with ultrasonic treatment is a novel method to efficiently obtain components possessing stronger antioxidant activity. Furthermore, the results from the culture cells suggest that the bioactive component of vine tea might exert the antioxidant activity by activating the cellular Nrf2/Keap1 pathway. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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13 pages, 1519 KiB  
Article
Inhibition of LPS-Induced Oxidative Damages and Potential Anti-Inflammatory Effects of Phyllanthus emblica Extract via Down-Regulating NF-κB, COX-2, and iNOS in RAW 264.7 Cells
by Hui Min-David Wang, Ling Fu, Chia Chi Cheng, Rong Gao, Meng Yi Lin, Hong Lin Su, Nathania Earlene Belinda, Thi Hiep Nguyen, Wen-Hung Lin, Po Chun Lee and Liang Po Hsieh
Antioxidants 2019, 8(8), 270; https://doi.org/10.3390/antiox8080270 - 2 Aug 2019
Cited by 72 | Viewed by 7974
Abstract
Phyllanthus emblica is an edible nutraceutical and functional food in the Asia area with medicinal and nutritive importance. The fruit extract of P. emblica is currently considered to be one of the effective functional foods for flesh maintenance and disease treatments because of [...] Read more.
Phyllanthus emblica is an edible nutraceutical and functional food in the Asia area with medicinal and nutritive importance. The fruit extract of P. emblica is currently considered to be one of the effective functional foods for flesh maintenance and disease treatments because of its antioxidative and immunomodulatory properties. We examined the antioxidant abilities of the fruit extract powder by carrying out 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, iron reducing power, and metal chelating activity analysis and showed excellent antioxidative results. In 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the result showed that the samples had no cytotoxic effect on RAW 264.7 cells even at a high concentration of 2 mg/mL. To investigate its immunomodulatory function, our estimation was to treat it with lipopolysaccharide (LPS) in RAW 264.7 cells to present anti-inflammatory capacities. The extract decreased reactive oxygen species (ROS) production levels in a dose-dependent manner measured by flow cytometry. We also examined various inflammatory mRNAs and proteins, including nuclear factor-κB (NF-κB), inducible nitric oxide synthases (iNOS), and cyclooxygenase-2 (COX-2). In quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blotting assay, all three targets were decreased by the extract, also in a dose-dependent manner. In conclusion, P. emblica fruit extract powder not only lessened antioxidative stress damages, but also inhibited inflammatory reactions. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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15 pages, 2617 KiB  
Article
Antioxidant Activity of Graptopetalum paraguayense E. Walther Leaf Extract Counteracts Oxidative Stress Induced by Ethanol and Carbon Tetrachloride Co-Induced Hepatotoxicity in Rats
by Wen-Wan Chao, Shu-Ju Chen, Hui-Chen Peng, Jiunn-Wang Liao and Su-Tze Chou
Antioxidants 2019, 8(8), 251; https://doi.org/10.3390/antiox8080251 - 28 Jul 2019
Cited by 19 | Viewed by 4795
Abstract
(1) Background: Graptopetalum paraguayense E. Walther is a traditional Chinese herbal medicine. In our previous study, 50% ethanolic G. paraguayense extracts (GE50) demonstrated good antioxidant activity. (2) Methods: To investigate the hepatoprotective effects of GE50 on ethanol and carbon tetrachloride (CCl4) [...] Read more.
(1) Background: Graptopetalum paraguayense E. Walther is a traditional Chinese herbal medicine. In our previous study, 50% ethanolic G. paraguayense extracts (GE50) demonstrated good antioxidant activity. (2) Methods: To investigate the hepatoprotective effects of GE50 on ethanol and carbon tetrachloride (CCl4) co-induced hepatic damage in rats, Sprague–Dawley rats were randomly divided into five groups (Control group; GE50 group, 0.25 g/100 g BW; EC group: Ethanol + CCl4, 1.25 mL 50% ethanol and 0.1 mL 20% CCl4/100 g BW; EC + GE50 group: Ethanol + CCl4 + GE50; EC + silymarin group: ethanol + CCl4 + silymarin, 20 mg/100 g BW) for six consecutive weeks. (3) Results: Compared with the control group, EC group significantly elevated the serum aspartate aminotransferase (AST), alanine aminitransferase (ALT), and lactate dehydrogenase (LDH). However, GE50 or silymarin treatment effectively reversed these changes. GE50 had a significant protective effect against ethanol + CCl4 induced lipid peroxidation and increased the levels of glutathione (GSH), vitamin C, E, total antioxidant status (TAS), and the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and glutathione S-transferases (GST). Furthermore, in EC focal group, slight fat droplet infiltration was observed in the livers, while in the GE50 or silymarin treatment groups, decreased fat droplet infiltration. HPLC phytochemical profile of GE50 revealed the presence of gallic acid, flavone, genistin, daidzin, and quercetin. (4) Conclusions: The hepatoprotective activity of GE50 is proposed to occur through the synergic effects of its chemical component, namely, gallic acid, flavone, genistin, daidzin, and quercetin. Hence, G. paraguayense can be used as a complementary and alternative therapy in the prevention of alcohol + CCl4-induced liver injury. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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15 pages, 1206 KiB  
Article
Nutritional Composition, Total Phenolic Content, Antioxidant and α-Amylase Inhibitory Activities of Different Fractions of Selected Wild Edible Plants
by Ziaul Hasan Rana, Mohammad Khairul Alam and Mohammad Akhtaruzzaman
Antioxidants 2019, 8(7), 203; https://doi.org/10.3390/antiox8070203 - 1 Jul 2019
Cited by 62 | Viewed by 7623
Abstract
Wild plants are considered the richest source of essential nutrients and other beneficial phytochemicals. Hence, the objective of this study was to evaluate the nutritional composition, antioxidant- and α-amylase inhibition activities of leaves and roots of selected Bangladeshi wild plants. These wild plants [...] Read more.
Wild plants are considered the richest source of essential nutrients and other beneficial phytochemicals. Hence, the objective of this study was to evaluate the nutritional composition, antioxidant- and α-amylase inhibition activities of leaves and roots of selected Bangladeshi wild plants. These wild plants were found to have high fiber (13.78–22.26 g/100 g), protein (7.08–21.56 g/100 g) and ash (8.21–21.43 g/100 g) contents. The total phenolic and total flavonoid contents were significantly higher in the leaves than the roots. Additionally, antioxidant activity was evaluated using ferric-reducing antioxidant power, 2, 2-diphenyl-1-picrylhydrazyl radical (DPPH) and trolox equivalent antioxidant capacity assays and was strongly correlated with phenolic compounds. The leaf extracts of the selected plants also exhibited potent α-amylase inhibition (~71%) and were significantly higher than their root counterparts. Thus, the study findings concluded that the investigated plants were good sources of fiber, protein, mineral, natural antioxidant compounds and α-amylase inhibitors, and their increased intake could provide health benefits. The principal component analysis (PCA) of analyzed variables divided the samples into three clear groups, and the first two principal components accounted for 86.05% of the total data set variance. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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13 pages, 1556 KiB  
Article
Vitis vinifera L. Leaf Extract Inhibits In Vitro Mediators of Inflammation and Oxidative Stress Involved in Inflammatory-Based Skin Diseases
by Enrico Sangiovanni, Chiara Di Lorenzo, Stefano Piazza, Yuri Manzoni, Cecilia Brunelli, Marco Fumagalli, Andrea Magnavacca, Giulia Martinelli, Francesca Colombo, Antonella Casiraghi, Gloria Melzi, Laura Marabini, Patrizia Restani and Mario Dell’Agli
Antioxidants 2019, 8(5), 134; https://doi.org/10.3390/antiox8050134 - 16 May 2019
Cited by 26 | Viewed by 6749
Abstract
Psoriasis is a chronic cutaneous condition characterized by the release of pro-inflammatory mediators and oxidative stress. The reduction of these factors is currently the most effective strategy to inhibit the symptoms of pathology. Antioxidants from natural sources are increasingly used to improve skin [...] Read more.
Psoriasis is a chronic cutaneous condition characterized by the release of pro-inflammatory mediators and oxidative stress. The reduction of these factors is currently the most effective strategy to inhibit the symptoms of pathology. Antioxidants from natural sources are increasingly used to improve skin conditions. Dried red leaves from grapevine (Vitis vinifera L., cv Teinturiers) showed anti-inflammatory and anti-bacterial activities, but their possible effects on keratinocytes have not been previously investigated. In this study we tested the ability of a water extract from grapevine leaves (VVWE) to inhibit inflammatory conditions in human keratinocytes (HaCaT cells), challenged with proinflammatory (tumor necrosis factor-α (TNF-α) or lipopolysaccharide (LPS)) or prooxidant (ultraviolet B radiation (UVB) or H2O2) mediators. VVWE inhibited interleukin-8 (IL-8) secretion induced by proinflammatory stimuli, acting on the IL-8 promoter activity, but the effect was lower when prooxidant mediators were used. The effect was partly explained by the reduction of nuclear factor-κB (NF-κB)-driven transcription and nuclear translocation. Furthermore, vascular endothelial growth factor (VEGF) secretion, a regulator of angiogenesis, was inhibited by VVWE, but not matrix metalloproteinase-9 (MMP-9), a protease involved in matrix remodeling. VVWE, assayed on Franz diffusion cell system, showed a marked reduction of High Performance Liquid Chromatography (HPLC)-identified compounds. Pure molecules individually failed to reduce TNF-α-induced IL-8 release, suggesting synergistic effects or the presence of other bioactive compounds still unknown. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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16 pages, 3389 KiB  
Article
Natural Antioxidant Resveratrol Suppresses Uterine Fibroid Cell Growth and Extracellular Matrix Formation In Vitro and In Vivo
by Hsin-Yuan Chen, Po-Han Lin, Yin-Hwa Shih, Kei-Lee Wang, Yong-Han Hong, Tzong-Ming Shieh, Tsui-Chin Huang and Shih-Min Hsia
Antioxidants 2019, 8(4), 99; https://doi.org/10.3390/antiox8040099 - 12 Apr 2019
Cited by 32 | Viewed by 9520
Abstract
Resveratrol (RSV) is a polyphenolic phytoalexin found in peanuts, grapes, and other plants. Uterine fibroids (UF) are benign growths that are enriched in extracellular matrix (ECM) proteins. In this study, we aimed to investigate the effects of RSV on UF using in vivo [...] Read more.
Resveratrol (RSV) is a polyphenolic phytoalexin found in peanuts, grapes, and other plants. Uterine fibroids (UF) are benign growths that are enriched in extracellular matrix (ECM) proteins. In this study, we aimed to investigate the effects of RSV on UF using in vivo and in vitro approaches. In mouse xenograft models, tumors were implanted through the subcutaneous injection of Eker rat-derived uterine leiomyoma cells transfected with luciferase (ELT-3-LUC) in five-week-old female nude (Foxn1nu) mice. When the tumors reached a size of 50–100 mm3, the mice were randomly assigned to intraperitoneal treatment with RSV (10 mg·kg−1) or vehicle control (dimethyl sulfoxide). Tumor tissues were assayed using an immunohistochemistry analysis. We also used primary human leiomyoma cells as in vitro models. Cell viability was determined using the sodium bicarbonate and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The protein expression was assayed using Western blot analysis. The messenger ribonucleic acid (mRNA) expression was assayed using quantitative reverse transcription–polymerase chain reaction (qRT–PCR). Cell apoptosis was assayed using Annexin V-fluorescein isothiocyanate (FITC) and propidium iodide (PI) and Hoechst 33342 staining. RSV significantly suppressed tumor growth in vivo and decreased the proportion of cells showing expression of proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (α-SMA). In addition, RSV decreased the protein expression of PCNA, fibronectin, and upregulated the ratio of Bax (Bcl-2-associated X) and Bcl-2 (B-cell lymphoma/leukemia 2) in vivo. Furthermore, RSV reduced leiomyoma cell viability, and decreased the mRNA levels of fibronectin and the protein expression of collagen type 1 (COL1A1) and α-SMA (ECM protein marker), as well as reducing the levels of β-catenin protein. RSV induced apoptosis and cell cycle arrest at sub-G1 phase. Our findings indicated the inhibitory effects of RSV on the ELT-3-LUC xenograft model and indicated that RSV reduced ECM-related protein expression in primary human leiomyoma cells, demonstrating its potential as an anti-fibrotic therapy for UF. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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11 pages, 5500 KiB  
Article
Inhibitory Effects of Auraptene and Naringin on Astroglial Activation, Tau Hyperphosphorylation, and Suppression of Neurogenesis in the Hippocampus of Streptozotocin-Induced Hyperglycemic Mice
by Satoshi Okuyama, Tatsumi Nakashima, Kumi Nakamura, Wakana Shinoka, Maho Kotani, Atsushi Sawamoto, Mitsunari Nakajima and Yoshiko Furukawa
Antioxidants 2018, 7(8), 109; https://doi.org/10.3390/antiox7080109 - 19 Aug 2018
Cited by 23 | Viewed by 5220
Abstract
Auraptene, a citrus-related compound, exerts anti-inflammatory effects in peripheral tissues, and we demonstrated these effects in the brains of a lipopolysaccharide-injected systemic inflammation animal model and a brain ischemic mouse model. Naringin, another citrus-related compound, has been shown to exert antioxidant effects in [...] Read more.
Auraptene, a citrus-related compound, exerts anti-inflammatory effects in peripheral tissues, and we demonstrated these effects in the brains of a lipopolysaccharide-injected systemic inflammation animal model and a brain ischemic mouse model. Naringin, another citrus-related compound, has been shown to exert antioxidant effects in several animal models. Hyperglycemia induces oxidative stress and inflammation and causes extensive damage in the brain; therefore, we herein evaluated the anti-inflammatory and other effects of auraptene and naringin in streptozotocin-induced hyperglycemic mice. Both compounds inhibited astroglial activation and the hyperphosphorylation of tau at 231 of threonine in neurons, and also recovered the suppression of neurogenesis in the dentate gyrus of the hippocampus in hyperglycemic mice. These results suggested that auraptene and naringin have potential effects as neuroprotective agents in the brain. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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10 pages, 1605 KiB  
Article
Protective Effect of Aqueous Extract from the Leaves of Justicia tranquebariesis against Thioacetamide-Induced Oxidative Stress and Hepatic Fibrosis in Rats
by Kumeshini Sukalingam, Kumar Ganesan and Baojun Xu
Antioxidants 2018, 7(7), 78; https://doi.org/10.3390/antiox7070078 - 22 Jun 2018
Cited by 35 | Viewed by 6341
Abstract
The present study aims to examine the protective effect of Justicia tranquebariesis on thioacetamide (TAA)-induced oxidative stress and hepatic fibrosis. Male Wister albino rats (150–200 g) were divided into five groups. Group 1 was normal control. Group 2 was J. tranquebariensis (400 mg/kg [...] Read more.
The present study aims to examine the protective effect of Justicia tranquebariesis on thioacetamide (TAA)-induced oxidative stress and hepatic fibrosis. Male Wister albino rats (150–200 g) were divided into five groups. Group 1 was normal control. Group 2 was J. tranquebariensis (400 mg/kg bw/p.o.)-treated control. Group 3 was TAA (100 mg/kg bw/s.c.)-treated control. Groups 4 and 5 were orally administered with the leaf extract of J. tranquebariensis (400 mg/kg bw) and silymarin (50 mg/kg bw) daily for 10 days with a subsequent administration of a single dose of TAA (100 mg/kg/s.c.). Blood and livers were collected and assayed for various antioxidant enzymes (SOD, CAT, GPx, GST, GSH, and GR). Treatment with J. tranquebariensis significantly reduced liver TBARS and enhanced the activities of antioxidant enzymes in TAA-induced fibrosis rats. Concurrently, pretreatment with J. tranquebariensis significantly reduced the elevated liver markers (AST, ALT, ALP, GGT, and TB) in the blood. In addition, J. tranquebariensis- and silymarin- administered rats demonstrated the restoration of normal liver histology and reduction in fibronectin and collagen deposition. Based on these findings, J. tranquebariensis has potent liver protective functions and can alleviate thioacetamide-induced oxidative stress, hepatic fibrosis and possible engross mechanisms connected to antioxidant potential. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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Review

Jump to: Research

26 pages, 1721 KiB  
Review
Vitamin C in Plants: From Functions to Biofortification
by Costantino Paciolla, Stefania Fortunato, Nunzio Dipierro, Annalisa Paradiso, Silvana De Leonardis, Linda Mastropasqua and Maria Concetta de Pinto
Antioxidants 2019, 8(11), 519; https://doi.org/10.3390/antiox8110519 - 29 Oct 2019
Cited by 199 | Viewed by 17619
Abstract
Vitamin C (l-ascorbic acid) is an excellent free radical scavenger, not only for its capability to donate reducing equivalents but also for the relative stability of the derived monodehydroascorbate radical. However, vitamin C is not only an antioxidant, since it is [...] Read more.
Vitamin C (l-ascorbic acid) is an excellent free radical scavenger, not only for its capability to donate reducing equivalents but also for the relative stability of the derived monodehydroascorbate radical. However, vitamin C is not only an antioxidant, since it is also a cofactor for numerous enzymes involved in plant and human metabolism. In humans, vitamin C takes part in various physiological processes, such as iron absorption, collagen synthesis, immune stimulation, and epigenetic regulation. Due to the functional loss of the gene coding for l-gulonolactone oxidase, humans cannot synthesize vitamin C; thus, they principally utilize plant-based foods for their needs. For this reason, increasing the vitamin C content of crops could have helpful effects on human health. To achieve this objective, exhaustive knowledge of the metabolism and functions of vitamin C in plants is needed. In this review, the multiple roles of vitamin C in plant physiology as well as the regulation of its content, through biosynthetic or recycling pathways, are analyzed. Finally, attention is paid to the strategies that have been used to increase the content of vitamin C in crops, emphasizing not only the improvement of nutritional value of the crops but also the acquisition of plant stress resistance. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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17 pages, 1442 KiB  
Review
Effects and Mechanisms of Tea and Its Bioactive Compounds for the Prevention and Treatment of Cardiovascular Diseases: An Updated Review
by Shi-Yu Cao, Cai-Ning Zhao, Ren-You Gan, Xiao-Yu Xu, Xin-Lin Wei, Harold Corke, Atanas G. Atanasov and Hua-Bin Li
Antioxidants 2019, 8(6), 166; https://doi.org/10.3390/antiox8060166 - 6 Jun 2019
Cited by 86 | Viewed by 13282
Abstract
Cardiovascular diseases (CVDs) are critical global public health issues with high morbidity and mortality. Epidemiological studies have revealed that regular tea drinking is inversely associated with the risk of CVDs. Additionally, substantial in vitro and in vivo experimental studies have shown that tea [...] Read more.
Cardiovascular diseases (CVDs) are critical global public health issues with high morbidity and mortality. Epidemiological studies have revealed that regular tea drinking is inversely associated with the risk of CVDs. Additionally, substantial in vitro and in vivo experimental studies have shown that tea and its bioactive compounds are effective in protecting against CVDs. The relevant mechanisms include reducing blood lipid, alleviating ischemia/reperfusion injury, inhibiting oxidative stress, enhancing endothelial function, attenuating inflammation, and protecting cardiomyocyte function. Moreover, some clinical trials also proved the protective role of tea against CVDs. In order to provide a better understanding of the relationship between tea and CVDs, this review summarizes the effects of tea and its bioactive compounds against CVDs and discusses potential mechanisms of action based on evidence from epidemiological, experimental, and clinical studies. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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23 pages, 2967 KiB  
Review
Dietary Flavonoids as Cancer Chemopreventive Agents: An Updated Review of Human Studies
by Carmen Rodríguez-García, Cristina Sánchez-Quesada and José J. Gaforio
Antioxidants 2019, 8(5), 137; https://doi.org/10.3390/antiox8050137 - 18 May 2019
Cited by 262 | Viewed by 23751
Abstract
Over the past few years, interest in health research has increased, making improved health a global goal for 2030. The purpose of such research is to ensure healthy lives and promote wellbeing across individuals of all ages. It has been shown that nutrition [...] Read more.
Over the past few years, interest in health research has increased, making improved health a global goal for 2030. The purpose of such research is to ensure healthy lives and promote wellbeing across individuals of all ages. It has been shown that nutrition plays a key role in the prevention of some chronic diseases such as obesity, cardiovascular disease, diabetes, and cancer. One of the aspects that characterises a healthy diet is a high intake of vegetables and fruits, as both are flavonoid-rich foods. Flavonoids are one of the main subclasses of dietary polyphenols and possess strong antioxidant activity and anti-carcinogenic properties. Moreover, some population-based studies have described a relationship between cancer risk and dietary flavonoid intake. In this context, the goal of this review was to provide an updated evaluation of the association between the risk of different types of cancers and dietary flavonoid intake. We analysed all relevant epidemiological studies from January 2008 to March 2019 using the PUBMED and Web of Science databases. In summary, this review concludes that dietary flavonoid intake is associated with a reduced risk of different types of cancer, such as gastric, breast, prostate, and colorectal cancers. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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20 pages, 1570 KiB  
Review
Inula L. Secondary Metabolites against Oxidative Stress-Related Human Diseases
by Wilson R. Tavares and Ana M. L. Seca
Antioxidants 2019, 8(5), 122; https://doi.org/10.3390/antiox8050122 - 6 May 2019
Cited by 45 | Viewed by 8434
Abstract
An imbalance in the production of reactive oxygen species in the body can cause an increase of oxidative stress that leads to oxidative damage to cells and tissues, which culminates in the development or aggravation of some chronic diseases, such as inflammation, diabetes [...] Read more.
An imbalance in the production of reactive oxygen species in the body can cause an increase of oxidative stress that leads to oxidative damage to cells and tissues, which culminates in the development or aggravation of some chronic diseases, such as inflammation, diabetes mellitus, cancer, cardiovascular disease, and obesity. Secondary metabolites from Inula species can play an important role in the prevention and treatment of the oxidative stress-related diseases mentioned above. The databases Scopus, PubMed, and Web of Science and the combining terms Inula, antioxidant and secondary metabolites were used in the research for this review. More than 120 articles are reviewed, highlighting the most active compounds with special emphasis on the elucidation of their antioxidative-stress mechanism of action, which increases the knowledge about their potential in the fight against inflammation, cancer, neurodegeneration, and diabetes. Alantolactone is the most polyvalent compound, reporting interesting EC50 values for several bioactivities, while 1-O-acetylbritannilactone can be pointed out as a promising lead compound for the development of analogues with interesting properties. The Inula genus is a good bet as source of structurally diverse compounds with antioxidant activity that can act via different mechanisms to fight several oxidative stress-related human diseases, being useful for development of new drugs. Full article
(This article belongs to the Special Issue Phytochemical Antioxidants and Health)
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