Antioxidants

14 pages, 824 KiB

Open AccessArticle

Comparison of Phenolic Compounds and the Antioxidant Activities of Fifteen Chrysanthemum morifolium Ramat cv. ‘Hangbaiju’ in China

by Jinyan Gong, Bingquan Chu, Lingxiao Gong, Zhongxiang Fang, Xiaoxu Zhang, Shaoping Qiu, Jingjing Wang, Yali Xiang, Gongnian Xiao, Haina Yuan and Fuping Zheng

Antioxidants 2019, 8(8), 325; https://doi.org/10.3390/antiox8080325 - 20 Aug 2019

Cited by 43 | Viewed by 4671

Abstract

This study investigated the phenolic compounds of 15 Chrysanthemum morifolium Ramat cv. ‘Hangbaiju’, including 6 ‘Duoju’ and 9 ‘Taiju’, using high performance liquid chromatography (HPLC). The antioxidant activities of these ‘Hangbaiju’ were estimated by DPPH, ABTS and FRAP assays. Results show that a [...] Read more.

This study investigated the phenolic compounds of 15 Chrysanthemum morifolium Ramat cv. ‘Hangbaiju’, including 6 ‘Duoju’ and 9 ‘Taiju’, using high performance liquid chromatography (HPLC). The antioxidant activities of these ‘Hangbaiju’ were estimated by DPPH, ABTS and FRAP assays. Results show that a total of 14 phenolic compounds were detected in these flowers, including 3 mono-caffeoylquinic acids, 3 di-caffeoylquinic acids, 1 phenolic acid and 7 flavonoids. ‘Duoju’ and ‘Taiju’ possess different concentrations of phenolic compounds, and ‘Taiju’ exhibits higher caffeoylquinic acids and stronger antioxidant activities than ‘Duoju’. Caffeoylquinic acids show a strong correlation with the antioxidant activities of the samples. Principal component analysis (PCA) reveals an obvious separation between ‘Duoju’ and ‘Taiju’, using phenolic compounds as variables. Apigenin-7-O-glucoside, 3,5-di-O-caffeoylquinic acid, luteolin and acacetin were found to be the key phenolic compounds to differentiate ‘Duoju’ from ‘Taiju’. Full article

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20 pages, 2497 KiB

Open AccessArticle

Relationships Between Chemical Structure and Antioxidant Activity of Isolated Phytocompounds from Lemon Verbena

by Noelia Sánchez-Marzo, Jesús Lozano-Sánchez, María de la Luz Cádiz-Gurrea, María Herranz-López, Vicente Micol and Antonio Segura-Carretero

Antioxidants 2019, 8(8), 324; https://doi.org/10.3390/antiox8080324 - 20 Aug 2019

Cited by 42 | Viewed by 5971

Abstract

Over the last few years, people have been concerned about the narrow relationship between nutrition and health leading to an increasing demand of nutraceutical products and functional food. Lemon verbena (Lippia citriodora Kunth) has been traditionally used for respiratory, digestive, and muscular [...] Read more.

Over the last few years, people have been concerned about the narrow relationship between nutrition and health leading to an increasing demand of nutraceutical products and functional food. Lemon verbena (Lippia citriodora Kunth) has been traditionally used for respiratory, digestive, and muscular diseases, showing effects that are promoted by the antioxidant activity of its phytoconstituents. The antioxidant power of several lemon verbena extracts has been tested but its isolated compounds activity has not been described. The aim of the present work was to isolate phytochemicals from a commercial lemon verbena extract through a semi-preparative high-performance liquid chromatography approach for further evaluation of its individual antioxidant activity using three different methods. The structure-antioxidant activity relationships revealed the influence of substitutions in the strong antioxidant power exerted by glycosylated phenylpropanoids, in contrast to the low antioxidant capacity showed by iridoids. Development of enriched extracts in these compounds could lead to greater antioxidant effects and improved functional ingredients to prevent chronic diseases. Full article

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9 pages, 3037 KiB

Open AccessReview

Antioxidant Regulation of Cell Reprogramming

by Yuichiro J. Suzuki and Nataliia V. Shults

Antioxidants 2019, 8(8), 323; https://doi.org/10.3390/antiox8080323 - 20 Aug 2019

Cited by 8 | Viewed by 4011

Abstract

Discovery of induced pluripotent stem cells (iPSCs) has revolutionized regeneration biology, providing further mechanistic insights and possible therapeutic applications. The original discovery by Yamanaka and co-workers showed that the expression of four transcription factors in fibroblasts resulted in the generation of iPSCs that [...] Read more.

Discovery of induced pluripotent stem cells (iPSCs) has revolutionized regeneration biology, providing further mechanistic insights and possible therapeutic applications. The original discovery by Yamanaka and co-workers showed that the expression of four transcription factors in fibroblasts resulted in the generation of iPSCs that can be differentiated into various cell types. This technology should be particularly useful for restoring cells with limited proliferative capacities such as adult heart muscle cells and neurons, in order to treat diseases affecting these cell types. More recently, iPSCs-mediated cell reprogramming has advanced to new technologies including direct reprogramming and pharmacological reprogramming. Direct reprogramming allows for the conversion of fibroblasts into cardiomyocytes, neurons or other cells by expressing multiple cell type-specific transcription factors without going through the production of iPSCs. Both iPSC-mediated reprogramming as well as direct reprogramming can also be promoted by a combination of small molecules, opening up a possibility for pharmacological therapies to induce cell reprogramming. However, all of these processes have been shown to be affected by reactive oxygen species that reduce the efficacies of reprogramming fibroblasts into iPSCs, differentiating iPSCs into target cells, as well as direct reprogramming. Accordingly, antioxidants have been shown to support these reprogramming processes and this review article summarizes these findings. It should be noted however, that the actions of antioxidants to support cell reprogramming may be through their ROS inhibiting abilities, but could also be due to mechanisms that are independent of classical antioxidant actions. Full article

(This article belongs to the Special Issue Novel Aspects of Redox, Antioxidant and Mitochondrial Signaling)

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12 pages, 4658 KiB

Open AccessArticle

Pharmacological Activation of Sirt1 Ameliorates Cisplatin-Induced Acute Kidney Injury by Suppressing Apoptosis, Oxidative Stress, and Inflammation in Mice

by Jung-Yeon Kim, Jungmin Jo, Kiryeong Kim, Hyun-Jin An, Mi-Gyeong Gwon, Hyemin Gu, Hyun-Ju Kim, A Young Yang, Sung-Woo Kim, Eon Ju Jeon, Jae-Hyung Park, Jaechan Leem and Kwan-Kyu Park

Antioxidants 2019, 8(8), 322; https://doi.org/10.3390/antiox8080322 - 19 Aug 2019

Cited by 55 | Viewed by 5615

Abstract

Sirtuin 1 (Sirt1) is an essential modulator of cellular metabolism and has pleiotropic effects. It was recently reported that Sirt1 overexpression in kidney tubule ameliorates cisplatin-induced acute kidney injury (AKI). However, whether pharmacological activation of Sirt1 also has a beneficial effect against the [...] Read more.

Sirtuin 1 (Sirt1) is an essential modulator of cellular metabolism and has pleiotropic effects. It was recently reported that Sirt1 overexpression in kidney tubule ameliorates cisplatin-induced acute kidney injury (AKI). However, whether pharmacological activation of Sirt1 also has a beneficial effect against the disease remains unclear. In this study, we aimed to evaluate whether SRT1720, a potent and specific activator of Sirt1, could ameliorate cisplatin-induced AKI. We found that SRT1720 treatment ameliorated cisplatin-induced acute renal failure and histopathological alterations. Increased levels of tubular injury markers in kidneys were significantly attenuated by SRT1720. SRT1720 treatment also suppressed caspase-3 activation and apoptotic cell death. Increased expression of 4-hydroxynonenal, elevated malondialdehyde level, and decreased ratio of reduced glutathione/oxidized glutathione after cisplatin injection were significantly reversed by SRT1720. In addition, SRT1720 treatment decreased renal expression of pro-inflammatory cytokines and prevented macrophage infiltration into damaged kidneys. We also showed that the therapeutic effects of SRT1720 were associated with reduced acetylation of p53 and nuclear factor kappa-B p65 and preservation of peroxisome function, as evidenced by recovered expression of markers for number and function of peroxisome. These results suggest that Sirt1 activation by SRT1720 would be a useful therapeutic option for cisplatin-induced AKI. Full article

(This article belongs to the Section Health Outcomes of Antioxidants and Oxidative Stress)

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15 pages, 1350 KiB

Open AccessArticle

Optimization of an Ultrasound-Assisted Extraction for Simultaneous Determination of Antioxidants in Sesame with Response Surface Methodology

by Dandan Wang, Liangxiao Zhang, Yueqing Xu, Xin Qi, Xuefang Wang, Xiupin Wang, Qi Zhang and Peiwu Li

Antioxidants 2019, 8(8), 321; https://doi.org/10.3390/antiox8080321 - 19 Aug 2019

Cited by 14 | Viewed by 3084

Abstract

Sesame is a nutritional agricultural product with medicinal properties. Accurate determination of micronutrients is important for the improvement of sesame quality and nutrition assessments. Our previous study showed that 10 antioxidants—d-homoproline, vitamin B₂, coniferyl aldehyde, hesperidin, phloretin, N-acetyl-l [...] Read more.

Sesame is a nutritional agricultural product with medicinal properties. Accurate determination of micronutrients is important for the improvement of sesame quality and nutrition assessments. Our previous study showed that 10 antioxidants—d-homoproline, vitamin B₂, coniferyl aldehyde, hesperidin, phloretin, N-acetyl-l-leucine, l-hyoscyamine, ferulic acid, 5-methoxypsoralen, and 8-methoxypsoralen—in sesame were potential characteristic nutrients in sesame. Herein, simultaneous detection of 10 different types of antioxidants was developed by using ultrasound-assisted extraction coupled with liquid chromatography-tandem mass spectrometry (UAE-LC-MS/MS) with the help of response surface methodology. The significant variables and levels were screened and optimized by combining the single factor experiment, Plackett–Burman test, and Box–Behnken design. The optimal conditions for extraction of target antioxidants in sesame were methanol solution of 75.0%, liquid-to-material ratio of 20:1 (mL/g), extraction temperature of 50 °C, extraction power of 410.0 W, extraction time of 65 min. The total yield of targets was 21.74 μg/g under the optimized conditions. The mobile phase used was 0.1% formic acid in acetonitrile and 0.1% formic acid in water, and the column was a Thermo Syncronis C18 reverse phase column (100 mm × 2.1 mm, 3 μm). All targets required only one injection and could be quickly separated and assayed within 7 min. The limits of detection and limits of quantification for these 10 nutritional compounds ranged from 0.01 to 0.11 µg/kg and from 0.04 to 0.34 µg/kg, respectively. The validation results indicated that the method had reasonable linearity (R² ≥ 0.9990), good recoveries (71.1%–118.3%), satisfactory intra-day precision (≤9.6%) and inter-day precision (≤12.9%), and negligible matrix effects (≤13.8%). This simultaneous quantification method was accurate, fast, and robust for the assessment of sesame nutrition. Full article

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17 pages, 4415 KiB

Open AccessArticle

Feijoa Fruit Peel: Micro-morphological Features, Evaluation of Phytochemical Profile, and Biological Properties of Its Essential Oil

by Antonella Smeriglio, Marcella Denaro, Clara De Francesco, Laura Cornara, Davide Barreca, Ersilia Bellocco, Giovanna Ginestra, Giuseppina Mandalari and Domenico Trombetta

Antioxidants 2019, 8(8), 320; https://doi.org/10.3390/antiox8080320 - 19 Aug 2019

Cited by 14 | Viewed by 5743

Abstract

Acca sellowiana (O. Berg) Burret (Feijoa) is an evergreen shrub, belonging to the Mirtaceae family. The aim of this study was to investigate the micromorphological features of the feijoa fruit peel and to evaluate the phytochemical profile, as well as the antioxidant, cytoprotective, [...] Read more.

Acca sellowiana (O. Berg) Burret (Feijoa) is an evergreen shrub, belonging to the Mirtaceae family. The aim of this study was to investigate the micromorphological features of the feijoa fruit peel and to evaluate the phytochemical profile, as well as the antioxidant, cytoprotective, and antimicrobial properties of its essential oil (EO), by several in vitro cell-free and cell-based assays. The micromorphological analysis showed several schizogenic secretory cavities, immediately below the epidermal layer. Forty compounds were identified and quantified by GC-FID and GC-MS analyses. Sesquiterpenes were the most abundant ones (76.89%), followed by monoterpene hydrocarbons (3.26%), and oxygenated monoterpenes (0.34%). The main compounds were γ-Selinene (17.39%), α-Cariophyllene (16.74%), β-Cariophyllene (10.37%), and Germacene D (5.32%). The EO showed a strong and dose-dependent antioxidant, and free-radical scavenging activity. Furthermore, it showed cytoprotective activity on the lymphocytes, that have been pre-treated with 100 μM tert-butyl-hydroperoxide (t-BOOH), as well as a decrease in intracellular reactive oxygen species (ROS), induced by t-BOOH on erythrocytes. A preliminary antimicrobial screening against GRAM+ and GRAM− bacteria, as well as on fungi highlighted that EO showed the best activity against S. aureus and C. albicans (MIC 2.7 mg/mL). In light of these results, feijoa fruit EO could find various applications, especially in the food, nutraceutical, and pharmaceutical fields. Full article

(This article belongs to the Special Issue Antioxidant and Cytoprotective Activity)

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15 pages, 3575 KiB

Open AccessArticle

Modulation of Apoptotic Cell Death and Neuroprotective Effects of Glutathione—L-Dopa Codrug Against H₂O₂-Induced Cellular Toxicity

by Sara Franceschelli, Paola Lanuti, Alessio Ferrone, Daniela Maria Pia Gatta, Lorenza Speranza, Mirko Pesce, Alfredo Grilli, Ivana Cacciatore, Emanuela Ricciotti, Antonio Di Stefano, Sebastiano Miscia, Mario Felaco and Antonia Patruno

Antioxidants 2019, 8(8), 319; https://doi.org/10.3390/antiox8080319 - 19 Aug 2019

Cited by 10 | Viewed by 3944

Abstract

The L-3,4-dihydroxyphenylalanine (LD) is the gold standard drug currently used to manage Parkinson’s disease (PD) and to control its symptoms. However, LD could cause disease neurotoxicity due to the generation of pro-oxidant intermediates deriving from its autoxidation. In order to overcome this limitation, [...] Read more.

The L-3,4-dihydroxyphenylalanine (LD) is the gold standard drug currently used to manage Parkinson’s disease (PD) and to control its symptoms. However, LD could cause disease neurotoxicity due to the generation of pro-oxidant intermediates deriving from its autoxidation. In order to overcome this limitation, we have conjugated LD to the natural antioxidant glutathione (GSH) to form a codrug (GSH-LD). Here we investigated the effect of GSH-LD on H₂O₂-induced cellular toxicity in undifferentiated and differentiated lymphoma U-937 and dopaminergic neuroblastoma SH-SY5Y cell lines, used respectively as models to study the involvement of macrophages/microglia and dopaminergic neurons in PD. We analyzed the effect of GSH-LD on apoptosis and cellular oxidative stress, both considered strategic targets for the prevention and treatment of neurodegenerative diseases. Compared to LD and GSH, GSH-LD had a stronger effect in preventing hydrogen peroxide (H₂O₂) induced apoptosis in both cell lines. Moreover, GSH-LD was able to preserve cell viability, cellular redox status, gluthation metabolism and prevent reactive oxygen species (ROS) formation, in a phosphinositide 3-kinase (PI3K)/kinase B (Akt)-dependent manner, in a neurotoxicity cellular model. Our findings indicate that the GSH-LD codrug offers advantages deriving from the additive effect of LD and GSH and it could represent a promising candidate for PD treatment. Full article

(This article belongs to the Special Issue Oxidative stress and Applied Biology)

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16 pages, 3806 KiB

Open AccessArticle

Identification and Active Evaluation of Antioxidant Peptides from Protein Hydrolysates of Skipjack Tuna (Katsuwonus pelamis) Head

by Lun Zhang, Guo-Xu Zhao, Yu-Qin Zhao, Yi-Ting Qiu, Chang-Feng Chi and Bin Wang

Antioxidants 2019, 8(8), 318; https://doi.org/10.3390/antiox8080318 - 19 Aug 2019

Cited by 79 | Viewed by 4518

Abstract

For the full use of fish by-products to produce antioxidant peptides, skipjack tuna (Katsuwonus pelamis) heads generated during can processing were defatted and hydrolyzed using the in vitro gastrointestinal (GI) digestion (pepsin–trypsin system) method and six antioxidant peptides (P1 to P6) [...] Read more.

For the full use of fish by-products to produce antioxidant peptides, skipjack tuna (Katsuwonus pelamis) heads generated during can processing were defatted and hydrolyzed using the in vitro gastrointestinal (GI) digestion (pepsin–trypsin system) method and six antioxidant peptides (P1 to P6) were purified from the head hydrolysate (KPH) using ultrafiltration and serial chromatography methods. Six isolated peptides (P1 to P6) were identified as Val-Glu-Glu (VEE, P1), Trp-Met-Phe-Asp-Trp (WMFDW, P2), Asp-Ala-Gly-Pro-Tyr-Gly-Pro-Ile (DAGPYGPI, P3), Trp-Met-Gly-Pro-Tyr (WMGPY, P4), Glu-Arg-Gly-Pro-Leu-Gly-Pro-His (ERGPLGPH, P5), and Glu-Met- Gly-Pro-Ala (EMGPA, P6), respectively, using a protein sequencer and electrospray ionization-mass spectrometer. Among skipjack tuna head hydrolysates, fractions, and six isolated peptides (P1 to P6), WMFDW (P2), WMGPY (P4), and EMGPA (P6) showed the highest radical scavenging activities on 2,2-diphenyl-1-picrylhydrazyl (DPPH) (EC₅₀ values of 0.31, 0.33, and 0.46 mg/mL for WMFDW, WMGPY, and EMGPA, respectively), hydroxyl (EC₅₀ values of 0.30, 0.43, and 0.52 mg/mL for WMFDW, WMGPY, and EMGPA, respectively), and superoxide anion (EC₅₀ values of 0.56, 0.38, and 0.71 mg/mL for WMFDW, WMGPY, and EMGPA, respectively). Moreover, WMFDW, WMGPY, and EMGPA showed strong capability in reducing power and lipd peroxidation inhibition in the linoleic acid system. In addition, WMFDW, WMGPY, and EMGPA can retain strong antioxidant activity at temperatures lower than 60 °C and pH values ranged from 5 to 9. The results showed that six isolated peptides (P1 to P6) from skipjack tuna heads, especially WMFDW, WMGPY, and EMGPA, might be applied in health care products acting as powerful antioxidant agents. Full article

(This article belongs to the Special Issue Extraction of Antioxidants from Food Waste)

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18 pages, 540 KiB

Open AccessArticle

Complex Evaluation of Antioxidant Capacity of Milk Thistle Dietary Supplements

by Jitka Viktorova, Milena Stranska-Zachariasova, Marie Fenclova, Libor Vitek, Jana Hajslova, Vladimir Kren and Tomas Ruml

Antioxidants 2019, 8(8), 317; https://doi.org/10.3390/antiox8080317 - 18 Aug 2019

Cited by 32 | Viewed by 5129

Abstract

Numerous in vitro assays are used to characterize the antioxidant properties of natural-based matrices. However, many of them generate contradictory and non-compliant results. In our study, we focused on the characterization of traditionally used biochemical (2,2′-azino-bis-(3-ethylbenzothiazoline-6 sulfonic acid) (ABTS), Oxygen Radical [...] Read more.

Numerous in vitro assays are used to characterize the antioxidant properties of natural-based matrices. However, many of them generate contradictory and non-compliant results. In our study, we focused on the characterization of traditionally used biochemical (2,2′-azino-bis-(3-ethylbenzothiazoline-6 sulfonic acid) (ABTS), Oxygen Radical Absorption Capacity (ORAC), and 2,2-diphenyl-1-picrylhydrazyl (DPPH)) and cellular (CAA) antioxidant tests on a broad set of milk thistle dietary supplements containing silymarin. In addition to 26 commercially available preparations, also the natural silymarin extract available from Sigma Aldrich, St. Louis, MI, USA, and a model mixture of pure flavonoid/flavonolignans mimicking the silymarin composition were investigated as control samples. Significant differences in the antioxidant capacity of the supplements were observed. Unlike the DPPH, the results of the ABTS and ORAC methods correlated with the silymarin components determined by U-HPLC-HRMS/MS. The responses in CAA were considerably lower than in other assays. Silymarin exhibited a significantly higher antioxidant capacity than the artificially prepared flavonoid/flavonolignans mixture in all tests, indicating possible presence of other antioxidants of natural origin. The follow-up U-HPLC-HRMS/MS screening revealed the presence of tens of non-silymarin compounds with reported antioxidant activity (not only in the silymarin extract, but also in the milk thistle preparations). The sum of the total phenolics and the sum of the simple phenolics correlated with CAA results more than silymarin. Full article

(This article belongs to the Special Issue Antioxidant and Cytoprotective Activity)

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6 pages, 182 KiB

Open AccessEditorial

Pros and Cons of Use of Mitochondria-Targeted Antioxidants

by Egor Y. Plotnikov and Dmitry B. Zorov

Antioxidants 2019, 8(8), 316; https://doi.org/10.3390/antiox8080316 - 17 Aug 2019

Cited by 22 | Viewed by 4531

Abstract

Mitochondrial targeting is a novel strategy, which addresses pathologies originating from mitochondrial dysfunction. Here, one of the most potent therapeutics arises from the group of mitochondria-targeted antioxidants, which specifically quench mitochondrial reactive oxygen species (ROS). They show very high efficacy in the treatment [...] Read more.

Mitochondrial targeting is a novel strategy, which addresses pathologies originating from mitochondrial dysfunction. Here, one of the most potent therapeutics arises from the group of mitochondria-targeted antioxidants, which specifically quench mitochondrial reactive oxygen species (ROS). They show very high efficacy in the treatment of a diverse array of pathologies encountered in this Special Issue of Antioxidants. However, despite very encouraging results in the use of mitochondria-targeted antioxidants, the mechanistic principle of delivering these agents is, to some extent, counterproductive to the goal of selectively treating a population of damaged mitochondria. The main problem that arises is that injured mitochondria may carry a lower membrane potential when compared with normal ones and as a result, injured mitochondria are capable of taking up less therapeutic antioxidants than healthy mitochondria. Another problem is that the intracellular activity of mitochondrial ROS differs from cytosolic ROS in that they carry specific intracellular functions which are maintained at a delicate equilibrium and which may be disturbed under careless use of antioxidant doses. Consequently, understanding the overall benefit of targeting dysfunctional mitochondria in pathological tissue requires furthering the development of alternative techniques to target mitochondria. Full article

(This article belongs to the Special Issue Mitochondria-Targeted Antioxidants)

25 pages, 1690 KiB

Open AccessReview

Cysteine Glutathionylation Acts as a Redox Switch in Endothelial Cells

by Agathe Lermant and Colin E. Murdoch

Antioxidants 2019, 8(8), 315; https://doi.org/10.3390/antiox8080315 - 16 Aug 2019

Cited by 33 | Viewed by 7094

Abstract

Oxidative post-translational modifications (oxPTM) of receptors, enzymes, ion channels and transcription factors play an important role in cell signaling. oxPTMs are a key way in which oxidative stress can influence cell behavior during diverse pathological settings such as cardiovascular diseases (CVD), cancer, neurodegeneration [...] Read more.

Oxidative post-translational modifications (oxPTM) of receptors, enzymes, ion channels and transcription factors play an important role in cell signaling. oxPTMs are a key way in which oxidative stress can influence cell behavior during diverse pathological settings such as cardiovascular diseases (CVD), cancer, neurodegeneration and inflammatory response. In addition, changes in oxPTM are likely to be ways in which low level reactive oxygen and nitrogen species (RONS) may contribute to redox signaling, exerting changes in physiological responses including angiogenesis, cardiac remodeling and embryogenesis. Among oxPTM, S-glutathionylation of reactive cysteines emerges as an important regulator of vascular homeostasis by modulating endothelial cell (EC) responses to their local redox environment. This review summarizes the latest findings of S-glutathionylated proteins in major EC pathways, and the functional consequences on vascular pathophysiology. This review highlights the diversity of molecules affected by S-glutathionylation, and the complex consequences on EC function, thereby demonstrating an intricate dual role of RONS-induced S-glutathionylation in maintaining vascular homeostasis and participating in various pathological processes. Full article

(This article belongs to the Special Issue Post-Translational Protein Modifications in Oxidative Stress)

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13 pages, 1874 KiB

Open AccessArticle

Inclusion Complexes of Lycopene and β-Cyclodextrin: Preparation, Characterization, Stability and Antioxidant Activity

by Haixiang Wang, Shaofeng Wang, Hua Zhu, Suilou Wang and Jiudong Xing

Antioxidants 2019, 8(8), 314; https://doi.org/10.3390/antiox8080314 - 16 Aug 2019

Cited by 33 | Viewed by 4569

Abstract

In this study, the inclusion complexes of lycopene with β-cyclodextrin (β-CD) were prepared by the precipitation method. Then the inclusion complexes were characterized by the scanning electron microscopy (SEM), ultraviolet-visible spectroscopy (UV), microscopic observation, liquid chromatography, differential scanning calorimetry (DSC) and phase-solubility study. [...] Read more.

In this study, the inclusion complexes of lycopene with β-cyclodextrin (β-CD) were prepared by the precipitation method. Then the inclusion complexes were characterized by the scanning electron microscopy (SEM), ultraviolet-visible spectroscopy (UV), microscopic observation, liquid chromatography, differential scanning calorimetry (DSC) and phase-solubility study. Moreover, the stability and antioxidant activity were tested. The results showed that lycopene was embedded into the cavity of β-CD with a 1:1 stoichiometry. Moreover, the thermal and irradiant stabilities of lycopene were all significantly increased by the formation of lycopene/β-CD inclusion complexes. Antioxidant properties of lycopene and its inclusion complexes were evaluated on the basis of measuring the scavenging activity for 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide anion radicals. The results showed that the scavenging activity of DPPH radicals was obviously increased by the formation of the inclusion complex with β-cyclodextrin at concentrations of 5–30 μg/mL, however, some significant positive effects on the scavenging activity of hydroxyl and superoxide anion radicals were not observed and the reasons are worth further study. Full article

(This article belongs to the Special Issue Carotenoids)

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10 pages, 271 KiB

Open AccessArticle

Seed-Roasting Process Affects Oxidative Stability of Cold-Pressed Oils

by Maria Barbara Różańska, Przemysław Łukasz Kowalczewski, Jolanta Tomaszewska-Gras, Krzysztof Dwiecki and Sylwia Mildner-Szkudlarz

Antioxidants 2019, 8(8), 313; https://doi.org/10.3390/antiox8080313 - 16 Aug 2019

Cited by 38 | Viewed by 3967

Abstract

The oxidative stability of vegetable oils mainly depends on their fatty acid composition, their degree of unsaturation, and the presence of compounds with antioxidant activity. This paper reports on the effects of the process of roasting oil seeds, prior to pressing them, on [...] Read more.

The oxidative stability of vegetable oils mainly depends on their fatty acid composition, their degree of unsaturation, and the presence of compounds with antioxidant activity. This paper reports on the effects of the process of roasting oil seeds, prior to pressing them, on the basic characteristics of the oils produced and their oxidative stability. The differential scanning calorimetry (DSC) technique was used to study the process of oxidation of the oil samples in an oxygen-flow cell. Chromatographic analysis revealed that roasting the seeds increased the levels of chlorophyll and β-carotene in all the cold-pressed oils. Similar results were observed for the oil’s antioxidant activity, measured by the scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical method. Our results also indicated that roasting seeds prior to pressing them for oil had a positive effect on the oil’s stability, as determined by the DSC method. This manifested in both the extension of oxidation induction time and the final oxidation time. Full article

21 pages, 2153 KiB

Open AccessArticle

The Effect of Dietary Quercetin on the Glutathione Redox System and Small Intestinal Functionality of Weaned Piglets

by Jeroen Degroote, Hans Vergauwen, Noémie Van Noten, Wei Wang, Stefaan De Smet, Chris Van Ginneken and Joris Michiels

Antioxidants 2019, 8(8), 312; https://doi.org/10.3390/antiox8080312 - 16 Aug 2019

Cited by 13 | Viewed by 5506

Abstract

Quercetin has been shown to alleviate mucosal damage and modulate the glutathione (GSH) redox system in the colon of rodents. In the current study, we assessed whether quercetin was able to mitigate small intestinal dysfunction in weaned pigs. Here, 224 weaned piglets were [...] Read more.

Quercetin has been shown to alleviate mucosal damage and modulate the glutathione (GSH) redox system in the colon of rodents. In the current study, we assessed whether quercetin was able to mitigate small intestinal dysfunction in weaned pigs. Here, 224 weaned piglets were fed a diet containing quercetin at either 0, 100, 300, or 900 mg/kg diet until d14 post-weaning, followed by a common basal diet until d42. Eight animals per treatment were sampled at d5 and d14 post-weaning. In these animals, the small intestinal histomorphology, barrier function, and protein abundance of occludin, caspase-3, and proliferating cell nuclear antigen were assessed. None of these parameters were affected, and neither did quercetin improve performance up to d42 post-weaning. The GSH redox system was evaluated in blood, small intestinal mucosa, and liver. Quercetin did not affect the glutathione peroxidase, glutathione reductase, and glutamate–cysteine ligase activity in these tissues. In contrast, the hepatic glutathione transferase (GST) activity was significantly increased by quercetin supplementation at d5 post-weaning of 100, 300, and 900 mg/kg. Importantly, d5 was characterized by a more oxidized GSH redox status. To conclude, dietary quercetin had little effect on the small intestine, but did upregulate hepatic GST in the occurrence of redox disturbance. Full article

(This article belongs to the Special Issue Redox Balance in Animal Physiology)

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15 pages, 4435 KiB

Open AccessArticle

Bioactive Amines Screening in Four Genotypes of Thermally Processed Cauliflower

by Marla Silvia Diamante, Cristine Vanz Borges, Mônica Bartira da Silva, Igor Otavio Minatel, Camila Renata Corrêa, Hector Alonzo Gomez Gomez and Giuseppina Pace Pereira Lima

Antioxidants 2019, 8(8), 311; https://doi.org/10.3390/antiox8080311 - 15 Aug 2019

Cited by 13 | Viewed by 3883

Abstract

Biogenic amines are important indicators of food quality with recognized antioxidant capacity. Diets that are rich in these compounds promote several benefits for human health, although the consumption in excess may result in food poisoning. This study aims to screen the levels of [...] Read more.

Biogenic amines are important indicators of food quality with recognized antioxidant capacity. Diets that are rich in these compounds promote several benefits for human health, although the consumption in excess may result in food poisoning. This study aims to screen the levels of biogenic amines in four colored cauliflowers, before and after cooking (boiling, steaming, and microwaving). In addition, the levels of tryptophan and 5-hydroxytryptophan, two serotonin precursors, were analyzed. Our results reveal that thermal processing shows a tendency to increase tryptophan levels and reduce 5-hydroxytryptophan in colored cauliflowers. A reduction of the tryptophan and increase in serotonin contents in ‘Cheddar’, steamed or microwaved, was observed. A higher level of histamine was observed in the genotype ‘Forata’ after cooking, whereas melatonin levels were higher after steaming and microwaving. The lowest levels of biogenic amines and amino acids were observed in ‘Graffiti’. All the colored cauliflowers that were analyzed presented a chemical quality index (CQI) below the pre-established limits, indicating that are safe for consumption, even after cooking. We conclude that the levels of biogenic amines and amino acids in colored cauliflower are safe for human consumption and do not present health risks. Therefore, the consumption of these genotypes, raw or cooked, is a good source of bioactive compounds. Full article

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14 pages, 2732 KiB

Open AccessArticle

Myrciaria tenella (DC.) O. Berg (Myrtaceae) Leaves as a Source of Antioxidant Compounds

by Ana Raquel Carneiro Ribeiro, Maria Lúcia da Silva Cordeiro, Larissa Marina Pereira Silva, Cesar Orlando Munoz Cadavid, Ricardo Basílio de Oliveira Caland, Marília Medeiros Fernandes-Negreiros, Moacir Fernandes Queiroz, Jefferson da Silva Barbosa, Cicero Flavio Soares Aragão, Silvana Maria Zucolotto, Riva de Paula Oliveira, Hugo Alexandre Oliveira Rocha and Kátia Castanho Scortecci

Antioxidants 2019, 8(8), 310; https://doi.org/10.3390/antiox8080310 - 15 Aug 2019

Cited by 9 | Viewed by 4162

Abstract

Myrciaria species are widely studied to identify their chemical composition and evaluate their biological activity. Since evidence supporting the potential antioxidant and antiproliferative activity of Myrciaria tenella is lacking, the aim of this work was to evaluate these activities in six different leaf [...] Read more.

Myrciaria species are widely studied to identify their chemical composition and evaluate their biological activity. Since evidence supporting the potential antioxidant and antiproliferative activity of Myrciaria tenella is lacking, the aim of this work was to evaluate these activities in six different leaf extracts: hexane (CHE), chloroform (CCE), ethanolic (CEE), methanolic (CME), aqueous final (CFAE), and only aqueous (CAE). The presence of phenolic compounds, tannin, saponin, and ursolic acid was determined by thin layer chromatography (TLC). CEE, CME, and CFAE showed in vitro antioxidant activity at the initiation, propagation, and termination stages of oxidative damage. Moreover, no toxicity was observed in the 3T3 non-cancerous cell line. On the other hand, all extracts promoted cell death in the tumor cell lines human cervical adenocarcinoma cell line (HeLa) and human stomach gastric adenocarcinoma cell line (AGS). Based on these results, the effect of CEE on the AGS cell line was analyzed using flow cytometry, and necrosis and late apoptosis were observed. Finally, the Caenorhabditis elegans model showed that CEE was able to reduce the basal reactive oxygen species (ROS) level. Ultra-performance liquid chromatography (UPLC) analysis showed rutin as the major compound in CEE. Therefore, Myrciaria tenella fresh leaves may be potential sources of molecules possessing antioxidant and antiproliferative activities. Full article

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12 pages, 297 KiB

Open AccessArticle

In Vitro and In Vivo Antioxidant Properties of Taraxacum officinale in Nω-Nitro-l-Arginine Methyl Ester (L-NAME)-Induced Hypertensive Rats

by Olukayode O. Aremu, Adebola O. Oyedeji, Opeoluwa O. Oyedeji, Benedicta N. Nkeh-Chungag and Constance R. Sewani Rusike

Antioxidants 2019, 8(8), 309; https://doi.org/10.3390/antiox8080309 - 15 Aug 2019

Cited by 18 | Viewed by 7239

Abstract

Oxidative stress has gained attention as one of the fundamental mechanisms responsible for the development of hypertension. The present study investigated in vitro and in vivo antioxidant effects of 70% ethanol-water (v/v) leaf and root extracts of T. officinale [...] Read more.

Oxidative stress has gained attention as one of the fundamental mechanisms responsible for the development of hypertension. The present study investigated in vitro and in vivo antioxidant effects of 70% ethanol-water (v/v) leaf and root extracts of T. officinale (TOL and TOR, respectively). Total phenolic and flavonoid content of plant extracts were assessed using Folin Ciocalteau and aluminium chloride colorimetric methods; while, 2,2-diphenyl-1-picrlhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and ferric reducing antioxidant power (FRAP) protocols were used to determine the free radical scavenging and total antioxidant capacities (TAC), respectively. The in vivo total antioxidant capacity and malondialdehyde acid (MDA) levels for lipid peroxidation tests were performed on organ homogenate samples from Nω-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive rats treated with leaf extract, TOL (500 mg/kg/day) and TOR (500 mg/kg/day) for 21 days. Results showed that compared to TOR, TOL possessed significantly higher (p < 0.01) polyphenol (4.35 ± 0.15 compared to 1.14 ± 0.01) and flavonoid (23.17 ± 0.14 compared to 3 ± 0.05) content; free radical scavenging activity (EC₅₀ 0.37 compared to 1.34 mg/mL) and total antioxidant capacities (82.56% compared to 61.54% ABTS, and 156 ± 5.28 compared to 40 ± 0.31 FRAP) and both extracts showed no toxicity (LD₅₀ > 5000 mg/kg). TOL and TOR significantly (p < 0.01) elevated TAC and reduced MDA levels in targets organs. In conclusion, T. officinale leaf extract possesses significant anti-oxidant effects which conferred significant in vivo antioxidant protection against free radical-mediated oxidative stress in L-NAME-induced hypertensive rats. Full article

(This article belongs to the Section Health Outcomes of Antioxidants and Oxidative Stress)

12 pages, 563 KiB

Open AccessArticle

Anti-Hyperglycemic and Anticholinergic Effects of Natural Antioxidant Contents in Edible Flowers

by Paulina Nowicka and Aneta Wojdyło

Antioxidants 2019, 8(8), 308; https://doi.org/10.3390/antiox8080308 - 15 Aug 2019

Cited by 55 | Viewed by 4960

Abstract

In this study, 16 selected edible flowers were evaluated for their content of bioactive compounds (polyphenols, carotenoids, triterpenoids) and for their anti-diabetic (ability to inhibit α-amylase and α-glucosidases) and anti-aging (ability to inhibit acetylcholinesterase and butyrylcholinesterase) activities. Most of the flowers analyzed in [...] Read more.

In this study, 16 selected edible flowers were evaluated for their content of bioactive compounds (polyphenols, carotenoids, triterpenoids) and for their anti-diabetic (ability to inhibit α-amylase and α-glucosidases) and anti-aging (ability to inhibit acetylcholinesterase and butyrylcholinesterase) activities. Most of the flowers analyzed in this study have not been examined in this respect until now. Contents of the analyzed bioactive compounds differed significantly among the flowers. In particular, the highest contents of carotenoids and triterpenoids were determined in marigold, arnica, lavender, and daisy; in turn, the highest contents of phenolic acids, procyanidin polymers, and total polyphenols were assayed in hawthorn, primrose, and linden blossom. There was a positive correlation between the content of isoprenoids in edible flowers and their anti-aging activity, and between the content of polymeric procyanidins and flowers’ ability to inhibit α-glucosidase. In conclusion, edible flowers may be used to produce functional foods as well as for medical purposes. Full article

(This article belongs to the Section Natural and Synthetic Antioxidants)

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23 pages, 2141 KiB

Open AccessArticle

Caffeoylquinic Acids and Flavonoids of Fringed Sagewort (Artemisia frigida Willd.): HPLC-DAD-ESI-QQQ-MS Profile, HPLC-DAD Quantification, in Vitro Digestion Stability, and Antioxidant Capacity

by Daniil N. Olennikov, Nina I. Kashchenko, Nadezhda K. Chirikova, Aina G. Vasil’eva, Aydan I. Gadimli, Javanshir I. Isaev and Cecile Vennos

Antioxidants 2019, 8(8), 307; https://doi.org/10.3390/antiox8080307 - 14 Aug 2019

Cited by 36 | Viewed by 5265

Abstract

Fringed sagewort (Artemisia frigida Willd., Compositae family) is a well-known medicinal plant in Asian medical systems. Fifty-nine hydroxycinnamates and flavonoids have been found in A. frigida herbs of Siberian origin by high-performance liquid chromatography with diode array and electrospray triple quadrupole mass [...] Read more.

Fringed sagewort (Artemisia frigida Willd., Compositae family) is a well-known medicinal plant in Asian medical systems. Fifty-nine hydroxycinnamates and flavonoids have been found in A. frigida herbs of Siberian origin by high-performance liquid chromatography with diode array and electrospray triple quadrupole mass detection (HPLC-DAD-ESI-QQQ-MS). Their structures were determined after mass fragmentation analysis as caffeoylquinic acids, flavone O-/C-glycosides, flavones, and flavonol aglycones. Most of the discovered components were described in A. frigida for the first time. It was shown that flavonoids with different types of substitution have chemotaxonomic significance for species of Artemisia subsection Frigidae (section Absinthium). After HPLC-DAD quantification of 16 major phenolics in 21 Siberian populations of A. frigida and subsequent principal component analysis, we found substantial variation in the selected compounds, suggesting the existence of two geographical groups of A. frigida. The antioxidant activity of A. frigida herbal tea was determined using 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH^•) and hydrophilic/lipophilic oxygen radical absorbance capacity (ORAC) assays and DPPH^•-HPLC profiling, revealing it to be high. The effect of digestive media on the phenolic profile and antioxidant capacity of A. frigida herbal tea was assessed under simulated gastrointestinal digestion. We found a minor reduction in caffeoylquinic acid content and ORAC values, but remaining levels were satisfactory for antioxidant protection. These results suggest that A. frigida and its food derivate herbal tea could be recommended as new plant antioxidants rich in phenolics. Full article

(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)

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14 pages, 1711 KiB

Open AccessArticle

Protective Effects of Melon Extracts on Bone Strength, Mineralization, and Metabolism in Rats with Ovariectomy-Induced Osteoporosis

by Bongju Kim, Sung-Ho Lee, Su-Jin Song, Won Hyeon Kim, Eun-Sung Song, Jae-Chang Lee, Sung-Jae Lee, Dong-Wook Han and Jong-Ho Lee

Antioxidants 2019, 8(8), 306; https://doi.org/10.3390/antiox8080306 - 14 Aug 2019

Cited by 12 | Viewed by 3598

Abstract

A polyphenolic extract from melon (Cucumis melo L.), as a potential source of natural antioxidants, has been reported to have a positive effect on osteoblast activity. In this study, the protective effects of heat-treated melon extract (ECO-A) on bone strength, mineralization, and [...] Read more.

A polyphenolic extract from melon (Cucumis melo L.), as a potential source of natural antioxidants, has been reported to have a positive effect on osteoblast activity. In this study, the protective effects of heat-treated melon extract (ECO-A) on bone strength, mineralization, and metabolism were examined in osteoporotic rat models. Osteoporosis was induced by ovariectomy (OVX) in female rats and then maintained for 8 weeks, along with the ingestion of phosphate-buffered saline (PBS, OVXP) or ECO-A (OVXE) for an additional 4 weeks. At a pre-determined timepoint, bone strengths, as well as bone mineral contents (BMC) and the density (BMD) of femurs and/or lumbar spines extracted from each animal, were measured by a mechanical test and dual-energy X-ray absorptiometry, respectively. Moreover, several biochemical markers for bone turnover were analyzed by respective colorimetric assay kits in addition to clinical analyses. The maximum load and stiffness of femurs from the OVXE group were found to be significantly higher than the other groups. Furthermore, the OVXE group showed significantly higher BMC, BMD, and bone volume than the OVX and OVXP groups, which were comparable to the non-OVX (sham) group. The levels of bone formation and resorption markers in the OVXE group were similar to the sham group, but significantly different from other groups. In conclusion, these results suggest that ECO-A can play potentially positive roles in the protection of bone loss in rats with OVX-induced osteoporosis. Full article

(This article belongs to the Special Issue Natural Products in Health Promotion and Disease Prevention)

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18 pages, 2897 KiB

Open AccessArticle

Effect of Neem (Azadirachta indica L.) on Lipid Oxidation in Raw Chilled Beef Patties

by Manel Ouerfelli, Juliana Villasante, Leila Bettaieb Ben Kaâb and MaríaPilar Almajano

Antioxidants 2019, 8(8), 305; https://doi.org/10.3390/antiox8080305 - 14 Aug 2019

Cited by 16 | Viewed by 6314

Abstract

The aim of this study was to determine the total polyphenol content, radical scavenging and antimicrobial activities of Azadirachta indica (A. indica) and to evaluate their effect on shelf-life stability of raw beef patties during refrigerated storage at 4 ± 1 [...] Read more.

The aim of this study was to determine the total polyphenol content, radical scavenging and antimicrobial activities of Azadirachta indica (A. indica) and to evaluate their effect on shelf-life stability of raw beef patties during refrigerated storage at 4 ± 1 °C. During 11 days of storage, the antioxidant effect of A. indica on ground beef meat was investigated by the determination of lipid oxidation, pH, anti-radical activity, color, hexanal content, and microbial growth. The results obtained showed that fresh A. indica leaves and synthetic conservative behaved in the same way and retarded the lipid oxidation of chilled beef patties while increasing their pH (5.40 and 5.45, respectively). It can also be said that A. indica limited the loss of color, reduced the metmyoglobin formation (36.70%) and had a significant effect on bacterial growth and hexanal content. In addition, the results obtained through anti-radical and antimicrobial properties showed proportional values of total polyphenol content and radical scavenging activity of leaf extracts as they showed their antimicrobial effect against some bacteria such as Staphylococcus aureus and Micrococcus luteus, among others. These results support the involvement of A. indica in the food industry as a natural antioxidant that could replace synthetic ones. Full article

(This article belongs to the Special Issue Protein and Lipid Oxidation in Meat and Meat Products)

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19 pages, 1859 KiB

Open AccessArticle

A Green Ultrasound-Assisted Extraction Optimization of the Natural Antioxidant and Anti-Aging Flavonolignans from Milk Thistle Silybum marianum (L.) Gaertn. Fruits for Cosmetic Applications

by Samantha Drouet, Emilie A. Leclerc, Laurine Garros, Duangjai Tungmunnithum, Atul Kabra, Bilal Haider Abbasi, Éric Lainé and Christophe Hano

Antioxidants 2019, 8(8), 304; https://doi.org/10.3390/antiox8080304 - 14 Aug 2019

Cited by 30 | Viewed by 5545

Abstract

Silybum marianum (L.) Gaertn. (aka milk thistle) constitutes the source of silymarin (SILM), a mixture of different flavonolignans and represents a unique model for their extraction. Here we report on the development and validation of an ultrasound-assisted extraction (UAE) method of S. marianum [...] Read more.

Silybum marianum (L.) Gaertn. (aka milk thistle) constitutes the source of silymarin (SILM), a mixture of different flavonolignans and represents a unique model for their extraction. Here we report on the development and validation of an ultrasound-assisted extraction (UAE) method of S. marianum flavonolignans follow by their quantification using LC system. The optimal conditions of this UAE method were: aqueous EtOH 54.5% (v/v) as extraction solvent, with application of an ultrasound (US) frequency of 36.6 kHz during 60 min at 45 °C with a liquid to solid ratio of 25:1 mL/g dry weight (DW). Following its optimization using a full factorial design, the extraction method was validated according to international standards of the association of analytical communities (AOAC) to ensure precision and accuracy in the quantitation of each component of the SILM mixture. The efficiency of this UAE was compared with maceration protocol. Here, the optimized and validated conditions of the UAE allowed the highest extraction yields of SILM and its constituents in comparison to maceration. During UAE, the antioxidant capacity of the extracts was retained, as confirmed by the in vitro assays CUPRAC (cupric ion reducing antioxidant capacity) and inhibition of AGEs (advanced glycation end products). The skin anti-aging potential of the extract obtained by UAE was also confirmed by the strong in vitro cell-free inhibition capacity of both collagenase and elastase. To summarize, the UAE procedure presented here is a green and efficient method for the extraction and quantification of SILM and its constituents from the fruits of S. marianum, making it possible to generate extracts with attractive antioxidant and anti-aging activities for future cosmetic applications. Full article

(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)

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19 pages, 1310 KiB

Open AccessArticle

Antioxidant, Anti-Inflammatory, and Multidrug Resistance Modulation Activity of Silychristin Derivatives

by Jitka Viktorová, Simona Dobiasová, Kateřina Řehořová, David Biedermann, Kristýna Káňová, Karolína Šeborová, Radka Václavíková, Kateřina Valentová, Tomáš Ruml, Vladimír Křen and Tomáš Macek

Antioxidants 2019, 8(8), 303; https://doi.org/10.3390/antiox8080303 - 14 Aug 2019

Cited by 24 | Viewed by 5185

Abstract

Silychristin A is the second most abundant compound of silymarin. Silymarin complex was previously described as an antioxidant with multidrug resistance modulation activity. Here, the results of a classical biochemical antioxidant assay (ORAC) were compared with a cellular assay evaluating the antioxidant capacity [...] Read more.

Silychristin A is the second most abundant compound of silymarin. Silymarin complex was previously described as an antioxidant with multidrug resistance modulation activity. Here, the results of a classical biochemical antioxidant assay (ORAC) were compared with a cellular assay evaluating the antioxidant capacity of pure silychristin A and its derivatives (anhydrosilychristin, isosilychristin and 2,3-dehydrosilychristin A). All the tested compounds acted as antioxidants within the cells, but 2,3-dehydro- and anhydro derivatives were almost twice as potent as the other tested compounds. Similar results were obtained in LPS-stimulated macrophages, where 2,3-dehydro- and anhydrosilychristin inhibited NO production nearly twice as efficiently as silychristin A. The inhibition of P-glycoprotein (P-gp) was determined in vitro, and the respective sensitization of doxorubicin-resistant ovarian carcinoma overproducing P-gp was detected. Despite the fact that the inhibition of P-gp was demonstrated in a concentration-dependent manner for each tested compound, the sensitization of the resistant cell line was observed predominantly for silychristin A and 2,3-dehydrosilychristin A. However, anhydrosilychristin and isosilychristin affected the expression of both the P-gp (ABCB1) and ABCG2 genes. This is the first report showing that silychristin A and its 2,3-dehydro-derivative modulate multidrug resistance by the direct inhibition of P-gp, in contrast to anhydrosilychristin and isosilychristin modulating multidrug resistance by downregulating the expression of the dominant transmembrane efflux pumps. Full article

(This article belongs to the Special Issue Antioxidant and Cytoprotective Activity)

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37 pages, 497 KiB

Open AccessReview

Health Benefits of Nut Consumption in Middle-Aged and Elderly Population

by Marius Emil Rusu, Andrei Mocan, Isabel C. F. R. Ferreira and Daniela-Saveta Popa

Antioxidants 2019, 8(8), 302; https://doi.org/10.3390/antiox8080302 - 12 Aug 2019

Cited by 39 | Viewed by 13696

Abstract

Aging is considered the major risk factor for most chronic disorders. Oxidative stress and chronic inflammation are two major contributors for cellular senescence, downregulation of stress response pathways with a decrease of protective cellular activity and accumulation of cellular damage, leading in time [...] Read more.

Aging is considered the major risk factor for most chronic disorders. Oxidative stress and chronic inflammation are two major contributors for cellular senescence, downregulation of stress response pathways with a decrease of protective cellular activity and accumulation of cellular damage, leading in time to age-related diseases. This review investigated the most recent clinical trials and cohort studies published in the last ten years, which presented the influence of tree nut and peanut antioxidant diets in preventing or delaying age-related diseases in middle-aged and elderly subjects (≥55 years old). Tree nut and peanut ingestion has the possibility to influence blood lipid count, biochemical and anthropometric parameters, endothelial function and inflammatory biomarkers, thereby positively affecting cardiometabolic morbidity and mortality, cancers, and cognitive disorders, mainly through the nuts’ healthy lipid profile and antioxidant and anti-inflammatory mechanisms of actions. Clinical evidence and scientific findings demonstrate the importance of diets characterized by a high intake of nuts and emphasize their potential in preventing age-related diseases, validating the addition of tree nuts and peanuts in the diet of older adults. Therefore, increased consumption of bioactive antioxidant compounds from nuts clearly impacts many risk factors related to aging and can extend health span and lifespan. Full article

(This article belongs to the Special Issue Antioxidant Properties of Natural Products: A Themed Issue in Honor of Professor Isabel C.F.R. Ferreira)

15 pages, 3668 KiB

Open AccessArticle

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 30 | Viewed by 5543

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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14 pages, 4003 KiB

Open AccessArticle

Chemistry and Pharmacology of the Kazakh Crataegus Almaatensis Pojark: An Asian Herbal Medicine

by Sabrina S. Soares, Elmira Bekbolatova, Maria Dulce Cotrim, Zuriyadda Sakipova, Liliya Ibragimova, Wirginia Kukula-Koch, Thais B. Sardella Giorno, Patrícia D. Fernandes, Diogo André Fonseca and Fabio Boylan

Antioxidants 2019, 8(8), 300; https://doi.org/10.3390/antiox8080300 - 10 Aug 2019

Cited by 8 | Viewed by 4201

Abstract

Crataegus almaatensis, an endemic ornamental plant in Kazakhstan is used in popular medicine due to its cardiotonic properties. The most studied species of the same genus are commonly found in Europe, which shows the importance of having the Kazakh species validated via [...] Read more.

Crataegus almaatensis, an endemic ornamental plant in Kazakhstan is used in popular medicine due to its cardiotonic properties. The most studied species of the same genus are commonly found in Europe, which shows the importance of having the Kazakh species validated via its chemical and pharmacological studies. High-speed countercurrent chromatography (HSCCC) operated under optimized conditions enabled an isolation of the three main compounds from the aqueous phase of the leaves ethanol extract, further identified by nuclear magnetic resonance (NMR), as quercetin 3-O-rhamnoside (quercitrin) (4.02% of the crude extract-CECa); quercetin 3-O-β-galactoside (hyperoside) (1.82% of CECa); kaempferol 3-O-α-L-rhamnoside (afzelin) (0.94% of CECa). The CECa, the aqueous phase of the crude extract (APCa) together with the isolates were evaluated for their vascular (vascular reactivity in human internal mammary artery-HIMA), anti-nociceptive (formalin-induced liking response and hot plate) and anti-inflammatory (subcutaneous air-pouch model-SAP) activities. CECa at the concentrations of 0.014 and 0.14 mg/mL significantly increased the maximum contractility response of HIMA to noradrenaline. The APCa CR curve (0.007–0.7 mg/mL) showed an intrinsic relaxation effect of the HIMA. APCa at the dose of 100 mg/kg i.p. significantly decreased the total leukocyte count and the IL-1β release in the SAP wash. Full article

(This article belongs to the Special Issue Antioxidant and Anti-inflammatory Properties of Plants Extract)

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13 pages, 1369 KiB

Open AccessArticle

Antioxidant and Potentially Anti-Inflammatory Activity of Anthocyanin Fractions from Pomace Obtained from Enzymatically Treated Raspberries

by Urszula Szymanowska and Barbara Baraniak

Antioxidants 2019, 8(8), 299; https://doi.org/10.3390/antiox8080299 - 10 Aug 2019

Cited by 56 | Viewed by 4740

Abstract

Raspberry pomace was obtained from raspberries subjected to enzymatic maceration using three commercial pectinolytic preparations (Pectinex Ultra SP-L, Pectinex Yield Mash, and Ultrazym AFP-L). Phenolic compounds were extracted and anthocyanin fractions were isolated using the SPE solid phase extraction technique. In the separated [...] Read more.

Raspberry pomace was obtained from raspberries subjected to enzymatic maceration using three commercial pectinolytic preparations (Pectinex Ultra SP-L, Pectinex Yield Mash, and Ultrazym AFP-L). Phenolic compounds were extracted and anthocyanin fractions were isolated using the SPE solid phase extraction technique. In the separated anthocyanin fractions, the content of individual compounds was determined by the HPLC technique and the antioxidant activity was assessed with four complementary methods (DPPH and ABTS radical scavenging activity, chelating Fe(II) power, and ferric reducing power). Potential anti-inflammatory properties were also identified as the ability to inhibit the activity of lipoxygenase and cyclooxygenase 2. For these enzymes, the type of inhibition was determined based on the Lineweaver–Burke plot. Full article

(This article belongs to the Special Issue Extraction of Antioxidants from Food Waste)

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15 pages, 6186 KiB

Open AccessArticle

Characterization and Antioxidant Activities of Yellow Strain Flammulina velutipes (Jinhua Mushroom) Polysaccharides and Their Effects on ROS Content in L929 Cell

by Yu-Ning Hu, Tzu-Jung Sung, Chun-Hsu Chou, Kai-Lun Liu, Liang-Po Hsieh and Chang-Wei Hsieh

Antioxidants 2019, 8(8), 298; https://doi.org/10.3390/antiox8080298 - 10 Aug 2019

Cited by 48 | Viewed by 4867

Abstract

Yellow strain Flammulina velutipes, which is known as Jinhua mushroom in Taiwan, has become popular among customers due to its distinct texture that is utterly different from white strain F. velutipes. However, there has been little study on the physicochemical properties, [...] Read more.

Yellow strain Flammulina velutipes, which is known as Jinhua mushroom in Taiwan, has become popular among customers due to its distinct texture that is utterly different from white strain F. velutipes. However, there has been little study on the physicochemical properties, antioxidant activities, and biological functions of yellow strain F. velutipes polysaccharides (FVYs). The specific aims of this study are to evaluate and compare the physicochemical properties, antioxidant activities, and biological functions of FVYs and white strain F. velutipes polysaccharides (FVWs) in order to select the strain appropriate for cosmetic ingredient. The FVYs and FVWs were prepared by fractional precipitation (40%, 60%, and 80%). According to the results, FVY-80 showed the greatest antioxidant activities based on 2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC₅₀ = 2.22 mg/mL) and 2,2’ -azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical assay (IC₅₀ = 2.04 mg/mL). None of the fractions exhibited cytotoxicity toward L929 cell under a concentration of 500

μ

g/mL. FVY-80 significantly reduced the reactive oxygen species (ROS) content in L929 cell by 55.96%, as compared with the H₂O₂-induced L929 cell, according to the dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay. In conclusion, we suggest that FVY-80 is the best source for a cosmetics ingredient. Full article

(This article belongs to the Section Natural and Synthetic Antioxidants)

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8 pages, 804 KiB

Open AccessProject Report

Antioxidants: Terminology, Methods, and Future Considerations

by Khiena Brainina, Natalia Stozhko and Marina Vidrevich

Antioxidants 2019, 8(8), 297; https://doi.org/10.3390/antiox8080297 - 09 Aug 2019

Cited by 47 | Viewed by 6257

Abstract

Unreliable terminology and incompatible units of antioxidant activity/concentration expression lead to the failure of antioxidant clinical trials, ambiguity of conclusions about the effect of a chosen therapy in medicine and evaluation of food quality, diet, difficulties using information in monitoring the training process [...] Read more.

Unreliable terminology and incompatible units of antioxidant activity/concentration expression lead to the failure of antioxidant clinical trials, ambiguity of conclusions about the effect of a chosen therapy in medicine and evaluation of food quality, diet, difficulties using information in monitoring the training process in sports, etc. Many different terms (antiradical activity, antioxidant activity, antioxidant capacity, antioxidant power, antioxidant ability) and methods: Trolox equivalent capacity assay (TEAC), Ferric Reducing Antioxidant Power assay (FRAP), Cupric Reducing Antioxidant Capacity assay (CUPRAC), antioxidative activity assay (ABTS), the oxygen radical absorbance capacity (ORAC), and different options of electrochemical ones) proposed for the determination of antioxidants are described. Possible approaches to the development of this field of science and practice are considered. Full article

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12 pages, 1201 KiB

Open AccessArticle

Antioxidant and Anti-Inflammatory Activities of the Crude Extracts of Moringa oleifera from Kenya and Their Correlations with Flavonoids

by Yong-Bing Xu, Gui-Lin Chen and Ming-Quan Guo

Antioxidants 2019, 8(8), 296; https://doi.org/10.3390/antiox8080296 - 09 Aug 2019

Cited by 117 | Viewed by 8065

Abstract

Moringa oleifera Lam. (M. oleifera) is commonly distributed and utilized in tropical and sub-tropical areas. There has been a large number of reports on the antioxidant and anti-inflammatory activity of its leaves, but only a few about its seeds and roots. [...] Read more.

Moringa oleifera Lam. (M. oleifera) is commonly distributed and utilized in tropical and sub-tropical areas. There has been a large number of reports on the antioxidant and anti-inflammatory activity of its leaves, but only a few about its seeds and roots. Hence, in this work we aimed to systematically compare the antioxidant and anti-inflammatory activities of the ethanol crude extracts of leaves, seeds, and roots of M. oleifera from Kenya, and further correlate the differential activities with the chemical constituents from these three parts. The antioxidant activities were measured by using three different assays (DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2′-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) and FRAP (Ferric-Reducing Antioxidant Power), respectively). Results showed that the leaf extracts displayed the highest DPPH radical scavenging and FRAP total reducing power activities with IC₅₀ values of 1.02 ± 0.13 mg/mL and 0.99 ± 0.06 mM Fe²⁺/g, respectively; the leaf and root extracts exhibited potential ABTS radical scavenging activities with the IC₅₀ values of 1.36 ± 0.02 and 1.24 ± 0.03 mg/mL. Meanwhile, the leaf and seed extracts (11.1–100 µg/mL) also exerted obvious anti-inflammatory activities, as indicated by the inhibition of NO production. To further reveal correlations between these differential activities with the chemical constituents in the three organs, the total flavonoids content (TFC) of the three different extracts were evaluated, and the TFC of leaves, seeds and roots were found to be 192.36 ± 2.96, 5.89 ± 0.65 and 106.79 ± 2.12 mg rutin equivalent (RE)/g, respectively. These findings indicated the important impacts of the total flavonoid contents on antioxidant and anti-inflammatory activities. Additionally, we further determined the phytochemical profiles of M. oleifera by HPLC-UV/ESI-MS/MS, and identified most of the chemical constituents of leaves as flavonoids. In summary, the leaves of M. oleifera are a better potential natural source of antioxidants and anti-inflammatory agents, and very promising for development into the health promoting dietary supplements. Full article

(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)

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Antioxidants, Volume 8, Issue 8 (August 2019) – 88 articles

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