Antioxidants

1571 KiB

Open AccessReview

Mycosporine-Like Amino Acids and Their Derivatives as Natural Antioxidants

by Naoki Wada, Toshio Sakamoto and Seiichi Matsugo

Antioxidants 2015, 4(3), 603-646; https://doi.org/10.3390/antiox4030603 - 7 Sep 2015

Cited by 199 | Viewed by 19449

Mycosporine-like amino acids (MAAs) are water-soluble molecules that absorb UV-A and UV-B radiation and disperse the energy as heat. MAAs show great diversity in their molecular structures, which exhibit a range of molecular weights spanning 188 to 1050 Daltons. MAAs are utilized in [...] Read more.

Mycosporine-like amino acids (MAAs) are water-soluble molecules that absorb UV-A and UV-B radiation and disperse the energy as heat. MAAs show great diversity in their molecular structures, which exhibit a range of molecular weights spanning 188 to 1050 Daltons. MAAs are utilized in a wide variety of organisms including prokaryotes and eukaryotic micro-organisms that inhabit aquatic, terrestrial, and marine environments. These features suggest that MAAs are stable and fundamental molecules that allow these organisms to live under UV irradiation. MAAs are thought to have been greatly important to ancient forms of life on Earth, functioning as a primary sunscreen to reduce short-wavelength light. Structurally different MAAs might have been developed in MAA-producing organisms during their environmental adaptation. Harmful irradiation directly damages biomolecules, including lipids, proteins and DNA, and induces oxidative stress through radical-propagating processes. Thus, MAAs are expected to play an additional role in the antioxidant system. This review focuses on MAAs with radical scavenging activities. To cover all the reported MAAs known thus far, we surveyed the CAS database and have summarized the structures and the chemical and physical properties of these MAAs, including their antioxidant activities. Full article

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430 KiB

Open AccessArticle

Amazonian Native Palm Fruits as Sources of Antioxidant Bioactive Compounds

by Mary De Fátima Guedes Dos Santos, Rosa Virginia Soares Mamede, Maria Do Socorro Moura Rufino, Edy Sousa De Brito and Ricardo Elesbão Alves

Antioxidants 2015, 4(3), 591-602; https://doi.org/10.3390/antiox4030591 - 7 Sep 2015

Cited by 59 | Viewed by 8749

Abstract

The Amazon region has many sources of fruits, especially native ones not yet explored, but which have some potential for use, as is the case with certain palms. The objective of this study was to evaluate the content of bioactive compounds and total [...] Read more.

The Amazon region has many sources of fruits, especially native ones not yet explored, but which have some potential for use, as is the case with certain palms. The objective of this study was to evaluate the content of bioactive compounds and total antioxidant capacities of fruits from native palms from the Brazilian Amazon. The fruits of five palm species (bacaba, buriti, inajá, pupunha, and tucumã) were evaluated for levels of ascorbic acid, anthocyanins, yellow flavonoids, total carotenoids, and total extractable polyphenols, as well as the total antioxidant capacities. The fruits had high contents of extractable total polyphenols, especially bacaba and tucumã (941.56 and 158.98 mg of galic acid·100g⁻¹), total carotenoids in the case of tucumã and buriti (7.24 and 4.67 mg·100g⁻¹), and anthocyanins in bacaba (80.76 mg·100g⁻¹). As for the antioxidant capacity, bacaba had the highest total antioxidant activity by the Oxygen Radical Antioxidant Capacity (ORAC) (194.67 µM·Trolox·g⁻¹), 2,2-diphenyl-1-picrylhydrazyl (DPPH) (47.46 g·pulp·g⁻¹ DPPH), and β-carotene/linoleic acid (92.17% Oxidation Inhibition (O.I) methods. Bacaba phenolic profile revealed the presence of cyanidin-3-O-rutinoside and other flavonoids. The palm fruits studied can be considered good sources of bioactive compounds, some containing higher amounts than that of commonly consumed fruits. Total extractable polyphenols and anthocyanins were directly correlated to antioxidant activity in these fruits. Full article

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Open AccessReview

Periodontal Disease-Induced Atherosclerosis and Oxidative Stress

by Tomoko Kurita-Ochiai, Ru Jia, Yu Cai, Yohei Yamaguchi and Masafumi Yamamoto

Antioxidants 2015, 4(3), 577-590; https://doi.org/10.3390/antiox4030577 - 2 Sep 2015

Cited by 34 | Viewed by 8597

Abstract

Periodontal disease is a highly prevalent disorder affecting up to 80% of the global population. Recent epidemiological studies have shown an association between periodontal disease and cardiovascular disease, as oxidative stress plays an important role in chronic inflammatory diseases such as periodontal disease [...] Read more.

Periodontal disease is a highly prevalent disorder affecting up to 80% of the global population. Recent epidemiological studies have shown an association between periodontal disease and cardiovascular disease, as oxidative stress plays an important role in chronic inflammatory diseases such as periodontal disease and cardiovascular disease. In this review, we focus on the mechanisms by which periodontopathic bacteria cause chronic inflammation through the enhancement of oxidative stress and accelerate cardiovascular disease. Furthermore, we comment on the antioxidative activity of catechin in atherosclerosis accelerated by periodontitis. Full article

(This article belongs to the Special Issue Antioxidants and Periodontal Diseases)

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Open AccessArticle

Determination of Phenolic Content in Different Barley Varieties and Corresponding Malts by Liquid Chromatography-diode Array Detection-Electrospray Ionization Tandem Mass Spectrometry

by Daniel O. Carvalho, Andreia F. Curto and Luís F. Guido

Antioxidants 2015, 4(3), 563-576; https://doi.org/10.3390/antiox4030563 - 14 Aug 2015

Cited by 72 | Viewed by 8930

Abstract

A simple and reliable method for the simultaneous determination of nine phenolic compounds in barley and malted barley was established, using liquid chromatography-diode array detection-electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS/MS). The phenolic compounds can be easily detected with both systems, despite significant differences [...] Read more.

A simple and reliable method for the simultaneous determination of nine phenolic compounds in barley and malted barley was established, using liquid chromatography-diode array detection-electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS/MS). The phenolic compounds can be easily detected with both systems, despite significant differences in sensitivity. Concentrations approximately 180-fold lower could be achieved by mass spectrometry analysis compared to diode array detection, especially for the flavan-3-ols (+)-catechin and (−)-epicatechin, which have poor absorptivity in the UV region. Malt samples were characterized by higher phenolic content comparing to corresponding barley varieties, revealing a significant increase of the levels of (+)-catechin and (−)-epicatechin during the malting process. Moreover, the industrial malting is responsible for modification on the phenolic profile from barley to malt, namely on the synthesis or release of sinapinic acid and epicatechin. Accordingly, the selection of the malting parameters, as well as the barley variety plays an important role when considering the quality and antioxidant stability of beer. Full article

(This article belongs to the Special Issue Analytical Determination of Polyphenols)

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Open AccessArticle

Extraction, Separation, and Identification of Phenolic Compounds in Virgin Olive Oil by HPLC-DAD and HPLC-MS

by Maria Tasioula-Margari and Eleftheria Tsabolatidou

Antioxidants 2015, 4(3), 548-562; https://doi.org/10.3390/antiox4030548 - 13 Aug 2015

Cited by 84 | Viewed by 14281

Abstract

The aim of this study was to evaluate the recovery of individual phenolic compounds extracted from virgin olive oil (VOO), from different Greek olive varieties. Sufficient recoveries (90%) of all individual phenolic compounds were obtained using methanol as an extraction solvent, acetonitrile for [...] Read more.

The aim of this study was to evaluate the recovery of individual phenolic compounds extracted from virgin olive oil (VOO), from different Greek olive varieties. Sufficient recoveries (90%) of all individual phenolic compounds were obtained using methanol as an extraction solvent, acetonitrile for residue solubilization, and two washing steps with hexane. Moreover, in order to elucidate structural characteristics of phenolic compounds in VOO, high performance liquid chromatography with a diode array detector (HPLC-DAD) at 280 and 340 nm and HPLC coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS) in the negative-ion mode were performed. The most abundant phenolic compounds were oleuropein derivatives with m/z 319 and 377 and ligstroside derivatives with m/z 303, 361. Lignans, such as 1-acetoxypinoresinol and pinoresinol were also present in substantial quantities in the phenolic fraction. However, pinoresinol was co-eluted with dialdehydic form of ligstroside aglycone (DAFLA) and it was not possible to be quantified separately. The phenolic extracts, obtained from different VOO samples, yielded similar HPLC profiles. Differences, however, were observed in the last part of the chromatogram, corresponding to isomers of the aldehydic form of ligstroside aglycone. Oxidized phenolic products, originating from secoiridoids, were also detected. Full article

(This article belongs to the Special Issue Analytical Determination of Polyphenols)

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839 KiB

Open AccessArticle

Development of Biocomposites with Antioxidant Activity Based on Red Onion Extract and Acetate Cellulose

by Carol López De Dicastillo, Rosa Navarro, Abel Guarda and Maria José Galotto

Antioxidants 2015, 4(3), 533-547; https://doi.org/10.3390/antiox4030533 - 3 Aug 2015

Cited by 29 | Viewed by 7630

Abstract

Antioxidant biocomposites have been successfully developed from cellulose acetate, eco-friendly triethyl citrate plasticizer and onion extract as a source of natural antioxidants. First, an onion extraction process was optimized to obtain the extract with highest antioxidant power. Extracts under absolute ethanol and ethanol [...] Read more.

Antioxidant biocomposites have been successfully developed from cellulose acetate, eco-friendly triethyl citrate plasticizer and onion extract as a source of natural antioxidants. First, an onion extraction process was optimized to obtain the extract with highest antioxidant power. Extracts under absolute ethanol and ethanol 85% were the extracts with the highest antioxidant activity, which were the characterized through different methods, DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2ʹ-azinobis(3-ethylbenzothiazoline-6-sulphonate)), that measure radical scavenger activity, and polyphenolic and flavonoid content. Afterwards, the extract was incorporated in cellulose acetate as polymer matrix owing to develop an active material intended to oxidative sensitive food products packaging. Different concentrations of onion extract and plasticizer were statistically studied by using response surface methodology in order to analyze the influence of both factors on the release of active compounds and therefore the antioxidant activity of these materials. Full article

(This article belongs to the Special Issue Analytical Determination of Polyphenols)

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395 KiB

Open AccessCommunication

Qualitative Study of Functional Groups and Antioxidant Properties of Soy-Based Beverages Compared to Cow Milk

by Alessandra Durazzo, Paolo Gabrielli and Pamela Manzi

Antioxidants 2015, 4(3), 523-532; https://doi.org/10.3390/antiox4030523 - 15 Jul 2015

Cited by 23 | Viewed by 10436

Abstract

Soy-based beverages are a source of high quality proteins and balanced nutrients; they thus represent an alternative to milk in case of allergy to cow milk proteins or intolerance to lactose. In this research, antioxidant properties of soy-based beverages and UHT cow milk [...] Read more.

Soy-based beverages are a source of high quality proteins and balanced nutrients; they thus represent an alternative to milk in case of allergy to cow milk proteins or intolerance to lactose. In this research, antioxidant properties of soy-based beverages and UHT cow milk were studied. In addition, color parameters, by a quick and non-destructive methodology, were studied in order to verify a possible correlation with antioxidant properties and a qualitative analysis of the major functional groups undertaken by Fourier Transformed Infrared Spectroscopy (FTIR) on Attenuated Total Reflectance (ATR) was carried out. Extractable and hydrolysable polyphenols were studied in soy-based beverages. However, only the extractable fraction was studied in UHT milk, which was characterized by a small amount of polyphenols. All color parameters showed highly significant differences among soy-based beverages and between soy-based beverages and cow milk. FTIR-ATR spectra of soy-based beverages and cow milk showed several differences in the various regions depending on both the specific contribution of molecular groups and different food items. Full article

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426 KiB

Open AccessArticle

Drinking Hydrogen-Rich Water Has Additive Effects on Non-Surgical Periodontal Treatment of Improving Periodontitis: A Pilot Study

by Tetsuji Azuma, Mayu Yamane, Daisuke Ekuni, Yuya Kawabata, Kota Kataoka, Kenta Kasuyama, Takayuki Maruyama, Takaaki Tomofuji and Manabu Morita

Antioxidants 2015, 4(3), 513-522; https://doi.org/10.3390/antiox4030513 - 9 Jul 2015

Cited by 10 | Viewed by 9718

Abstract

Oxidative stress is involved in the pathogenesis of periodontitis. A reduction of oxidative stress by drinking hydrogen-rich water (HW) might be beneficial to periodontal health. In this pilot study, we compared the effects of non-surgical periodontal treatment with or without drinking HW on [...] Read more.

Oxidative stress is involved in the pathogenesis of periodontitis. A reduction of oxidative stress by drinking hydrogen-rich water (HW) might be beneficial to periodontal health. In this pilot study, we compared the effects of non-surgical periodontal treatment with or without drinking HW on periodontitis. Thirteen patients (3 women, 10 men) with periodontitis were divided into two groups: The control group (n = 6) or the HW group (n = 7). In the HW group, participants consumed HW 4–5 times/day for eight weeks. At two to four weeks, all participants received non-surgical periodontal treatment. Oral examinations were performed at baseline, two, four and eight weeks, and serum was obtained at these time points to evaluate oxidative stress. At baseline, there were no significant differences in periodontal status between the control and HW groups. The HW group showed greater improvements in probing pocket depth and clinical attachment level than the control group at two, four and eight weeks (p < 0.05). The HW group also exhibited an increased serum level of total antioxidant capacity at four weeks, compared to baseline (p < 0.05). Drinking HW enhanced the effects of non-surgical periodontal treatment, thus improving periodontitis. Full article

(This article belongs to the Special Issue Antioxidants and Periodontal Diseases)

503 KiB

Open AccessArticle

HPLC-DAD Phenolic Characterization and Antioxidant Activities of Ripe and Unripe Sweet Orange Peels

by Olufunmilayo Sade Omoba, Rebeccah Olajumoke Obafaye, Sule Ola Salawu, Aline Augusti Boligon and Margareth Linde Athayde

Antioxidants 2015, 4(3), 498-512; https://doi.org/10.3390/antiox4030498 - 9 Jul 2015

Cited by 73 | Viewed by 9223

Abstract

Phenolic compounds of unripe and ripe sweet orange peels were determined using a high-performance liquid chromatography separation method with diode array detector (HPLC-DAD). The in vitro antioxidant properties and the EC₅₀ (concentration required to obtain a 50% antioxidant effect) values were also [...] Read more.

Phenolic compounds of unripe and ripe sweet orange peels were determined using a high-performance liquid chromatography separation method with diode array detector (HPLC-DAD). The in vitro antioxidant properties and the EC₅₀ (concentration required to obtain a 50% antioxidant effect) values were also determined. The predominant phenolic compounds were quercitrin, rutin, and quercetin with values of 18.77 ± 0.01 mg/mL, 18.65 ± 0.03 mg/mL, and 10.39 ± 0.01 mg/mL respectively in unripe orange peel and 22.61 ± 0.01 mg/mL, 17.93 ± 0.03 mg/mL, and 14.03 ± 0.02 mg/mL respectively in ripe orange peel. The antioxidant properties revealed 2,2′-azino-bis(3-ethyl benzothiazoline-6-sulfonic acid) diammonium salt (ABTS) scavenging ability of both unripe and ripe orange peels respectively as 14.68 ± 0.01 and 16.89 ± 0.02 mmol TEAC/g, the Ferric Reducing Antioxidant Properties (FRAP) as 70.69 ± 0.01 and 91.38 ± 0.01 mg gallic acid equivalents/100g, total phenol content as 5.27 ± 0.03 and 9.40 ± 0.01 mg gallic acid equivalents/g and total flavonoid content as 3.30 ± 0.30 and 4.20 ± 0.02 mg quercetin equivalent/g. The antioxidant assays showed enhanced potency of extract from ripe orange peel with EC50 values of 2.71 ± 0.03 mg/mL for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 0.67 ± 0.03 mg/mL for hydroxyl radicals (OH*), 0.57 ± 0.02 mg/mL for Fe²⁺ chelation, and 0.63 ± 0.06 mg/mL for malondialdehyde (MDA), and was more potent than unripe orange peel. Full article

(This article belongs to the Special Issue Analytical Determination of Polyphenols)

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402 KiB

Open AccessReview

Infrared Spectroscopy as a Versatile Analytical Tool for the Quantitative Determination of Antioxidants in Agricultural Products, Foods and Plants

by Daniel Cozzolino

Antioxidants 2015, 4(3), 482-497; https://doi.org/10.3390/antiox4030482 - 2 Jul 2015

Cited by 70 | Viewed by 9116

Abstract

Spectroscopic methods provide with very useful qualitative and quantitative information about the biochemistry and chemistry of antioxidants. Near infrared (NIR) and mid infrared (MIR) spectroscopy are considered as powerful, fast, accurate and non-destructive analytical tools that can be considered as a replacement of [...] Read more.

Spectroscopic methods provide with very useful qualitative and quantitative information about the biochemistry and chemistry of antioxidants. Near infrared (NIR) and mid infrared (MIR) spectroscopy are considered as powerful, fast, accurate and non-destructive analytical tools that can be considered as a replacement of traditional chemical analysis. In recent years, several reports can be found in the literature demonstrating the usefulness of these methods in the analysis of antioxidants in different organic matrices. This article reviews recent applications of infrared (NIR and MIR) spectroscopy in the analysis of antioxidant compounds in a wide range of samples such as agricultural products, foods and plants. Full article

(This article belongs to the Special Issue Analytical Determination of Polyphenols)

794 KiB

Open AccessReview

Non-Nutrient, Naturally Occurring Phenolic Compounds with Antioxidant Activity for the Prevention and Treatment of Periodontal Diseases

by Alfonso Varela-López, Pedro Bullón, Francesca Giampieri and José L. Quiles

Antioxidants 2015, 4(3), 447-481; https://doi.org/10.3390/antiox4030447 - 24 Jun 2015

Cited by 37 | Viewed by 9716

Abstract

One of the main factors able to explain the pathophysiological mechanism of inflammatory conditions that occur in periodontal disease is oxidative stress. Given the emerging understanding of this relationship, host-modulatory therapies using antioxidants could be interesting to prevent or slow the breakdown of [...] Read more.

One of the main factors able to explain the pathophysiological mechanism of inflammatory conditions that occur in periodontal disease is oxidative stress. Given the emerging understanding of this relationship, host-modulatory therapies using antioxidants could be interesting to prevent or slow the breakdown of soft and hard periodontal tissues. In this context, non-nutrient phenolic compounds of various foods and plants have received considerable attention in the last decade. Here, studies focusing on the relationship between different compounds of this type with periodontal disease have been collected. Among them, thymoquinone, coenzyme Q (CoQ), mangiferin, resveratrol, verbascoside and some flavonoids have shown to prevent or ameliorate periodontal tissues damage in animal models. However evidence regarding this effect in humans is poor and only limited to topical treatments with CoQ and catechins. Along with animal experiments, in vitro studies indicate that possible mechanisms by which these compounds might exert their protective effects include antioxidative properties, oxygen and nitrogen scavenging abilities, and also inhibitory effects on cell signaling cascades related to inflammatory processes which have an effect on RNS or ROS production as well as on antioxidant defense systems. Full article

(This article belongs to the Special Issue Antioxidants and Periodontal Diseases)

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Antioxidants, Volume 4, Issue 3 (September 2015) – 11 articles , Pages 447-646

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