scholarly journals Aromatic Plants: Antioxidant Capacity and Polyphenol Characterisation

2017 ◽  
Author(s):  
Charalampos Proestos ◽  
Theo Varzakas
Keyword(s):  
Free Radical ◽  
Antioxidant Capacity ◽  
Radical Scavenging Activity ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Aromatic Plants ◽  
Polyphenol Content ◽  
Stable Free Radical ◽  
Rancimat Test ◽  
Phenolic Substances

The antioxidant properties and polyphenol content of some selected aromatic plants grown in Greece were studied. Plants were refluxed with 60% methanol after acid hydrolysis. The phenolic substances were quantified by HPLC-DAD. The antioxidant capacity of the extracts was determined with the Rancimat test using sunflower oil as substrate. Free radical scavenging activity was measured using the stable free radical 1, 1-diphenyl-2-picrylhydrazyl (DPPH). Results were compared with standard BHT and ascorbic acid. Total phenol concentration of the extracts was estimated with Folin-Ciocalteu reagent using gallic acid as standard.

Comparison of Antioxidant Effects of the Proton Pump-Inhibiting Drugs Omeprazole, Esomeprazole, Lansoprazole, Pantoprazole, and Rabeprazole

Pharmacology ◽  
2020 ◽  
Vol 105 (11-12) ◽  
pp. 645-651 ◽  
Author(s):  
Mohammed N. Abed ◽  
Fawaz A. Alassaf ◽  
Mahmood H.M. Jasim ◽  
Mohanad Alfahad ◽  
Mohannad E. Qazzaz
Keyword(s):  
Free Radical ◽  
Proton Pump ◽  
Radical Scavenging Activity ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Acid Suppression ◽  
Free Radical Scavenging Activity ◽  
Scavenging Activity ◽  
Stable Free Radical

<b><i>Introduction:</i></b> Peptic lesions usually develop when there is an imbalance between aggressive drivers and gastro-protective mediators that guard the lining of the gastrointestinal tract. The most crucial of these mediators are antioxidants, whose loss may predispose to oxidative stress, which is believed to be the main aggravator of several diseases including peptic ulcer. Proton pump inhibitors (PPIs) are drugs that are highly effective and widely used for therapeutic management of peptic disorders through inhibition of gastric acid secretion. In spite of this, oxidative damage may continue to be a major issue that can predispose to future lesions. <b><i>Objective:</i></b> The present study is designed to explore the possible antioxidant capability of different PPIs, including omeprazole, esomeprazole, lansoprazole, pantoprazole, and rabeprazole, in an aim to suggest an agent that, in addition to its acid-suppression properties, can provide antioxidant profit. <b><i>Methods:</i></b> The antioxidant activity of different PPIs was evaluated calorimetrically to test the ability of each drug to quench oxygen free radical, using the well-known stable free radical α,α-diphenyl-β-picrylhydrazyl (DPPH), and compared to ascorbic acid (AA; vitamin C). The measurements were performed using a spectrophotometer at 517 nm. <b><i>Results:</i></b> All the studied drugs reduced DPPH, but to different extents. However, omeprazole and esomeprazole showed the highest ability to scavenge free radicals (50% inhibitory concentrations [IC<sub>50</sub>s] of the percentage for free radical scavenging activity are 18.7 ± 5.7 and 18.7 ± 5.7, respectively, and the AA equivalents are 83,772 ± 11,887 and 81,732 ± 8,523 mg AA/100 g, respectively). Conversely, lansoprazole, pantoprazole, and rabeprazole might be having no role in this story (IC<sub>50</sub>s of the percentage for free radical scavenging activity are 49.3 ± 3.1, 49 ± 9.4, and 40.7 ± 7.2, respectively, and the AA equivalents are 30,458 ± 3,884, 32,222 ± 10,377, and 37,876 ± 8,816 mg AA/100 g, respectively). <b><i>Conclusion:</i></b> Thus, omeprazole and esomeprazole may confer a significant dual action in gastrointestinal protection by providing potent antioxidant properties in addition to their major role as acid-suppression agents. However, further studies are essential to elucidate the mechanism behind the difference between the drugs of the same class.

Strong antihemolytic and antioxidant properties of aqueous extract from Algerian Hammada elegans (Bge.) Botsch (Chenopodiaceae)

2021 ◽  
Vol 17 ◽  
Author(s):  
Brahim Asseli ◽  
Reguia Mahfoudi ◽  
Amar Djeridane ◽  
Mohamed Yousfi
Keyword(s):  
Free Radical ◽  
Aqueous Extract ◽  
Radical Scavenging Activity ◽  
Condensed Tannin ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Total Phenolic ◽  
Dependent Manner ◽  
Vitro Assay

Background: Research on medicinal plant antioxidants has emerged as a potential therapeutic to prevent free radical generated damage in the human body. Hammada elegans Botsch (popularly known as “Ajram”) is a xerophytic plant widely found in Laghouat region, but there are only a few reports about the biological or chemical properties of these species. Hence, the aim of this study is to investigate the antioxidant and the antihemolytic activities of hexanic, acetonic, methanolic and aqueous extracts of aerial parts of Algerian Hammada elegans Botsch by employing different in vitro assay systems. Methods: The total phenolic content, the flavonoid content and the condensed tannin amount were analyzed using Folin-Ciocalteu, aluminum chloride and vanillin assays, respectively. The in vitro antioxidant capacity of extracts was assessed by CUPRAC, iron chelating, ABTS•+and antihemolytic assays, and was expressed as EC50 values. Results: Among the analyzed extracts, the aqueous extract had the highest phenolic, flavonoid and tannin contents. Also, this extract displayed the highest antioxidant capacities compared to the other extracts and standards. Its EC50 value for ABTS radical-scavenging activity was 0.265 ± 0.003 mg/L. Moreover, this extract showed high iron (II) chelating ability (EC50 = 0.958 ± 0.001 mg/L), and good antioxidant activity in the cupric ion reducing activity (CUPRAC) in a concentration dependent manner (EC50 were 0.709 ± 0.002 mg/L). Additionally, this extract had the best antihemolytic activity against AAPH-induced hemolysis (EC50=0.090 ± 0.004 mg/L). Conclusion: Our study revealed that the aqueous extract of Hammada elegans Botsch, is a potential source of antioxidants which possess a high protective effect of membrane against free radical.

scholarly journals ANTIOXIDANT ACTIVITY OF LEAF EXTRACTS OF HEMIDESMUS INDICUS (L.) R.BR. (ASCLEPIADACEAE).

2017 ◽  
Vol 10 (6) ◽  
pp. 200
Author(s):  
Abdul Kaffoor H ◽  
Muthuraj K ◽  
Arumugasamy K
Keyword(s):  
Free Radical ◽  
Aqueous Extract ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Free Radical Scavenging Activity ◽  
Scavenging Activity ◽  
Leaf Extracts ◽  
Stable Free Radical ◽  
Hemidesmus Indicus

Objective: A number of Indian medicinal plants have been used for thousands of years in a traditional system of medicine. Hemidesmus indicus is an important member of the Asclepiadaceae family. It is an endemic to the southern Western Ghats, India. The aim of the study was to investigate the free radical scavenging activity of H. indicus. Methods: The aqueous and methanol leaf extracts of H. indicus were assayed for radical scavenging activity, using the stable free radical 2,2-diphenyl- 1-picryl-hydrazyl-hydrate and 2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid). Results: The results revealed that the IC50 values of aqueous extract of H. indicus were found to be higher than that of the other solvent extracts. The free radical scavenging activity of the plant extracts may be due to the presence of phytoconstituents. Conclusion: In all the methods, the aqueous extract has exhibited the good scavenging activity and this arises that the plant has a potential antioxidant agent.

Contribution of anthocyanins to the antioxidant capacity of juvenile and senescing sugar maple (Acer saccharum) leaves

2007 ◽  
Vol 34 (8) ◽  
pp. 714 ◽  
Author(s):  
Abby K. van den Berg ◽  
Timothy D. Perkins
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Antioxidant Capacity ◽  
Acer Saccharum ◽  
Sugar Maple ◽  
Radical Scavenging ◽  
Anthocyanin Content ◽  
Additional Source ◽  
Stable Free Radical ◽  
Maple Leaves

Foliar anthocyanins are hypothesised to provide an additional source of photoprotection from photooxidative stress to the leaves in which they occur through their ability to scavenge excess free radical species. Although demonstrated to significantly enhance the antioxidant status of red morphs of fully expanded leaves of some species, the contribution of anthocyanins to the antioxidant capacity of the juvenile and senescing leaves in which they frequently occur has not been examined. Antioxidant activity of extracts from anthocyanic and non-anthocyanic juvenile and senescing sugar maple (Acer saccharum Marsh.) leaves from similar light environments was assessed using the stable free radical 1,1-diphenyl-2-picryl hydrazyl (DPPH). Anthocyanin content was significantly correlated with antioxidant activity in extracts of anthocyanic juvenile leaves but only weakly correlated in extracts of anthocyanic senescing leaves. In addition, the antioxidant activity of anthocyanic and non-anthocyanic leaves was equal in both juvenile and senescing leaves. Thus, although anthocyanins may contribute to the antioxidant capacity of anthocyanic juvenile and senescing sugar maple leaves, these results are not consistent with the hypothesis that anthocyanins provide an enhancement to the photoprotection available in either leaf type through free radical scavenging. The results suggest anthocyanins may be part of alternative strategies employed by anthocyanic juvenile and senescing maple leaves to achieve similar levels of antioxidant capacity as their non-anthocyanic counterparts to cope with the same set of environmental challenges.

scholarly journals Antioxidant capacity, phenolic and vitamin C contents of quinoa (Chenopodium quinoa Willd.) as affected by sprouting and storage conditions

2017 ◽  
Vol 12 (1) ◽  
Author(s):  
Maura N. Laus ◽  
Mariagrazia P. Cataldi ◽  
Carlo Robbe ◽  
Tiziana D'Ambrosio ◽  
Maria L. Amodio ◽  
...  
Keyword(s):  
Vitamin C ◽  
Antioxidant Capacity ◽  
Peroxyl Radical ◽  
Radical Scavenging Activity ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Chenopodium Quinoa ◽  
Storage Conditions ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Reducing Activity

Antioxidant capacity (AC) of quinoa (<em>Chenopodium quinoa</em> Willd. cv. Real) seeds and sprouts obtained after 4 days of seed germination at 20°C and 70% humidity was evaluated using trolox equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) assays, able to highlight reducing activity and peroxyl radical scavenging capacity, respectively; phenolic content (PC) was also measured. Both TEAC and ORAC assays revealed a significantly higher (about 2- and 2.8-fold, respectively) AC of 4-day-old sprouts compared to seeds; consistently, also PC values of sprouts resulted about 2.6 times higher than seeds. In order to investigate the influence of storage on AC and PC, as well as on vitamin C content (VCC), 4-day-old sprouts were subjected for 7 days at 5°C to three different conditions of controlled atmosphere storage (CAS) compared with air. Interestingly, whatever the CAS conditions, storage of quinoa sprouts up to 7 days induced an increase of AC evaluated in terms of reducing activity by TEAC assay. Consistently, an increase of PC and VCC was measured during storage, positively correlated to TEAC values. Moreover, a decrease of peroxyl radical scavenging activity, measured by ORAC, was observed after 7 days of storage, in accordance with a shift of AC towards the reducing activity component. Overall, these findings indicate that sprouting approach using quinoa may provide highly antioxidant-enriched seedlings that may improve nutritional quality of diet or of functional foods. Interestingly, antioxidant properties of quinoa sprouts may be deeply influenced by storage, able to increase reducing activity by increasing phenols and vitamin C.

scholarly journals Re-evaluation of ABTS•+ Assay for Total Antioxidant Capacity of Natural Products

2015 ◽  
Vol 10 (12) ◽  
pp. 1934578X1501001 ◽  
Author(s):  
Jian-Wei Dong ◽  
Le Cai ◽  
Yun Xing ◽  
Jing Yu ◽  
Zhong-Tao Ding
Keyword(s):  
Natural Products ◽  
Antioxidant Capacity ◽  
Total Antioxidant Capacity ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Reaction Times ◽  
Universal Method ◽  
Stable Free Radical ◽  
Abts Assay ◽  
Total Antioxidant

2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation (ABTS•+) is a stable free radical frequently used for estimating the total antioxidant capacity (TAC) of natural products. The existing methods for ABTS•+ radical-scavenging activity assays are diverse in pre-diluting solvents and reaction time, which lead to errors in the TAC estimations. To develop an effective and universal method for estimating the ABTS•+ capacity accurately and reasonably, five pre-dilution solvents [methanol, ethanol, phosphate buffer (Na2HPO4-NaH2PO4, 200 mM, pH = 7.4), PBS buffer (Na2HPO4-NaH2PO4-NaCl, 200 mM, pH = 7.4), and distilled water] and different reaction times were investigated in ABTS•+ assays of five typical antioxidants. The results showed that the solvent effects were very significant. When using different pre-diluting solvents, different detection wavelengths should be selected. ABTS-+ assay could be measured within 2–10 min to obtain a rough result, which was mostly 6 min in the literature. However, full and accurate evaluation of antioxidant reactivity rather than capacity requires recording ABTS•+ loss continuously during the whole reaction period. The present study makes a recommendation for estimating the ABTS•+ capacity accurately and reasonably.

scholarly journals Polyphenol Composition and Antioxidant Capacity of Three Lysimachia Species

2014 ◽  
Vol 9 (10) ◽  
pp. 1934578X1400901 ◽  
Author(s):  
Anita Toth ◽  
Gergo Toth ◽  
Agnes Kery
Keyword(s):  
Radical Scavenging Activity ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Flavonoid Glycosides ◽  
Radical Scavenger ◽  
Polyphenol Content ◽  
Radical Scavenger Activity ◽  
External Standard Method ◽  
Scavenger Activity ◽  
Column Chromatographic

The polyphenol composition and antioxidant properties of three Lysimachia species ( L. nummularia L., L. vulgaris L. and L. punctata L.) and their column chromatographic fractions were investigated. The antioxidant activity of herb extracts and 54 different column chromatographic fractions was evaluated using in vitro DPPH• and ABTS•+ decolorization tests. The total polyphenol content was determined by spectrophotometric methods. The phenolic compounds of extracts of different Lysimachia species and their bioactive fractions were characterized by online chromatographic methods. For identification of the compounds, UV spectral data, accurate molecular mass and formula, as well as MS and fragmentation patterns given by LC-DAD-ESI/MS/MS and LC-ESI-TOF analyses were used. Quantification of the compounds was performed by LC-DAD using an external standard method. In the extracts, caffeic acid derivatives, chlorogenic acid, free flavonoid aglycones, and 11 various flavonoid glycosides were identified. Flavonoid composition of Lysimachia extracts showed significant differences. L. punctata extracts had the strongest DPPH• and ABTS•+ radical scavenger activity (IC50=43.3 μg/mL and 21.3 μg/mL), due to their high myricitrin and quercetin-hexoside content. Correlation between polyphenol content and radical scavenging activity of each column chromatographic fractions is also included.

scholarly journals Antioxidant Capacities of Jujube Fruit Seeds and Peel Pulp

2020 ◽  
Vol 10 (17) ◽  
pp. 6007 ◽  
Author(s):  
Yung-Sheng Lin ◽  
Wen-Shin Lin ◽  
Jing-Wen Tung ◽  
Ya-Chih Cheng ◽  
Min-Yun Chang ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Radical Scavenging Activity ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Reducing Power ◽  
Dry Weight ◽  
Total Phenolic ◽  
Scavenging Activity ◽  
Jujube Fruit

In this study, the effects of different fruit parts and extraction conditions on the antioxidant properties of jujube (Ziziphus jujuba Mill.) fruit were investigated. Five in vitro antioxidant models and statistical analyses were performed. The results revealed that jujube peel with pulp (peel pulp) exhibited better antioxidant capacity than did seeds. Overall, jujube peel pulp extracted using 50% ethanol at 60 °C exhibited the best antioxidant capacity in terms of 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (0.3 ± 0 mg/mL), 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity (0.5 ± 0 mg/mL), total phenolic content (38.3 ± 0.4 mg gallic acid equivalent per gram dry weight), total flavonoid content (43.8 ± 0.2 mg quercetin equivalent per gram dry weight), and reducing power (41.9 ± 2.2 mg ascorbic acid equivalent per gram dry weight). The results indicated that jujube peel pulp is a more potential natural antioxidant than seeds.

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