scholarly journals Effect of Physiological Concentrations of Vitamin C on the Inhibitation of Hydroxyl Radical Induced Light Emission from Fe2+-EGTA-H2O2 and Fe3+-EGTA-H2O2 Systems In Vitro

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1993
Author(s):  
Michal Nowak ◽  
Wieslaw Tryniszewski ◽  
Agata Sarniak ◽  
Anna Wlodarczyk ◽  
Piotr J. Nowak ◽  
...  

Ascorbic acid (AA) has antioxidant properties. However, in the presence of Fe2+/Fe3+ ions and H2O2, it may behave as a pro-oxidant by accelerating and enhancing the formation of hydroxyl radicals (•OH). Therefore, in this study we evaluated the effect of AA at concentrations of 1 to 200 µmol/L on •OH-induced light emission (at a pH of 7.4 and temperature of 37 °C) from 92.6 µmol/L Fe2+—185.2 µmol/L EGTA (ethylene glycol-bis (β-aminoethyl ether)-N,N,N′,N′-tetraacetic acid)—2.6 mmol/L H2O2, and 92.6 µmol/L Fe3+—185.2 µmol/L EGTA—2.6 mmol/L H2O2 systems. Dehydroascorbic acid (DHAA) at the same range of concentrations served as the reference compound. Light emission was measured with multitube luminometer (AutoLumat Plus LB 953) for 120 s after automatic injection of H2O2. AA at concentrations of 1 to 50 µmol/L and of 1 to 75 µmol/L completely inhibited light emission from Fe2+-EGTA-H2O2 and Fe3+-EGTA-H2O2, respectively. Concentrations of 100 and 200 µmol/L did not affect chemiluminescence of Fe3+-EGTA-H2O2 but tended to increase light emission from Fe2+-EGTA-H2O2. DHAA at concentrations of 1 to 100 µmol/L had no effect on chemiluminescence of both systems. These results indicate that AA at physiological concentrations exhibits strong antioxidant activity in the presence of chelated iron and H2O2.

2021 ◽  
Vol 913 (1) ◽  
pp. 012093
Author(s):  
U Fitrotin ◽  
N Hilmiati ◽  
Mardiana ◽  
Y Triguna ◽  
A Surahman ◽  
...  

Abstract Preparation process for meniran (Phillantus urinaria) functional drink (MFD) influences its antioxidant activity. This research aims to understand the phenolic content, DPPH Radical Scavenging Activity (RSA), and LDL oxidation of MFD through various preparation processes. Those preparation processes included soaking fresh meniran (SFM), boiling fresh meniran for 5 minutes (BFM5’), boiling fresh meniran for 10 minutes (BFM10’), and soaking dried meniran (DM). The phenolic content was determined with Folin–Ciocalteu, antioxidant activity was assessed using DPPH and TBARS assay with LDL as the oxidation substrate. An antioxidant references in this research used ascorbic acid. The phenolic content in methods of SFM, BFM5’, BFM10’ and DM were 122±0.022, 182±0.043, 192 ±0.03, and 117 ±0.019 mg GAE/g of meniran respectively. Meanwhile, the DPPH RSA of SFM, BFM5’, BFM10’ and DM accounted for 82.18±0.35, 86.19±0.53, 86.75±0.64 and 69.96% respectively. As comparison, the DPPH RSA of ascorbic acid 50 ppm is 75.65±0.82%. At the same time the optimum inhibition of TBARS formation from BFM5’ and BFM10’ methods were 45.83 % and 48.66%, with MDA concentration in human LDL accounted for 38.30±2.39 and 36.30±1.82 nmol MDA/mg protein, respectively. As comparison, MDA concentration in human LDL added with ascorbic acid 25 ppm accounted for 41.35±2.41 nmol MDA/mg protein. In contrast, the control human LDL was 70.70±2.35 nmol MDA/mg protein. This study concludes that the BFM5’ and BFM10’ methods showed the highest antioxidant properties compared to other methods. All methods showed that MFD extract in concentration more than 25 ppm increased the concentration of MDA in human LDL. Therefore, to produce meniran functional drink in optimum antioxidant properties is best by using BFM5’ and BFM10’ preparation methods in meniran concentration of not more than 25 ppm.


Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5829
Author(s):  
Alejandra Bermúdez-Oria ◽  
Yougourthane Bouchal ◽  
África Fernández-Prior ◽  
Blanca Vioque ◽  
Juan Fernández-Bolaños

The natural antioxidant hydroxytyrosol (HT) was used to functionalize a strawberry puree. The effect of the antioxidant on the stability of the two bioactive forms of vitamin C (ascorbic acid-AA and dehydroascorbic acid-DHAA) in strawberry puree stored at 4 °C, compared with the effect on a model system of AA in water, was investigated. In the absence of HT, the concentration of vitamin C in strawberry puree decreased but not in the model system. Low concentrations of HT in strawberry puree (0.05 and 0.1 mg HT/g puree) stabilized vitamin C and improved its antioxidant activity. However, at high concentrations of HT (from 0.5 mg HT/g puree), although the antioxidant activity improved, degradation of vitamin C occurred. Therefore, the concentration of HT used to obtain a functionalized strawberry puree it is very important. An adequate concentration increases the antioxidant activity and protects vitamin C from degradation, developing a functional food. However, an inadequate concentration of HT affects the vitamin C content, which is essential for the human diet because it cannot be biosynthetized by the organism.


2019 ◽  
Vol 15 ◽  
Author(s):  
Aleksandra Kładna ◽  
Paweł Berczyński ◽  
Oya Bozdağ Dündar ◽  
Irena Kruk ◽  
Beyza Torun ◽  
...  

Background: Stilbene phytalexis (1,2-diphenyloethylen) and benzamide are beneficial for human health. To increase the stilbene ring activity, a new series of its derivatives containing benzamide structure was synthesized and evaluated for their in vitro antioxidant power. Methods: 1H nuclear magnetic resonance, mass spectroscopy, and chromatographic analyses were used to confirm the successful synthesis. The antioxidant properties were determined by the elimination of , HO , DPPH , ABTS+ radicals, total antioxidant status (TAS) and the ferric reducing antioxidant activities (TAC) measurements. Results: Stilbenebenzamide compounds showed a wide spectrum of antioxidant ability, however their total antioxidant power was weaker than those of butylated hydroxytoluene (BHT), ascorbic acid, and resveratrol. The highest antiradical activity towards and HO was shown by the compounds with structures containing amine group (SBEBA, SBA) ( : 37.7 – 38.0% and 40.8 – 43.5%, HO : 29.8%, 28.7% inhibition, respectively) at1.25 mM concentration. The antiradical power of SBEBA (0.29) in DPPH assay was lower than those of resveratrol (1.83), ascorbic acid (3.63) and BHT (4.09). The TAS values of the synthesized compounds ranged from 152.9±5.3 to 240.2±6.7µM trolox equivalent/gram (TE/g) and were much lower than those of BHT (1304±43.0), reservatrol (1360±29.0) and ascorbic acid (2782±39.7) µM TE/g. Similarly, the TAC values ranging from 29.7±0.9 to 41.5±1.6 µM TE were weaker than that of resveratrol (239.2 ±6.7 µM TE/g). Conclusion: The results suggest that the presence of hydroxyl group in stilbene ring should be considered in further design of stilbenebenzamide compounds to enhance their antioxidant activity.


Author(s):  
Dipti Acharya ◽  
Umesh Kumar Gilhotra ◽  
Ranjan Singh ◽  
Himanshu Rajpurohit ◽  
Ajay Gar

Antioxidant play an important role to protect damage caused oxidative stress (OS).Chlorophyll having phenolic contents are reported to possess antioxidant properties. The present study was designed to investigate the antioxidant properties of methanolic solution from Super Chlorophyll. Objective: The main objective of the study was to evaluate the antioxidant activity of the chlorophyll in different validated in vitro models. Methods: The antioxidant activities of methanolic solution were evaluated by in vitro standard method using UV-Spectrophotometer. The antioxidant activity were determined bt total antioxidant capacity, DPPH (1-1-diphennyl-2-picrylhydrzine) radical scavenging assay, Nitric Oxide scavenging assay and Hydrogen Peroxide scavenging assay methods. Result: The solution of Chlorophyll was studied for antioxidant potential. Ascorbic acid was used as standard. This method is simple and activity of the solution is reported in term of IC50 value. Antioxidant properties depend on the IC50 value. Lesser the IC50 value, more is the antioxidant activity. Chlorophyll showed good antioxidant activity. Conclusion:  In case of in vitro antioxidant activity, Chlorophyll scavenged DPPH, hydrogen peroxide, nitric oxide radicals significantly, showed IC50 values near to standard ascorbic acid, thus proving to have good antioxidant potential. Keywords: Oxidative stress, DPPH, Antioxidant, Super chlorophyll.


2016 ◽  
Vol 7 (2) ◽  
pp. 67 ◽  
Author(s):  
Gustavo Araujo Pereira ◽  
Pedro Henrique Ferreira Tomé ◽  
Henrique Silvano Arruda ◽  
Edson José Fragiorge ◽  
Paulo Roberto Ribeiro

The objective of this work was to determine the physical and physicochemical characteristics, proximate composition, antioxidant activity, total phenolic compounds, vitamin C content and total anthocyanins of different fractions of the calabura fruits (peel, pulp and whole fruit). The fruits showed average diameter and weight of 14.50 mm and 1.57 g, respectively, and high yield in pulp (75.38%). The whole fruit showed: pH (5.64), titratable acidity (0.11 g citric acid 100 g-1), soluble solids (10.24 °Brix), ratio (93.76), moisture (77.36%), ash (5.65%), lipids (7.79%), proteins (8.29%), crude fiber (5.93%), carbohydrates (72.15%), vitamin C (3.30 mg 100 g-1), phenolic compounds (526.55 mg tannic acid equivalents (TAE) 100 g-1), anthocyanins (4.08 mg cyanidin-3-glucoside equivalents (CGE) 100 g-1) and DPPH IC50 (82.25 μg mL-1).The peel showed high antioxidant activity (82.00 μg mL-1) due to the highest contents of phenolic compounds (868.90 mg TAE 100 g-1), anthocyanins (3.87 mg CGE 100 g-1) and vitamin C (4.20 mg 100 g-1). In conclusion, the calabura fruit showed high content of bioactive compounds with antioxidant properties in vitro.


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Hashini I. Abeysuriya ◽  
Vajira P. Bulugahapitiya ◽  
Jayatissa Loku Pulukkuttige

Sri Lanka is rich in a wide diversity of fruits, but many are underutilized by the people in Sri Lanka despite their nutritional value. This is mainly due to little awareness of the palatability of many fruits and hence low popularity in the market. The present study aimed at providing comparative data on the main biochemical and nutritional parameters of thirty-seven (37) species of fruits grown in Sri Lanka, including 22 underutilized fruits and 15 commonly consumed fruits. The main parameters of the comparison were the contents of ascorbic acid (AA), total vitamin C (TVC), total phenolic content (TPC), total flavonoid content (TFC), total iron (Fe), and antioxidant capacities (ACs). The mean AA, TVC, TPC, TFC, and Fe contents in 100 g of fresh edible portions of fruits ranged from 2.0 to 185.0 mg, 8.1 to 529.6 mg, 12.9 to 2701.7 mg gallic acid equivalent, 0.2 to 117.5 mg quercetin equivalents, and 0.1 to 1.1 mg, respectively. The IC50 values in a DPPH assay varied between 0.8 to 1856.7 mg/mL and FRAP values in a FRAP assay ranged from 4.2 to 2070 μmol FeSO4/g in the studied fruits. Fruits were ranked based on the levels of the abovementioned biochemical properties. Using this ranking, 12 of the top 15 fruits were underutilized. Phyllanthus emblica (Indian gooseberry) is at the top of these underutilized fruits, and Psidium guajava (guava) is the best among commonly consumed fruits. These results indicate that underutilized fruits in Sri Lanka can be recommended as high quality and low-cost alternatives for securing nutritional requirements. Hence, underutilized fruits can be promoted as healthy additional fruits in Sri Lanka.


2020 ◽  
Vol 11 (2) ◽  
pp. 1571-1577
Author(s):  
Lakshminarayanan B ◽  
Kannappan N ◽  
Subburaju T ◽  
Kalaichelvan V K

Pyrazolines are the most useful heterocyclic moiety in Pharmaceutical and Chemical fields and as the most potential molecules for the design of new chemical entities. Nitrogen-containing heterocyclic compounds, pyrazolines and their derivatives showed a variety of pharmacological activities, including antioxidant properties. In the present study, eleven novel ethoxylated pyrazoline derivatives were synthesized by condensing chalcones with electron releasingethoxy group at one end and different electron-donating, electron-withdrawing groups in another end with hydrazine hydrate andalcohol. The compounds synthesized were structural elucidated by their spectroscopic studies. All the compounds synthesized were evaluated for their in vitro antioxidant potential by 2,2’-diphenyl-1-picrylhydrazyl (DPPH)and hydrogen peroxide free radical scavenging assay methods.Some of these molecules possess moderate to good antioxidant activitywhen compared to standard ascorbic acid. The compound with methoxy group (EH2) exhibits potent antioxidant activity with IC50 value of 9.02 and 9.44µg/ml in DPPH and hydrogen peroxide assay method respectively and the compound with hydroxy group (EH9) also showed potent antioxidant activity with IC50 value of 12.41 and 14.56µg/ml in DPPH and hydrogen peroxide free radical scavengingassay method respectively when compared to standard. The compounds containing electron-donating substituents were found to be good antioxidantswhen compared to standard ascorbic acid.


Antioxidants ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 197 ◽  
Author(s):  
Guadalupe Firpo ◽  
María L. Ramírez ◽  
Martín S. Faillace ◽  
Maria dos R. Mendes de Brito ◽  
Ana P. S. Correia Lima e Silva ◽  
...  

The growing interest in the chemistry of unsaturated ring-fused 1,3-heterocycles, in this particular case 1,3-oxazines, arise in part from their versatile pharmacological applications. In the present article, the evaluation of the in vitro and ex vivo antioxidant activity of two cyclohexene-fused oxazines is discussed. The in vitro antioxidant activity was evaluated by trapping the ABTS and hydroxyl radicals as well as the inhibition of the enzyme acetyl-cholinesterase and hemolysis of erythrocytes by 2,2’-Azobis(2-amidinopropane) dihydrochloride (AAPH). The results suggest that both unsaturated 1,3-oxazines are auspicious sources of biologically active compounds with good antioxidant properties. In addition, a comprehensive analysis of the interaction between these heterocycles with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals, as well as the measurements of redox potential, provided evidence for a mechanism of antioxidant activity that takes place through electron transfer (ET) processes.


2014 ◽  
Vol 3 (4) ◽  
pp. 41 ◽  
Author(s):  
Antonello Santini ◽  
Raffaele Romano ◽  
Giuseppe Meca ◽  
Assunta Raiola ◽  
Alberto Ritieni

<p>Dietary recommendations include the consumption of fresh apples and processed apple based products mainly for the antioxidant properties associated to the polyphenols, and vitamin C content. Thermal treatment, generally used to extend shelf life of fruit based foodstuff, can affect the quality. 5-hydroxymethylfurfural (5-HMF), reducing sugars, ascorbic acid, and the total antioxidant activity in bio available fraction after <em>in vitro</em> digestion, have been evaluated in 16 apple-based nectars (fruit content: 30-60%), 15 apple-based juices (fruit content 100%) and 5 apple-based puree. Observed data indicate a 5-HMF values ranging from 0.06 mg/L in juices to 28.61 mg/L in nectars. The reducing sugar amount did not vary significantly between the three analysed typology of apple derivatives, while the ascorbic acid content was quite high compared to reported literature data. The antioxidant activity after an <em>in vitro</em> digestion showed values ranging from 0.21 to 7.68 mmol of Trolox in juices, and puree, respectively.</p>


2021 ◽  
Vol 34 (1) ◽  
pp. 84-93
Author(s):  
Marwah T. G. Al-Ameri ◽  
Amera K. Nasser

The experiment was conducted in the laboratories of the College of Agriculture, University of Basra, for the period from 22/9/2019 to 25/ 11/2019. The current study aims to extract gum from the carob fruits, to determine the active substances and the possibility of using them as antioxidants. The results showed that the gum of the fruits of the carob plant contains all the active compounds under study, which included Alkaloids, Phenols, Flavonoids, Glycosides, Steroids, Tannins, Resins, Saponins and Coumarins. The results also showed that the gum of the fruits of the carob plant showed antioxidant activity of about 84.55 % when used at a concentration of 0.2 %, while the average antioxidant efficacy of the industrial compound Butylated Hydroxy Toluene (BHT) and Ascorbic acid was about 93.43 %, 91.12 % at the same concentration. The Reductive power were about 73.20 % and 83.30 % with a concentration of 0.1 % and 0.2 % respectively, which was comparable to the effect of industrial antioxidants (BHT) and ascorbic acid with a concentration of 0.2 %, which was 91.40 % and 90.70 %, respectively. In addition, the gum of the fruits of the carob plant has the potential to sweep hydrogen peroxide with a capacity similar to ascorbic acid and without significant difference (p≤0.05), reaching 41 % and 50 % for concentrations 0.1 % and 0.2 %, respectively, while ascorbic acid reached 45 % with the presence of moral differences with the industrial antioxidant (BHT) in its susceptibility to the sweep of hydrogen peroxide at 73 %. The results also showed that the gum of the fruits of the carob plant is able to bind to the Ferrous ion and this portability increased with the increased concentration of gum to reach its highest average of 43.19 % at the concentration of 0.2 % while the average Ferrous ion for antioxidant (EDTA 2Na) was 55.48 %.


Sign in / Sign up

Export Citation Format

Share Document