The Antioxidant and Antiproliferative Activities of 1,2,3-Triazolyl-L-Ascorbic Acid Derivatives

The novel 4-substituted 1,2,3-triazole L-ascorbic acid (L-ASA) conjugates with hydroxyethylene spacer as well as their conformationally restricted 4,5-unsaturated analogues were synthesized as potential antioxidant and antiproliferative agents. An evaluation of the antioxidant activity of novel compounds showed that the majority of the 4,5-unsaturated L-ASA derivatives showed a better antioxidant activity compared to their saturated counterparts. m-Hydroxyphenyl (7j), p-pentylphenyl (7k) and 2-hydroxyethyl (7q) substituted 4,5-unsaturated 1,2,3-triazole L-ASA derivatives exhibited very efficient and rapid (within 5 min) 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging activity (7j, 7k: IC50 = 0.06 mM; 7q: IC50 = 0.07 mM). In vitro scavenging activity data were supported by in silico quantum-chemical modelling. Thermodynamic parameters for hydrogen-atom transfer and electron-transfer radical scavenging pathways of anions deprotonated at C2-OH or C3-OH groups of L-ASA fragments were calculated. The structure activity analysis (SAR) through principal component analysis indicated radical scavenging activity by the participation of OH group with favorable reaction parameters: the C3-OH group of saturated C4-C5(OH) derivatives and the C2-OH group of their unsaturated C4=C5 analogues. The antiproliferative evaluation showed that p-bromophenyl (4e: IC50 = 6.72 μM) and p-pentylphenyl-substituted 1,2,3-triazole L-ASA conjugate (4k: IC50 = 26.91 μM) had a selective cytotoxic effect on breast adenocarcinoma MCF-7 cells. Moreover, compound 4e did not inhibit the growth of foreskin fibroblasts (IC50 > 100 μM). In MCF-7 cells treated with 4e, a significant increase of hydroxylated hypoxia-inducible transcription factor 1 alpha (HIF-1α) expression and decreased expression of nitric oxide synthase 2 (NOS2) were observed, suggesting the involvement of 4e in the HIF-1α signaling pathway for its strong growth-inhibition effect on MCF-7 cells.

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Inhibition of LDL oxidation by melatonin requires supraphysiologic concentrations

Clinical Chemistry ◽

10.1093/clinchem/44.9.1931 ◽

1998 ◽

Vol 44 (9) ◽

pp. 1931-1936 ◽

Cited By ~ 32

Author(s):

P Barton Duell ◽

David L Wheaton ◽

Amy Shultz ◽

Hien Nguyen

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Metal Ion ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Ldl Oxidation ◽

Human Macrophage ◽

Published Data ◽

Scavenging Activity ◽

Mediated Oxidation

Abstract Melatonin has been suggested as a potent antioxidant that may protect against development of atherosclerosis and cancer; however, these effects are unproven and controversial. The antioxidant capacity of melatonin was tested in comparison with α-tocopherol, ascorbic acid, and the melatonin precursors tryptophan and serotonin, by measuring inhibition of metal ion-mediated and human macrophage-mediated oxidation of LDL. Melatonin had weak antioxidant activity that was detectable only at concentrations 10 000- to 100 000-fold higher than physiologic concentrations. These results were comparable with published data showing that the radical scavenging activity of melatonin requires markedly supraphysiologic concentrations. In contrast, α-tocopherol was 50- to 100-fold more potent and was efficacious at physiologic concentrations. Ascorbic acid and tryptophan also were active at physiologic concentrations and were significantly more potent than melatonin. In summary, extremely supraphysiologic concentrations of melatonin had only weak antioxidant activity, which was surpassed by α-tocopherol, ascorbic acid, and tryptophan.

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Effect of Metal Ions (Cu2+/Fe2+) on the Antioxidant Activity of L-Ascorbic Acid-Glycine Model System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.28 ◽

2011 ◽

Vol 396-398 ◽

pp. 28-31

Author(s):

Cheng Yi Lei ◽

Da Zhai Zhou ◽

Rong Zhao ◽

Qi Hui Deng ◽

Ai Nong Yu ◽

...

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Maillard Reaction ◽

Antioxidative Activity ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Model System ◽

Model Systems ◽

Scavenging Activity ◽

Metal Concentrations

The influence of Cu2+, Fe2+ on the Maillard reaction were studied by heating L-ascorbic(ASA) and glycine (Gly) solutions adjusted to pH 5 at 120±2°C for 140 min in an oil bath. The presence of metals affected the intensity of browning and intermediate products, as monitored by absorbance at 420 nm and absorbance at 294 nm, sharply increased with the increase of metal concentrations applied (0.000M, 0.005M, 0.010M, 0.015M, 0.020M). Thereafter, slight increases were observed up to 0.020M. Antioxidative activity of all MRPs derived from ASA-Gly model systems sharply increased at 0.015M (P < 0.05) and slightly changes in activity were found with increasing metal concentrations up to 0.020M. Moreover, radical-scavenging activity correlated well with browning intensity and absorbance at 294 nm.

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Antioxidant Properties of Cashew Apple Wine (CAW)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.1645 ◽

2011 ◽

Vol 396-398 ◽

pp. 1645-1651 ◽

Cited By ~ 1

Author(s):

Qiu Ping Zhong ◽

Yong Cheng Li

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Free Radical ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Free Radical Scavenging ◽

Scavenging Activity ◽

Total Antioxidant Activity ◽

Total Antioxidant ◽

Reducing Capacity

In this study, total polyphenols content (TPC) and ascorbic acid content (AAC) in CAW were quantified. Total antioxidant activity, reducing capacity, and free radical scavenging activity of CAW were assayed. The TPC and AAC were 160 mg GAE /100ml and 132 mg/100 ml，respectivity. CAW exhibited effective antioxidant activities in the employed in vitro experiments, including total antioxidant activity, reducing capacity, and free radical scavenging activity, which indicates that phenolic compounds and ascorbic acid may play a key role in the antioxidant function of CAW.

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Phenolics and Carotenoids Contribute to Antioxidant Activity in Navel Orange

HortScience ◽

10.21273/hortsci.41.4.1000a ◽

2006 ◽

Vol 41 (4) ◽

pp. 1000A-1000

Author(s):

G.K. Jayaprakasha ◽

Clark Wilson ◽

Bhimanagouda S. Patil

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Ethyl Acetate ◽

Antioxidant Capacity ◽

Fruits And Vegetables ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Navel Orange ◽

Scavenging Activity ◽

Freeze Dried

Consumption of fruits and vegetables has been associated with reduced risk of disease, such as neurodegenerative disorders and certain forms of cancer, and aging. Antioxidants prevent the damage to macromolecules and cells by interfering with the free radicals. Several natural compounds that posses antioxidant activity have been reported from plant sources and are commercially promoted as nutraceuticals. Citrus fruits contain certain bioactive compounds such as phenolics, flavonoids, limonoids, carotenoids, and ascorbic acid. In this context, navel oranges were freeze-dried and extracted with five different solvents, such as hexane, ethyl acetate, acetone, methanol, and 8 methanol: 2 water. The extracts were dried under vacuum and screened for their radical scavenging activity using the 1,1-diphenyl-2-picrylhydrazyl method at 250, 500, and 1000 ppm. The methanol: water and methanol extracts of navel orange were found to be maximum (92.9%) and minimum (63.89%) radical scavenging activity at 1000 ppm. Furthermore, the antioxidant capacity of all extracts was assayed through the phosphomolybdenum method and expressed as equivalent to ascorbic acid (μmol/g of the extract). The order of antioxidant capacity for navel orange extracts was found to be ethyl acetate > acetone > methanol: water > methanol > hexane. It seems that the antioxidant capacity of the extracts is in accordance with the amount of phenolics/lycopene present in each fraction and may provide a good source of antioxidants. This project is based upon work supported by the USDA–CSREES under Agreement USDA IFAFS #2001-52102-02294 and USDA #2005-34402-14401 “Designing Foods for Health” through the Vegetable and Fruit Improvement Center.

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In vitro Assessment the Potential Antioxidant and Antitumor Activities of Bifidobacterium Derived Bacteriocins

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.9.2.15 ◽

2019 ◽

Vol 9 (02) ◽

Author(s):

Shadan A Alwendawi

Keyword(s):

Antioxidant Activity ◽

Human Cancer ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Cancer Drug ◽

Scavenging Activity ◽

Antitumor Activities ◽

Human Cancer Cell Lines ◽

Mcf 7

Nowadays there are increasing interest in using microbial bioactive peptides as therapeutic agents or as adjuvant to increase the effectiveness of available therapies, a promising approach in this line is using of probiotics secreted peptides. Bifidobacterium is one of the favorite patented probiotics genera and most of human enteric Bifidobacterium secretes bacteriocins peptides to the surroundings. Bifidobacterial – associated bacteriocins are classified as GRAS peptides, and recently were attracted attention that become a widespread research topic in various fields including cancer drug discovery development. This study was conducted to seek for antioxidant and antitumor activities of bifidobacterial – derived bacteriocins. Two bacteriocins, Bifidin B1 and Bifidin B2, were partially purified from enteric Bifidibacterium longum Bl and Bifidobacterium bifidum B2, respectively. Bifidins were physiochemically characterized in respective of thermal, pH, and storage stability. Their proteinaceous nature was confirmed. Potential antioxidant activity in terms of free radical scavenging activity was evaluated, both Bifidins exhibited antioxidant activity, the highest percentage scavenging activity against DPPH was 70.55±0.2673 %, recorded for Bifidin B1, and was followed by 68.1 ±1.753% scavenging capacity for Bifidin B2, while both of Bifidins B1 and B2 had almost close values for scavenging of superoxide anion radicals, 66 ± 1.970 % and 65.64 ± 1.343%, respectively. Bifidins demonstrated potential antitumor activity on two human cancer cell lines, MCF-7 and Skov-3, however, the antiproliferative activities does not exceed 60.8%. Bifidins B1 and B2 showed highest cytotoxicity against Skov-3 cells rather than MCF-7 cells, with IC50 values of 28.9± 8.76 µg/ml, and 29.87± 9.13 µg/ml, respectively.

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In vitro antioxidant activity of essential oil of aerial parts of Mentha pulegium L

Acta agriculturae Serbica ◽

10.5937/aaser2050193h ◽

2020 ◽

Vol 25 (50) ◽

pp. 193-197

Author(s):

Ahmed Hariri ◽

Naouel Ouis ◽

Djilali Bouhadi ◽

Zouaoui Benatouche

Keyword(s):

Lipid Peroxidation ◽

Antioxidant Activity ◽

Ascorbic Acid ◽

Essential Oil ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Dependent Manner ◽

Scavenging Activity ◽

Mentha Pulegium ◽

Pharmaceutical Industries

This work was conducted to evaluate the antioxidant activity of the essential oil obtained from the aerial part of Mentha pulegium. The antioxidant power of the essential oil obtained by hydrodistillation using a Clevenger-type apparatus was evaluated by using three methods: free radical-scavenging activity, reducing power and liver lipid peroxidation assay. Results showed that Mentha pulegium oil displayed good quality according to its physicochemical characteristics, and a higher yield 5.1 ± 0.2%. The essential oil of Mentha pulegium showed a higher DPPH radical scavenging activity 90.54 ± 1.5 % at a concentration of 1000 µg/mL. This value was close to the results obtained with ascorbic acid 96.23 ± 1.2%, and catechin 94.50 ± 1.4%. This oil exhibited significant potential for reducing iron (the value observed by optical density was 1.8 ± 0.3), while ascorbic acid and catechin provided an OD of 2.069 ± 0.03 and 2.66 ± 0.016 at the same concentration of 1000 µg/mL. The tested oil protected against lipid peroxidation induced by Fe+2, and considerably increased the percentage of anti lipid peroxidation in a dose-dependent manner. The studied oil displayed a good degree of antioxidant activity and can be exploited in food and pharmaceutical industries.

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Radical-Scavenging Compounds in Olive Fruits and their Changes during Table Olive Preparation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.295-298.118 ◽

2013 ◽

Vol 295-298 ◽

pp. 118-122 ◽

Cited By ~ 2

Author(s):

Li Qin Jiang ◽

Hitoshi Takamura

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Antioxidant Compounds ◽

Scavenging Activity ◽

Active Compounds ◽

Table Olive ◽

Radical Scavenging Compounds

The aim of this study was to determine the changes of antioxidant activity and antioxidative compounds during table olive preparing by different procedures. The extraction of antioxidants from table olive is studied considering different debittering procedure (alkali treated or brine treated) to investigate the selectivity of the process. The radical-scavenging activity (RSA) of 1,1-diphenyl-2-picrylhydrazyl (DPPH•) and determination of the antioxidant compounds (total phenol, ascorbic acid and tocopherol) are applied to evaluate the antioxidant activity and antioxidative compounds of table olive. The active compounds and DPPH-RSA decreased during table olive preparation. A large amount of the active compounds lost during “alkali treated” except tocopherol. Little amount of the active compounds remained in “brine treated” table olive.

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The Nutritional Composition, Antioxidant Activity and Common Phytochemicals of Selected BARI Mango Varieties and Commercial Cultivar Langra

European Journal of Agriculture and Food Sciences ◽

10.24018/ejfood.2020.2.6.151 ◽

2020 ◽

Vol 2 (6) ◽

Author(s):

Mohammad Mainuddin Molla ◽

Ashfak Ahmed Sabuz ◽

Md. Golam Ferdous Chowdhury ◽

Md. Hafizul Haque Khan ◽

Mahfujul Alam ◽

...

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Free Radical ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Reducing Power ◽

Nutritional Composition ◽

Free Radical Scavenging ◽

Anthocyanin Content ◽

Scavenging Activity

The present study sought to explore the nutritional composition, bioactive phytochemicals and antioxidant activity of BARI mango-4, BARI mango-6 and Langra cultivar. The total phenolic (TPH), vitamin C, total carotene, ß-carotene content and antioxidant activity of the mangos were determined by 1,1- diphenyl-2picryl hydrazyl (DPPH) scavenging and reducing power assays (RPA). Phenolic compounds were assessed using high-performance liquid chromatography coupled with a photodiode array detector and auto sampler. Results revealed that moisture, TSS, pH, total acidity, reducing, total sugar and energy of the BARI mango-4 and BARI mango-6 were 76.54 and 75.24 %, 17.10°B and 21.20°B, 4.90 and 5.01, 0.49 and 0.50 %, 3.90 and 4.54 %, 11.20 and 13.46 % and 4028.06 and 3950.27 cal/g respectively whereas the Langra cultivar remained 76.33 %, 17.63°B, 4.25, 0.63 %, 2.79 %, 9.79 % % and 3871.28 cal/g respectively. Phytochemicals especially TPH, ascorbic acid, total flavonoid (TF), total carotenoid (TC), ß-carotene and total anthocyanin content (TAC) of the BARI mango-4 and BARI mango-6 were 20.53 and 20.67 mg GAE/g, 39.98 and 26.26 mg/100 g, 3.14 mg and 2.87 QE/g, 76.38 and 81.33 mg/100 g, 28.17 and 65.84 µg/100 g and 1.67 and 11.69 mg/100 respectively whereas the Langra contained 19.90 mg GAE/g, 25.53 mg/100g, 1.38 mg QE/g, 4.21 mg/100 g, 31.00 µg/100 g and18.22 mg/100 g respectively. In case of antioxidant activities total antioxidant capacity, DPPH radical scavenging activity, reducing power capacity (RPC), metal chelating capacity (MCC), Nitric oxide (NO) free radical scavenging activity and IC50 of the BARI mango-4 and BARI mango-6 were 229.00 and 309.00 µg of ascorbic acid/mg of extract, 96.84 and 94.73 %, 12.20 and 9.71 µg/mL, 157.36 and 132.89 %, 61.74 and 72.65 µg/mL and 0.59 and 0.71 µg/mL respectively whereas the Langra cultivar contained 194.25 µg of ascorbic acid/mg of extract, 87.94 %, 2.54 µg/mL, 177.80 %, 53.74 µg/mL and 25.11 µg/mL respectively. The results indicate that BARI mango-4 and BARI mango-6 exhibited rich source of TPH, TC, ß-carotene, ascorbic acid, TA, TAC and NO free radical scavenging activity whereas the Langra is the rich source of MCC and anthocyanin content. Phenolic acids were leading agent in BARI mango-4 and BARI mango-6. Moreover, BARI mango-4 and BARI mango-6 extract had a great potential to fight free radical chain reactions and for usage in therapeutic applications.

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Antioxidant Activity of `Rio Red', `Marsh White', and Commercial Juice In Vitro Model Systems

HortScience ◽

10.21273/hortsci.40.4.1135b ◽

2005 ◽

Vol 40 (4) ◽

pp. 1135B-1135

Author(s):

Basavaraj Girennavar ◽

Bhimanagouda Patil ◽

Guddadarangavvanahally Jayaprakasha

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Ethyl Acetate ◽

Antioxidant Capacity ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Model Systems ◽

Scavenging Activity ◽

Plant Materials ◽

Dpph Method

Antioxidant activity is widely used as a parameter to characterize different plant materials for potential health benefits. This activity is related with compounds capable of protecting a biological system against the harmful effect of reactions that can cause excessive oxidation, involving reactive oxygen and nitrogen species (RONS). There has been growing interest in the beneficial health effects of consuming fruits and vegetables. Mainly, the presence of lycopene, ascorbic acid, and phenolic antioxidants is believed to have the protective mechanism. The free radical-scavenging activities of grapefruit extract of `Rio Red', `Marsh White', and commercial juice were extracted with different solvents, such as hexane, ethyl acetate, and chloroform. The dried extracts were screened for their radical scavenging activity using the α,α -diphenyl-β-picrylhydrazyl (DPPH) method. The ethyl acetate extracts of commercial juice and `Marsh White' were found to possess more radical scavenging activity compared with the other two extracts. However, chloroform extracts of `Rio Red' grapefruit were the most active, which may be ascribed to the presence of more lycopene. Furthermore, the antioxidant capacity of `Rio Red' and `Marsh White' extracts was assayed through the phosphomolybdenum method and expressed as equivalent to ascorbic acid (μmol·g-1 of the extract). The order of antioxidant capacity for `Rio Red' extracts was found to be hexane > chloroform > ethyl acetate, while the order for `Marsh White' was chloroform > hexane > ethyl acetate. The results indicate that the extent of antioxidant activity of the extract is in accordance with the amount of lycopene/phenolics present in that extract; commercial juice and `Rio Red' may provide a good source of antioxidants.

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