scholarly journals Systematic Evaluation and Mechanistic Investigation of Antioxidant Activity of Fullerenols Usingβ-Carotene Bleaching Assay

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Hiroshi Ueno ◽  
Shizuka Yamakura ◽  
Riya S. Arastoo ◽  
Takumi Oshima ◽  
Ken Kokubo
Keyword(s):  
Antioxidant Activity ◽  
Methyl Linoleate ◽  
Peroxyl Radical ◽  
Radical Scavenging ◽  
Model Reaction ◽  
Systematic Evaluation ◽  
Oh Groups ◽  
Mechanistic Investigation ◽  
High Antioxidant Activity ◽  
Tof Ms

Antioxidant activity of hydroxylated fullerenes, so-called fullerenols, against lipid peroxyl radical was evaluated byβ-carotene bleaching assay. All samples showed moderate to high antioxidant activity (%AOA), especially for C60(OH)12(70.1) and C60(OH)44(66.0) as compared with 8, 24, 26, and 36 hydroxylated ones (31.7–62.8). The detection of the possible products was conducted in the model reaction of both fullerenols and C60with methyl linoleate by MALDI-TOF-MS. These results suggested that the two possible mechanisms, such as C-addition to double bonds and H-abstraction from –OH groups, are involved in the present radical scavenging reaction.

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

2019 ◽  
Vol 20 (19) ◽  
pp. 4735 ◽  
Author(s):  
Anja Harej ◽  
Andrijana Meščić Macan ◽  
Višnja Stepanić ◽  
Marko Klobučar ◽  
Krešimir Pavelić ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Ascorbic Acid ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Hydrogen Atom Transfer ◽  
Breast Adenocarcinoma ◽  
Scavenging Activity ◽  
Activity Data ◽  
Oh Groups ◽  
Mcf 7

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.

scholarly journals Effect of Nanocrystallization of Anthocyanins Extracted from Two Types of Red-Fleshed Apple Varieties on Its Stability and Antioxidant Activity

Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3366 ◽  
Author(s):  
Jihua Xu ◽  
Xinxin Li ◽  
Shifeng Liu ◽  
Peilei Zhao ◽  
Heqiang Huo ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Corn Starch ◽  
Uv Light ◽  
Radical Scavenging ◽  
Malus Sieversii ◽  
Total Anthocyanins ◽  
High Antioxidant Activity ◽  
Starch Nanoparticles ◽  
The Stability

Red-fleshed apple (Malus sieversii f. neidzwetzkyana (Dieck) Langenf) has attracted more and more attention due to its enriched anthocyanins and high antioxidant activity. In this study we extracted total anthocyanins and phenols from two types of red-fleshed apples—Xinjing No.4 (XJ4) and Red Laiyang (RL)—to study the stability and antioxidant activity of anthocyanins after encapsulation onto Corn Starch Nanoparticles (CSNPs). The results indicated the anthocyanins and total phenol levels of XJ4 were 2.96 and 2.25 times higher than those of RL respectively. The anthocyanin concentration and loading time had a significant effect on CSNPs encapsulation, and XJ4 anthocyanins always showed significantly higher loading capacity than RL. After encapsulation, the morphology of RL-CSNPs and XJ4-CSNPs was still spherical with a smooth surface as CSNPs, but the particle size increased compared to CSNPs especially for RL-CSNPs. Different stress treatments including UV light, pH, temperature, and salinity suggested that XJ4-CSNPs exhibited consistently higher stability than RL-CSNPs. A significantly enhanced free radical scavenging rate under stress conditions was observed, and XJ4-CSNPs had stronger antioxidant activity than RL-CSNPs. Furthermore, XJ4-CSNPs exhibited a slower released rate than RL-CSNPs in simulated gastric (pH 2.0) and intestinal (pH 7.0) environments. Our research suggests that nanocrystallization of anthocyanins is an effective method to keep the anthocyanin ingredients intact and active while maintaining a slow release rate. Compared to RL, encapsulation of XJ4 anthocyanins has more advantages, which might be caused by the significant differences in the metabolites of XJ4. These findings give an insight into understanding the role of nanocrystallization using CSNPs in enhancing the antioxidant ability of anthocyanins from different types of red-fleshed apples, and provide theoretical foundations for red-fleshed apple anthocyanin application.

A DFT STUDY ON THE ROLE OF DIFFERENT OH GROUPS IN THE RADICAL SCAVENGING PROCESS

2012 ◽  
Vol 11 (04) ◽  
pp. 871-893 ◽  
Author(s):  
K. SADASIVAM ◽  
R. JAYAPRAKASAM ◽  
R. KUMARESAN
Keyword(s):  
Antioxidant Activity ◽  
Density Functional ◽  
Dominant Role ◽  
Food Additives ◽  
Radical Scavenging ◽  
Theory Approach ◽  
Oh Groups ◽  
Flavonoid Compounds ◽  
Dissociation Enthalpy

The molecular properties of robinetin and melanoxetin which are the two naturally occurring flavonoid compounds have been studied theoretically by means of density functional theory approach (DFT) at the level of B3LYP/6-311G(d,p). The analysis of computed bond dissociation enthalpy (BDE), proton dissociation enthalpy (PDE), proton affinity (PA), electron transfer enthalpy (ETE) values for both the flavonoid compounds indicate the role of B-ring for the significant antioxidant characteristics and the instability of the A-ring. It also concerns the dominant role of BDE mechanism for antioxidant activity than PDE, PA and ETE mechanisms. Ionization potential (IP) is also found to be trustworthy in the study of antioxidant activity and the computed IP magnitudes are in agreement with the values of synthetic food additives. Further, the various molecular descriptors along with the plot of frontier molecular orbitals and Mulliken spin population analysis have been obtained and the validity of Koopmans' theorem is also verified with reference to antioxidant behavior.

Synthesis of various β-D-glucopyranosyl and β-D-xylopyranosyl hydroxybenzoates and evaluation of their antioxidant activities

2017 ◽  
Vol 23 (3) ◽  
pp. 213-223 ◽  
Author(s):  
Yasutaka Shimotori ◽  
Masayuki Hoshi ◽  
Yosuke Osawa ◽  
Tetsuo Miyakoshi
Keyword(s):  
Methyl Linoleate ◽  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Inhibitory Effect ◽  
Novozym 435 ◽  
Regioselective Deacetylation ◽  
Hydroxybenzoic Acids ◽  
High Antioxidant Activity ◽  
Dpph Radical Scavenging

AbstractVarious β-D-glucopyranosyl and β-D-xylopyranosyl hydroxybenzoates were efficiently prepared from 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide (TAGB) or 2,3,4-tri-O-acetyl-α-D-xylopyranosyl bromide (TAXB), respectively, by amine-promoted glycosylation. Regioselective deacetylation of the resulting acetylated β-D-gluco- and β-D-xylopyranosyl hydroxybenzoates was investigated using Novozym 435 as a lipase catalyst. In the case of β-D-glucopyranosyl hydroxybenzoates, Novozym 435-catalyzed deacetylation is regioselective at C-4 and C-6 positions. On the other hand, β-D-xylopyranosyl hydroxybenzoates are deacetylated only at the C-4 position. Antioxidant activities of free hydroxybenzoic acids and the respective β-D-gluco- and β-D-xylopyranosyl hydroxybenzoates were evaluated by DPPH˙ radical scavenging as well as their inhibitory effect on autoxidation of bulk methyl linoleate. The β-D-xylopyranosyl protocatechoate, as well as quercetin and α-tochopherol, show high antioxidant activity for the radical scavenging activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH˙). In bulk methyl linoleate, the antioxidant activities of β-D-gluco- and β-D-xylopyranosyl protocatechoates are higher than that of α-tocopherol.

scholarly journals Mongolian crude propolis content analysis and antioxidant activity

2019 ◽  
Vol 27 (02) ◽  
pp. 34-39
Author(s):  
Ichinkhorloo P ◽  
Gantsetseg G ◽  
Selenge Kh ◽  
Undrakhbayar Ts ◽  
Otgonsugar P ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Amino Acid ◽  
Radical Scavenging ◽  
Antioxidant Effect ◽  
Chemical Components ◽  
Total Amino Acid ◽  
Geographic Origins ◽  
Chemical Content ◽  
High Antioxidant Activity ◽  
Dpph Radical Scavenging

Propolis, a precious bee product has been widely used for pharmaceutical purposes for centuries. Chemical components, properties, and activities are differed based on geographic origins, respective plant sources, and bee species. In our research, Mongolian propolis from 2 different places was examined for chemical content and antioxidant effect. The samples were collected from Northern and Central parts of Mongolia and were examined for a total of 8 contents. Crude Mongolian propolis sample from central part of Mongolia displayed higher results in every aspect with total moisture of 2.1%; ash 1.7%; fat 67.8, 69.3%; and 1.05% of protein. The free amino acid in 70% EtOH was higher in sample from northern part with 1.21µg/mg and the total amino acid was quantified by HPLC and highest concentration detected in methionine 1.90mg/g, and 2.62 mg/g. Totally 3 alkaloids and 2 phenolic were detected by TLC and high antioxidant activity was presented in DPPH radical scavenging test. The results suggest that the best solvent for propolis samples is EtOH 70% solution. The test propolis samples contain different types of alkaloids and phenolic, have high amount of methionine and has high antioxidant effect. 

scholarly journals Characterization of The Physicochemical Properties, Antioxidant Activity, And Antiproliferative Activity of Natural Melanin From S. Reiliana

2021 ◽  
Author(s):  
Ming Lu ◽  
Mengxi Xie ◽  
Xin Fu ◽  
Miao Yu ◽  
Taiyuan Shi
Keyword(s):  
Antioxidant Activity ◽  
Physicochemical Properties ◽  
Food Additives ◽  
Radical Scavenging ◽  
Hydroxyl Groups ◽  
Health Food ◽  
Sporisorium Reilianum ◽  
High Antioxidant Activity ◽  
Radical Scavenging Ability ◽  
Dopa Melanin

Abstract This study aimed to characterize the physicochemical properties and stability of L-25 melanin extracted from Sporisorium reilianum (S. reiliana). The results showed that the maximum absorption wavelength of melanin was 215 nm. Reducing agents, heat, light, microwaving, oxidants, and common food additives did not affect the melanin. Additionally, it has a good metal stability except Mn2+. The IR spectra revealed the presence of O-H, N-H, C=O, and C=C bonds as well as carboxyl, alcohol hydroxyl, and phenolic hydroxyl groups and a pyran ring. L-25 melanin could be defined as DL-hydroxy phenylalanine (DOPA)-melanin. The antioxidant and antiproliferative were also measured. The melanin has a specific stability and high antioxidant activity, including a strong DPPH free radical scavenging ability, and protected damaged HepG2 cells by reducing reactive oxygen species, malondialdehyde, and lactate dehydrogenase content. In conclusion, S. reilianum represents a novel source of melanin, that could be applied to health food or food additives. Our results show that melanin from S. reilianum is a natural pigment with good stability that has a great prospect of development and application, providing a theoretical basis and methods for its further processing and development as a functional food.

scholarly journals In- vitro antioxidant and In vivo Anti-inflammatory Potentials of Marantochloa Leucantha (Marantaceae) Extracts and Fractions

2019 ◽  
Vol 18 (2) ◽  
pp. 233-240
Author(s):  
Wilfred O Obonga ◽  
Charles O Nnadi ◽  
Chinonye C Chima ◽  
Sunday N Okafor ◽  
Edwin O Omeje
Keyword(s):  
Antioxidant Activity ◽  
Radical Scavenging ◽  
Paw Edema ◽  
Frap Assay ◽  
Rat Paw Edema ◽  
Etoac Fraction ◽  
High Antioxidant Activity ◽  
Anti Inflammatory

This study evaluated the antioxidant and anti-inflammatory properties of Marantochloa leucantha (Marantaceae). The in vitro antioxidant activity of the extracts and solvent fractions was evaluated by 1,1-diphenyl- 2-picrylhydrazyl (DPPH) radical scavenging and ferric reducing antioxidant potential (FRAP) assay models and in vivo anti-inflammatory activity by the rat paw edema model. The phytochemical screening indicated the presence of tannins, terpenoids, steroids, flavonoids, reducing sugar and phenolics. The antioxidant assay showed that all the extracts exhibited high antioxidant activity comparable with ascorbic and gallic acid controls. In DPPH model, a 250 μg/ml EtOAc fraction of the leaves showed antioxidant activity of 93.9 ± 1.7 % (EC50 0.82 μg/ml) and a 1000 μg/ml of same stem fraction produced 91.9 ± 0.3 % activity (EC50 1.38 μg/ml). In the FRAP model, EtOAc fraction exhibited 31.1±0.7 and 92.0 ± 2.2 μM Fe2+/g of dried leaves and stem, respectively at 1000 μg/ml FeSO4 equivalent. The anti-inflammatory potential of the plant showed that the crude stem extract and fractions at 200 - 600 mg/kg exhibited significant (p < 0.01) dose-related inhibition of paw edema in rats. A 200 mg/kg EtOAc fraction showed 18.8 % inhibition compared to 31 % observed in diclofenac-treated rats in 2 h post albumin challenge. These findings validated the folkloric use of this plant in the treatment of diseases associated to the oxidative stress and could further provide promising lead compounds with potent antioxidant and anti-inflammatory activities Dhaka Univ. J. Pharm. Sci. 18(2): 233-240, 2019 (December)

Application of Response Surface Methodology to Optimise Preparation High Antioxidant Activity Product from Pinctada fucata Muscle

2011 ◽  
Vol 396-398 ◽  
pp. 1341-1348 ◽  
Author(s):  
Yan Yan Wu ◽  
Lai Hao Li ◽  
Zhen Hua Duan ◽  
Xian Qing Yang ◽  
Jun Shang ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Response Surface Methodology ◽  
Response Surface ◽  
Radical Scavenging ◽  
Response Surfaces ◽  
Pinctada Fucata ◽  
Degree Of Hydrolysis ◽  
Hydrolysis Time ◽  
Activity Product ◽  
High Antioxidant Activity

The high antioxidant activity product was isolated from Pinctada fucata muscle by a method of Alcalase hydrolysis. Optimization using response surface methodology was performed and 3D response surfaces were plotted from the mathematical model. The results indicated that the optimal extraction conditions were as follows: pH 7.0, temperature 61°C, E/S 3.01%, hydrolysis time 3h, under the conditions of hydrolysis products of the DPPH radical scavenging rate of 67.3% and the degree of hydrolysis of 31.2%, which was in good agreement with the predicted model value.

scholarly journals Antioxidant and Chemosensitizing Effects of Flavonoids with Hydroxy and/or Methoxy Groups and Structure-Activity Relationship

2007 ◽  
Vol 10 (4) ◽  
pp. 537 ◽  
Author(s):  
Ju-Mi Jeong ◽  
Cheol-Hee Choi ◽  
Su-Kyeong Kang ◽  
In-Hwa Lee ◽  
Ji-Yoon Lee ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Structure Activity Relationship ◽  
Activity Relationship ◽  
Oh Groups ◽  
Structure Activity ◽  
P Glycoprotein ◽  
Ic50 Values

Purpose. Flavonoids have been used as antioxidant, chemopreventive and chemosensitizing agents. In this study, eleven flavonoids containing a variety of hydroxy (OH) and/or methoxy (OMe) groups were evaluated for their antioxidant, cytotoxic and chemosensitizing effects to create a structure-activity relationship (SAR). Methods. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical solution-based chemical assay and and 2',7'-dichlorofluorescin diacetate (DCFH-DA) cellular-based assay were used to compare the free radical scavenging activity on the same molar concentration basis using the AML-2/DX100 cells which are characterized by the down-regulated expression of catalase and resulting supersensitiviy to hydrogen peroxide. The chemosensitization and cytotoxicity were determined by the MTT assay in the presence or absence of an anticancer drug using the P-glycoprotein-overexpressing AML-2 subline AML-2/D100 cells. Results. The antioxidant activity of the flavonoid (3,5,7,3’,4’-OH) was higher than that of the flavonoid (5,7,3’,4’-OH). Flavonoids substituted with the various number of OMe decreased antioxidant activity. Flavonoids with 7-OH or 5,7-OH groups have the highest cytotoxicity, and flavonoids with 5,7-OMe group intermediate cytotoxicity. The IC50 values of flavonoid (5,7-OMe, 3’,4’,5’-OMe) and flavonoid (5,7-OMe, 4’-OMe), 0.4 M and 1.4 M. The IC50 values of flavonoid (5,6,7-OMe, 3’,4’-OMe) and flavonoid (5,6,7-OMe, 3’,4’,5’-OMe), 3.2 uM and 0.9 M, respectively, and those of flavonoid (5,6,7-OMe, 3’,4’,5’-OMe) and flavonoid (5,7-OMe,3’,4’,5’-OMe) were 0.9 M and 0.4 M, respectively. Conclusions. These results suggest that flavonoids with 3-OH group play a positive role in antioxidant activities, flavonoids with 5-OH and/or 7-OH groups show the higher cytotoxicity, and flavonoids with 3’-OMe and/or 5’-OMe groups plays positive but 6-OMe groups negative roles in the P-glycoprotein (Pgp) inhibition. It is believed that these SAR results can be taken into account for the development of flavonoids with high therapeutic index.

HPTLC analysis and in vitro antioxidant activity of aqueous bark extract of Erythrina variegata L.

2016 ◽  
Vol 63 (3) ◽  
pp. 143-157 ◽  
Author(s):  
Kanakasabapathy Devaki
Keyword(s):  
Antioxidant Activity ◽  
Secondary Metabolites ◽  
High Performance ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Bark Extract ◽  
Erythrina Variegata ◽  
High Antioxidant Activity ◽  
Layer Chromatography

Erythrina variegata L. is an important medicinal plant used in the preparations of Ayurvedic formulations used against several ailments. This study was carried out to investigate the presence of secondary metabolites using phytochemical screening, high-performance thin-layer chromatography (HPTLC) fingerprinting analysis and the antioxidant potential of the aqueous bark extract of E. variegata L. The secondary metabolites and the free radical scavenging activity were analyzed using standard protocols. The results obtained in the present study revealed that E. variegata has high antioxidant activity against free radicals based on phytoconstituents.

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