Development and Validation of an Improved Oxygen Radical Absorbance Capacity Assay Using Fluorescein as the Fluorescent Probe

Ou, Boxin; Hampsch-Woodill, Maureen; Prior, Ronald L.

doi:10.1021/jf010586o

Cited by 2,481 publications

(1,814 citation statements)

References 25 publications

Supporting

Mentioning

1,697

Contrasting

Unclassified

Order By: Relevance

“…This decrease may be due to the steric hindrance created by the saccharides. Our results are similar to those of previous studies [25,34] confirming that quercetin has the greater antioxidant activity of the compounds studied in this paper. …”

Section: Fluorimetric Assaysupporting

confidence: 93%

Study of phenolic compounds as natural antioxidants by a fluorescence method

López

Martínez

Valle

et al. 2003

Talanta

View full text Add to dashboard Cite

Much work has been carried out in recent years on the beneficial effect of phenolic compounds as natural antioxidants which help to neutralize free radicals. In fact, researchers have focused their attention on the pathological role of free radicals in a variety of diseases, among which the most important are atherosclerosis and cancer. Thus, among the components of the so-called 'Mediterranean Diet', phenolic compounds have received increased attention as epidemiological studies have shown that consumption of foods and beverages rich in phenolics is correlated with reduced incidence of heart disease. In this study, four phenolic compounds: (1) 3,4,5-trihydroxybenzoic acid (gallic acid); (2) trans 3,4?,5-trihydroxystilbene (trans -resveratrol); (3) 3,3?,4?,5,7-pentahydroxyflavone (quercetin) and its glycoside (4) 3,3?,4?,5,7-pentahydroxyflavone Á/3-rutinoside (Rutin) have been subjected to antioxidant study by a fluorimetric assay. In this method, the rate of peroxidation induced by 2,2?-azobis (2-methylpropionamidine) dihydrochloride was monitored through the loss of fluorescence of the protein B-phycoerythrin (B-PE). Under appropriate conditions, the loss of B-PE fluorescence in the presence of reactive species is an index of oxidative damage of the protein. The inhibition of the action of reactive species by phenolic compounds, reflected in the protection against the loss of B-PE fluorescence in the fluorimetric assay, is a measure of its antioxidant capacity against the reactive species. The antioxidant effects of phenolic compounds have been investigated at different concentrations to relate activity to structural effects. It has been observed that the fluorescence decay due to peroxyl radical attack on B-PE decreases exponentially with time. As a reference compound for antioxidant capacity we used 6-hydroxy-2,5,7,8-tetramethyl-chroman-2-carboxylicacid (trolox), a water soluble tocopherol analogue. This compound reacts rapidly with peroxyl radicals, and, until the trolox is consumed, no loss in phycoerythrin fluorescence is observed. A linear correlation of the net protection value with the concentration of trolox was demonstrated. The phenolic compounds studied react with peroxyl radicals in a similar way to trolox. Quercetin and rutin were shown to have strong antioxidant activities. The results obtained here are in agreement with previous studies confirming that quercetin is the most antioxidant of the four polyphenolics. #

show abstract

Section: Fluorimetric Assaysupporting

confidence: 93%

Study of phenolic compounds as natural antioxidants by a fluorescence method

López

Martínez

Valle

et al. 2003

Talanta

View full text Add to dashboard Cite

show abstract

“…Cell viability was determined using an MTT assay 29. Various concentrations of sesamol, arbutin or PTU were added to the cells and incubated for 24 h. Next, 100 μ l of MTT solution (5 mg/ml MTT in PBS) was added to each well, followed by incubation at 37°C for 1 h. After removal of the MTT solution, 1 ml of dimethyl sulfoxide was added to each well with vigorous mixing.…”

Section: Methodsmentioning

confidence: 99%

Sesamol decreases melanin biosynthesis in melanocyte cells and zebrafish: Possible involvement of MITF via the intracellular cAMP and p38/JNK signalling pathways

Baek

Lee

2015

Experimental Dermatology

View full text Add to dashboard Cite

The development of antimelanogenic agents is important for the prevention of serious aesthetic problems such as melasma, freckles, age spots and chloasma. The aim of this study was to investigate the antimelanogenic effect of sesamol, an active lignan isolated from Sesamum indicum, in melan‐a cells. Sesamol strongly inhibited melanin biosynthesis and the activity of intracellular tyrosinase by decreasing cyclic adenosine monophosphate (cAMP) accumulation. Sesamol significantly decreased the expression of melanogenesis‐related genes, such as tyrosinase, tyrosinase‐related protein‐1,2 (TRP‐1,2), microphthalmia‐associated transcription factor (MITF) and melanocortin 1 receptor (MC1R). In addition, sesamol also induces phosphorylation of p38 mitogen‐activated protein kinase (p38 MAPK) and c‐Jun N‐terminal kinase (JNK). Moreover, sesamol dose‐dependently decreased zebrafish pigment formation, tyrosinase activity and expression of melanogenesis‐related genes. These findings indicate that sesamol inhibited melanin biosynthesis by down‐regulating tyrosinase activity and melanin production via regulation of gene expression of melanogenesis‐related proteins through modulation of MITF activity, which promoted phosphorylation of p38 and JNK in melan‐a cells. Together, these results suggest that sesamol strongly inhibits melanin biosynthesis, and therefore, sesamol represents a new skin‐whitening agent for use in cosmetics.

show abstract

“…In general, the methods were divided into two major groups: Assays based on a single electron transfer (SET) reaction, with a change in color as the oxidant is reduced, and assays based on a hydrogen atom transfer (HAT) (Huang et al, 2005), which measures the activity of the antioxidant to scavenge the peroxyl radicals, such as, the total radical trapping antioxidant parameter (TRAP) assay, the oxygen radical absorbance capacity (ORAC) assay, and the luminol-chemiluminescence-based peroxyl radical scavenging capacity (LPSC) assay (Alho and Leinonen, 1999;Huang et al, 2005;Ou et al, 2001). The assays electron transfer includes the reaction of ferric reduction (FRAP), the α-tocopherol/Trolox equivalent antioxidant capacity (TEAC), and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) (Benzie and Strain, 1996;Brand-Williams et al, 1995;Huang et al, 2005;Re et al, 1999).…”

Section: Introductionmentioning

confidence: 99%

Contents of constituents and antioxidant activity of seed and pulp extracts of Annona coriacea and Annona sylvatica

et al. 2015

View full text Add to dashboard Cite

The antioxidant potential of fruit pulp and seeds of extracts of the Annona coriacea, and A. sylvatica (Annonaceae) were investigated, as well contents total phenolics, flavonoids, condensed tannins and ascorbic acid. Was used to determine the antioxidant activity the 1,1-diphenyl-1-picrylhydrazyl free radical (DPPH), β-carotene bleaching and ABTS radical cation method. The total phenol, total flavonoid, condensed tannin, and ascorbic acid contents were measured spectrophotometrically. In this study, the pulp and seeds of the fruits were extracted using methanol/water (8:2) for maceration. The seed extracts of A. coriacea demonstrated a moderate antioxidant effect with free radical scavenging activity of 31.53%, by the DPPH test, 51.59% by the β-carotene bleaching test and 159.50 µM trolx/g of extract in the ABTS assay. We found that the hydromethanolic seed extract of A. coriacea had high total phenol (147.08 ± 4.20 mg of GAE/g of extract) and flavonoid (131.18 ± 2.31 mg of QE/g of extract) content. This indicated that the antioxidant activity of the extracts was related to the contents of these constituents.Keywords: Annona, antioxidant activity, phytochemistry. Conteúdo

show abstract

Development and Validation of an Improved Oxygen Radical Absorbance Capacity Assay Using Fluorescein as the Fluorescent Probe

Cited by 2,481 publications

References 25 publications

Study of phenolic compounds as natural antioxidants by a fluorescence method

Study of phenolic compounds as natural antioxidants by a fluorescence method

Sesamol decreases melanin biosynthesis in melanocyte cells and zebrafish: Possible involvement of MITF via the intracellular cAMP and p38/JNK signalling pathways

Contents of constituents and antioxidant activity of seed and pulp extracts of Annona coriacea and Annona sylvatica

Contact Info

Product

Resources

About