Tìm thấy 20+ kết quả cho từ khóa "Free radical scavenging"
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Additionally, olive seed lignin antioxidant capacity was calculated by evaluating free radical scavenging effect against DPPH free radical according to the earlier methods [6]with slight modifications. of olive seed lignin was calculated from the data of DPPH inhibition using UV-Vis spectra. where AA% is the antioxidant activity, A o is the absorbance of the control and A s is the absorbance of lignin sample..
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DPPH Radical Scavenging Assay. extracts were diluted into tested concentrations (0.02 and 0.1 mg/ml). Free Radical Scavenging Activity. The free radical scavenging activity of ethanolic extracts of investigated plants are shown in Figure 1. Among the extracts, the mixture of ginger and kumquat possessed the highest activity (32% and 85% at the concentration of 0.02 and 0.1 mg/ml, respectively).
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The rambutan peel extract exhibited higher antioxidant activity than seed extracts [18], rambutan peel possessed high DPPH free radical scavenging activity (IC 50 of 8.87 μg/ml) [19], high polyphenols content of rambutan peel contributes towards high free radical scavenging activity [20].
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The ethyl acetate fraction had the highest total phenolic content mg GAE/g) and total flavonoid content mg QE/g). collinsae root fractions showed moderate antioxidant activity through DPPH free radical scavenging activity. Among fractions, ethyl acetate fraction exhibited strongest DPPH free radical scavenging activity (IC μg/mL).. Antiviral and anticancer activities of Stemona collinsae. Occurrence of the insecticidal 16, 17-didehydro-16 (E)-stemofoline in Stemona collinsae.
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Additionally, compounds 5a–5h were also evaluated for antioxidant potential using DPPH free radical scavenging and ferric thiocyanate (FTC) assays. The structure elucidation of the synthesized compounds was carried out by UV-Vis, FT-IR, 1 H NMR, 13 C NMR, and elemental analysis and mass spectrometry.
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The DPPH method is commonly used for determination of free radical scavenging activity of antioxidant. For both variety Gemiza-9 and Beni-suef-3 extracts, bran samples showed strong DPPH free radical scavenging activities and respectively). These results were supported by those of Liyana-Pathiran and Shahidi (2007) who found that the ability to scavenge DPPH radicals in wheat fractions was in the order of bran >. In addi- tion, it can be seen that the solvent systems used affected the.
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Assays for total phenolic contents and DPPH radical scavenging activity. A comparative study on the antioxidant properties of WGO and BCSO was performed. The antioxidant capacity of seed oil extracts was determined by evaluating total phenolic contents and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity..
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In this work, we used the DPPH free radical scavenging method to evaluate the antioxidant potential of the synthesized Pc compounds. The descending order of radical scavenging activity of the tested Pc compounds was 6 >. The Pc compounds showed lower DPPH activity in comparison to the known Trolox and BHT standards (Figure 1). The DPPH scavenging activities of metal-free Pc compounds were also measured.
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The free radical scavenging activity of the essential oils, based on the scavenging activity of the stable 1,1-diphenyl-2- picrylhydrazyl (DPPH) free radical was determined by the method described by Zou et al. The absorbance of the mixture was measured spectrophotometrically at 517 nm. where A 0 is the absorbance of the control (containing all reagents except the test compounds), and A 1 is the absorbance of the oils/standard.
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DPPH free radical scavenging activity. The free radical scavenging activity of the samples was determined by the DPPH assay. Determination of the antioxidant activity with the β -carotene bleaching method. Measurement of superoxide anion radical scavenging activity of the samples was based on the standard method with slight modification. The ferric reducing power of the samples was determined according to the iron(III) reductive assay.
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DPPH scavenging activities of the tested compounds also represent free radical scavenging activities. The ABTS radical scavenging activities of the tested compounds are summarized in Table 4 as percentage inhibition rate. ABTS radical scavenging activities of thiosemicarbazones were significantly higher compared to nickel(II) complexes..
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Therefore, we selected 30 by-products casually to investigate their antioxidant activity by using different antioxidant tests, including DPPH free radical scavenging assay, Ferric reducing/antioxidant power (FRAP) assay and determination of total phenolics contents.
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The free radical scavenging capacities of the compounds were also tested in vitro determining the interaction of the stable free radical 2,2,diphenyl- 1-picrylhydrazyl (DPPH), and compounds 4a and 4b exhibited good antioxidant activities.. Impair- ment of the antioxidants and antioxidant systems could be related to increased oxidative stress.
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In Vitro evaluation of the antioxidant activity of aqueous, hydroethanolic and hexane extracts of Spathodea campanulata Free Radical Scavenging Activity. Hydrogen atom or electron donating abilities of the compounds were measured from the bleaching of the purple-colored methanol solution of 2,2-diphenyl-1-picryl hydrazyl (DPPH). This spectrophotometric assay uses the stable free radical, DPPH as a reagent (Parejo et al., 2000)..
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The free radical scavenging activity of the extracts and the isolates from H. Determination of the antioxidant activity with the β -carotene bleaching method. The antioxidant activity of the extracts and isolates from H. Anticholinesterase activity. This study was a part of the master thesis of D
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Different reaction mechanisms with power reduction for CUPRAC and free radical scavenging operation for DPPH lead to this phenomenon (Singh et al., 2019). The ability of an- tioxidants varied between the different cardamom accessions and can be explained by the different forms or contents of components of anti- oxidants within (Donno et al., 2015).. The antioxidant activity of cardamom accessions determined against CUPRAC is presented in Table 2.
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Antioxidant activity assessment was carried out using two methods: scavenging ability of naphthoxazoles and fused heterobenzoxazoles towards both DPPH� and FRAP.. DPPH scavenging ability of the samples was measured according to a recently reported procedure. 33 The results for the free radical scavenging activities of the samples are expressed as IC 50 values (where possible) and inhibition percentages of DPPH radical.
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In this study, we examined the mechanisms of the free radical scavenging action of HBAs and their anions using density functional theory (DFT) methods. For anions of HBAs, HAT and SPLET mechanisms in pentylethanoate are competitive, while SPLET is the most probable pathway in the case of HBAs..
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In the current investigation, CDFP-extract appeared promising an- tioxidant characters as free radical scavenging, ROS scavenging, Fe +3 reduction capacity, and Fe +2 chelation activity. CDFP-extract exhibited anti-tumor activity as a reduction of proliferation, induction of apop- tosis appeared in the increasing non-viable tumor cell, prolongation life span, and amelioration hematological parameters.
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Amic et al., 2003), and include: (i) direct free radical scavenging, (ii) chelation with transition metal ions, and (iii) inhibition of enzymes,. Phenolic compounds (PheOH) inactivate free radicals via hydrogen atom transfers (reaction 1) or single electron transfers (reaction 2) (Leopoldini et al., 2011):. and the lack of suitable sites for attack by molecular oxygen (Leopoldini et al., 2011).