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How do you store a DPPH in methanol solution for long term purpose?
Bhagyamendis
you should not store DPPH for longer than a day as it degrades rapidly. But I would guess that a glass bottle should suffice
Wiki User
∙ 11y ago
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How do you prepare dpph radical solution?
it has to be prepared using methanol or ethanol at the concentration we required.
How do you prepare 1 mM dpph radical solution?
for prepare 1mM DPPH radical solution: DPPH Molecular weight: C18H12N5O6 = 394g DPPH 1mM = 394/1000= 0.394g/L
How do you prepare0.1m dpph solUTION?
1mM DPPH (MW 394.32) solution would be 0.39 mg/1mL 1M = 390 mg/1mL
How do you prepare 0.2 milli molar DPPH solution in ethanol?
Dissolve 0,788 g DPPH in 1L ethanol.
How do you prepare 300 mM dpph radical solution?
I really dont know people
What are the reagents used in the estimation of antioxidants?
There are various reagents that are used in the estimation of antioxidants. Folin-Ciocalteu and DPPH are the most common reagents used in determining antioxidant activity.?æ
How do you calculate ic50 for antioxidant activity?
Scavenging capacity (%) = 100 - [(absorbance of sample - absorbance of blank) × 100/absorbance of control] The tests were done in triplicate. The IC50 values were calculated by linear regression of plots, where the abscissa represents the concentration of the tested plant extracts and the ordinate the average percent of scavenging capacity. The concentration of sample required to scavenge 50% of DPPH (IC50) were determined.
What is the solute for syrup?
For corn syrup: it is fructose and glucose - C6H12O6Canadian maple syrup: Twenty-three phenolic compounds were isolated from a butanol extract of Canadian maple syrup (MS-BuOH) using chromatographic methods. The compounds were identified from their nuclear magnetic resonance and mass spectral data as 7 lignans [lyoniresinol (1), secoisolariciresinol (2), dehydroconiferyl alcohol (3), 5′-methoxy-dehydroconiferyl alcohol (4), erythro-guaiacylglycerol-β-O-4′-coniferyl alcohol (5), erythro-guaiacylglycerol-β-O-4′-dihydroconiferyl alcohol (6), and [3-[4-[(6-deoxy-α-l-mannopyranosyl)oxy]-3-methoxyphenyl]methyl]-5-(3,4-dimethoxyphenyl)dihydro-3-hydroxy-4-(hydroxymethyl)-2(3H)-furanone (7)], 2 coumarins [scopoletin (8) and fraxetin (9)], a stilbene [(E)-3,3′-dimethoxy-4,4′-dihydroxystilbene (10)], and 13 phenolic derivatives [2-hydroxy-3′,4′-dihydroxyacetophenone (11), 1-(2,3,4-trihydroxy-5-methylphenyl)ethanone (12), 2,4,5-trihydroxyacetophenone (13), catechaldehyde (14), vanillin (15), syringaldehyde (16), gallic acid (17), trimethyl gallic acid methyl ester (18), syringic acid (19), syringenin (20), (E)-coniferol (21), C-veratroylglycol (22), and catechol (23)]. The antioxidant activities of MS-BuOH (IC50 > 1000 μg/mL), pure compounds, vitamin C (IC50 = 58 μM), and a synthetic commercial antioxidant, butylated hydroxytoluene (IC50 = 2651 μM), were evaluated in the diphenylpicrylhydrazyl (DPPH) radical scavenging assay. Among the isolates, the phenolic derivatives and coumarins showed superior antioxidant activity (IC50 < 100 μM) compared to the lignans and stilbene (IC50 > 100 μM). Also, this is the first report of 16 of these 23 phenolics, that is, compounds 1, 2, 4−14, 18, 20, and 22, in maple syrup.
Isolated chemical compound of adansonia digitata?
Besides (-)-epicatechin, epicatechin-(4β-8)-epicatechin (procyanidin B2), epicatechin-(4β-6)-epicatechin (procyanidin B5), epicatechin-(4β-8, 2β-O-7)-epicatechin (proanthocyanidin A2) and epicatechin-(4β-8)-epicatechin-(4β-8)-epicatechin (procyanidin C1), which were isolated before from Adansonia digitata [1], in this work an A-type proanthocyanidin trimer, i.e. epicatechin-(4β-8)-epicatechin-(4β-8, 2β-O-7)-epicatechin, tetrameric procyanidin D1, i.e. epicatechin-(4β-8)-epicatechin-(4β-8)-epicatechin-(4β-8)-epicatechin and a polymeric compound were isolated from the pericarp (fruit wall) of the fruits for the first time from this plant [2]. The antioxidant activity of different fractions and pure compounds was experimentally evaluated in the DPPH· assay. The ethyl acetate fraction, and most of the isolated compounds displayed a high activity (IC50 2.40-9.60µg/ml) compared with the reference antioxidant [3] Trolox (IC50 12.18µg/ml) as a standard.Acknowledgements: University of Antwerp Belgium, Prof. Dr. Pieters L. and Prof. Dr. Apers S. for NMR and MS spectra measurements.References: 1. Escribano-Bailon, T., et al. (1992)J. Agric. Food Chem. 40: 1794-1799.2. Esterhuyse, N. et al. (2001) Remarkable Trees of South Africa. Briza Publications, Pretoria.3. Cos, P. et al. (2002). Free Rad. Res. 36: 711-716.
