Free Radical

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Free Radical

O 2.RO .NO .O 2.NO . O 2.RO .NO .


Free RadicalBenefit* Antimicrobial system-Activated granulocytes


Antioxidant ScreeningSpray Reagent0.2% DPPH in Ethanol0.05% beta-carotene


0.2% DPPH in EthanolResultpale yellow on the violet background.0.05% beta-carotene in CHCl 3MethodBleaching in UV 254 until background discolor


DPPH METHOD• 6*10-5 M DPPH(1,1-diphynyl-2-picryhydrazyl)• Sample• 1:1• incubate 15-30 min• λ 515 nmControl• Trolox• Vitamin C• BHT• BHA


ABTS• 7mM ABTS + 2.45 mM potassium persulphate(2,2’-azinobisazinobis-[3ethylbenzthiazoline-6-sulphonic acid])incubate 12-16 16 h• 5 mM phosphate buffer (pH 7.4)• 10 ul sample• 4 ml ABTS +• λ 730 nm• kinetic 20-30 s 6 min


NO TestNO + O 2 NO 2 +NO 3• 10 mM Sodium nitroprusside in 20 mM Phosphatebuffer (pH 7.4)• Sample in 20 mM Phosphate buffer (pH 7.4)• incubate 150 min, Temp. 25 C• λ 542 nm


eta- carotene• beta-carotene + linoleic acid + tween 40• Sampleλ • 470 nm• Kinetic 0-1800min, time 10 min


Ferric Reducing Antioxidant PowerFe(III) Fe(II)• 300 mM acetate buffer (pH 3.6)• 20 mM Ferric chloride• 10 mM 2,4,6-tripyridyltripyridyl-s-triazine triazine in 40 mM HCl• 25:2.5:2.5Ferrous- tripyridyltriazine


Ferric Reducing Antioxidant PowerFRAP reagent 3 ml+ sample 40 ulincubate 37 C, 90 minλ 593 nm* low pH


Mo assayMo(VI) Mo(V)• Standard curve :Vitamin C or Gallic acid• 0.6 M H 2 SO 4• 28 mM Sodium phosphate• 4 mM Ammonium molybdate


Mo assayMo reagent 3 ml + Sample 0.3 mlλ 695 nmincubate 90 minTemp. 95C


Total Flavonoids• Rutin standard1 ml sample(10g/l)+1ml AlCl 3 (20g/l)+25 ml ethanolincubate 40 minTemp. 20 Cλ 415 nm

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