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Dietary Antioxidant. A substance in foods that significantly decreases the adverse effects of reactive species, such as reactive oxygen (ROS) and nitrogen species, on normal physiological function in humans. Some antioxidants in foods. vitamin C. vitamin E. carotenoids. glucosinolates.
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Dietary Antioxidant A substance in foods that significantly decreases the adverse effects of reactive species, such as reactive oxygen (ROS) and nitrogen species, on normal physiological function in humans.
Some antioxidants in foods vitamin C vitamin E carotenoids glucosinolates polyphenols flavonoids catechins isoflavones phenolic acids… …
Tyrosinase O2 Electrode Tyr 2 e- H2O2 x mV/AgAgCl Tyr : tyrosinase (EC 1.14.18.1) or monophenol monooxygenase Tyrosinase from mushroom (SIGMA) Calibration : Substrat : 1,2-benzenediol = catechol Catechol Equivalent (CE) 1-Biosensors for the detection of polyphenols tyrosinase (EC 1.10.3.1) or catechol oxidase tyrosinase from a plant source Amorphophallus companulatus
Determination of the reduction potential of benzoquinone Scan rate : 50 mV/s
Calibration curve Linear range : 0,1 60 µM Sensitivity : 166 mA.M-1 Limit of Detection : 6.10-2 µM
µmol CE /g product % weight 100% 0.097 74% 0.0334 0.657 4.5% 0.193 21.5% 0.096 Real samples : Grapes Pulp Seeds Skin
O OH 1,4-benzenediol… Laccase O2 Electrode Lac 2 e- H2O2 x mV/AgAgCl Lac : Laccase (EC 1.10.3.2)or Urishiol oxidase Calibration : substrats : 1,2-benzenediol
Electrode H2O2 SOD 2 e- 2H+ Oxidation response XOD : xanthine oxidase (EC 1.1.3.22) SOD ANTIOX : superoxide dismutase (EC 1.15.1.1) 2-Biosensor for the determination of an antioxidant capacity O2• - Xanthine XOD O2 Uric Acid
Sample line (antioxidant) Mixing section Detection chamber SOD-based biosensor Lab-on-a-chip ROS generation chamber Water TiO2 nanoparticule UV light