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The Sensational Science Behind Antioxidants: Testing Facts vs. Myths of popular antioxidant products. Yesterday, you broke up into groups and selected a popular “antioxidant-rich” product to endorse. Today you will chemically test the drinks to see if there’s truth to their marketing. .
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The Sensational Science Behind Antioxidants: Testing Facts vs. Myths of popular antioxidant products
Yesterday, you broke up into groups and selected a popular “antioxidant-rich” product to endorse Today you will chemically test the drinks to see if there’s truth to their marketing. You are the Research & Development Team and the Marketing Team for your product.
Part I: The science behind antioxidants Free radicals cause damage by oxidation Free radical with unpaired electron Victims of Oxidation
O O Add 1ste- Add 2nde- Peroxide radical O2-2 Superoxide radical O2- Molecular Oxygen O2 Add two H+ Reactive Oxygen Species ROS H O O O O O O O H Water Hydrogen peroxide H2O2 H H O O H H Add 2H+ Add 3rde- H H O O H Hydroxyl radical OH Add 4the- Hydroxyl ion OH- Hydroxyl ion OH-
Free radicals cause damage by oxidation Oxidation occurs when one substance transfers one or more its electrons to another substance Electrons lost to + H2O + ½O2 Catechol Colorless Benzoquinone Yellow-Brown “Catechol is oxidized by O2to become benzoquinone” “Catechol loses its electrons to O2to become benzoquinone”
Phenol Oxidase catalyzes the reaction that changes catechol, in the presence of O2, into benzoquinone Phenol Oxidase + H2O + ½O2 Catechol Colorless Benzoquinone Yellow-Brown
Phenol Oxidase catalyzes the reaction that changes catechol, in the presence of O2, into benzoquinone Phenol Oxidase X + H2O + ½O2 + Antioxidant! Catechol Colorless Benzoquinone Yellow-Brown
Phenol Oxidase catalyzes the reaction that changes catechol, in the presence of O2, into benzoquinone Phenol Oxidase + H2O + ½O2 Catechol Colorless Benzoquinone Yellow-Brown
Can any of these products inhibit the browning reaction in mushrooms? x 10 Controls: Buffer pH 7 100X Daily Dose of Vitamin C
2. Chop mushroom into pieces and put into Ziploc bag 3. Close bag tightly and mash gently with fingers Purifying mushroom oxidase 1. Weigh mushroom Multiply mass by 4 and add that amount of buffer to the bag Perform the tests! 4. Wet the coffee filter with buffer and place over cup. Use pipette to transfer mushroom extract to filter
Spot test Time = 0 min • Using the pipette, add two drops of mushroom oxidase to every square on your table. • Add the appropriate reactants to each square in the order they are listed • Once all the drops have been added to the 6 squares, start the timer. • Observe the reaction for5 minutes, then answer the following questions. Hint: Use a steady hand so that each drop is the same amount of liquid. Make sure the paper is level, so the drops do not move. Time = 5 min
Double bonds absorb light http://science-edu.larc.nasa.gov/EDDOCS/Wavelengths_for_Colors.html
How does a spectrophotometer work? 0.430 Absorbance Readout At Abs490 nm: Wavelength selector + H2O + ½O2 Prism to disperse light Light Catechol Colorless Benzoquinone Yellow-Brown 0.240 0.520
Spectrophotometer Test • Label your test tubes #2, #4, #6 and buffer blank • Add 4 ml of buffer to “buffer blank”. Place the tube into spectrophotometer holder and use the left knob to set the numbers in the absorbance window to 0.000. • Add the reactants for Tube #2—use correct pipettes for each reactant! Mix by tapping the test tube, and place tube into spectrophotometer. Start the timer and record absorbance at t=0 min. • Remove tube at t = 4:30 min and mix by tapping test tube. Record absorbance at t= 5 min. • Repeat steps 3-4 for each Tubes #4, #6.
There are many different ways to test for antioxidants Our mushroom oxidase test may not be sensitive enough to pick up on antioxidant levels
Phenol Oxidase X + H2O + ½O2 + Antioxidant! Catechol Colorless Benzoquinone Yellow-Brown
Phenol Oxidase X + H2O + ½O2 + Antioxidant! Catechol Colorless Benzoquinone Yellow-Brown Your drink has antioxidants, but it may be very low amounts compared to 100X Daily Value of Vitamin C
Present a 3 minute marketing campaign that showcases: • Your knowledge on the mechanism and health benefits of antioxidants defense against free radicals. • Your product’s antioxidant test results. • Your opinion why your classmates should buy your antioxidant drink.
(Instructor note: show a video clip of antioxidants in the media. In my presentation, I edited together a video of 9 different commercials, interviews on the topic of antioxidants) Edited by Ms. Theresa
Do not make scientific claims that you cannot back with evidence Find a different approach to market the product
Much research has to be performed before claims can be made “I recommend pizza since it is a vegetable and therefore has *tons* of antioxidants.” I’m actually a real doctor! Google me!
Sample Ballot Which product is the best antioxidant drink on the market? The best scientific argument was made by: The best marketing campaign was for: ☐7-Up Antioxidant ☐ Activate Antioxidants ☐ FUZE Triple Berry ☐ Lipton Green Tea ☐ POM Wonderful ☐ Vitamin Water XXX ☐ Other ___________ ☐ 7-Up Antioxidant ☐ Activate Antioxidants ☐ FUZE Triple Berry ☐ Lipton Green Tea ☐ POM Wonderful ☐ Vitamin Water XXX ☐ Other ___________ Write-in: Based on the overall campaign and facts, I would consider buying: