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Not Really About Hemicellulose The Cole-Fort Research Group. Want to Live to Be 140?. Start with calorie restriction (CR): Calorie restriction means a low calorie diet containing all necessary nutrients CR extends the life of C. elegans , Drosophila, mice, and some primates
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Not Really About Hemicellulose The Cole-Fort Research Group
Want to Live to Be 140? • Start with calorie restriction (CR): • Calorie restriction means a low calorie diet containing all necessary nutrients • CR extends the life of C. elegans, Drosophila, mice, and some primates • Good health is maintained • Resveratrol • Found in red wine (pg/mL) • Claimed to be responsible for the “French paradox” • Mimics the effect of calorie restriction
OK, you’re a fat mouse, and we feed you resveratrol: • Insulin sensitivity increases • Insulin-like growth factor (IGF-1) decreases • Peroxisomeproliferator increases • Motor function improves • Alzheimer’s peptide decreases • Result: • No type II diabetes • Reduced risk of cancer • Lower blood lipids • You make the mouse Olympics More: http://chemistry.umeche.maine.edu/CHY431/Resveratrol.html
So we went out in the woods, cut down a bunch of trees, stripped the bark, and made conifer bark tea • Grind up the bark • Place in the cup of a Soxhlet extractor • Boil alcohol and water in the bottom • Go home for 24 hours
Why the bark? Conifers store antioxidants in the bark to guard against fungi and bark beetles Fungi use oxidative enzymes (laccase, peroxidase) to degrade bark; beetles attack partially degraded bark
Our work with formaldehyde, starts here: Katrina and the infamous FEMA trailers
Raw (untreated) wood emits formaldehyde, at room temperature and above!
Trapped as 2,4,6-trichlorophenylhydrazide, gc-ms+sim analysis ppm formaldehyde, by mass, oven dried wood
Most formaldehyde comes from lignin. How? ppm by mass, air-dried material
Enzymatic Hydrolysis of Xylans and Cellulose • The goal is to convert these wood components to sugars under mild conditions • Immobilization of enzymes on polymer beads would make the enzymatic processes more economical • Immobilization also would allow a continuous flow process, rather than batch processing
Multiple Enzymes Will Be Required Xylanase α-Glucuronidase
Hydrolysis of Birch Xylan with the Xylanase from TrichodermaViride Homology model of T. viridexylanase, based on xylanase from T. reesei
Computer “Docking” of a Model Substrate Glu178 Glutamic Acid Glu86
Hydrolysis of Birch Xylan 4% Sulfuric Acid, 119 oC
Enzymatic Hydrolysis, pH 4.5, 35 oC Hardwood hemis hydrolyzed in “green liquor”
Enzymes Homology model of glucohydrolase from Aspergillusniger Glucohydrolase from Trichodermareesei
Lignin-related Molecules Tested As Inhibitors Vanillin Acetovanillone Vanillic Acid p-Coumaric Acid
Inhibitors were evaluated by classical enzyme kinetics, using the Lineweaver-Burke technique Km, the binding constant, and kcat, the turnover number can be determined from these plots
Results of Kinetic Studies For the enzyme from A. niger, the inhibitors tested had no effect within experimental error The enzyme from T. reesei did suffer inhibition of the order of 30-35% with some materials; for example, vanillic acid We now are conducting computational docking studies to explore the mode of interaction of the inhibitors with the enzymes
Example Docking p-Coumaric acid docked to A. nigerenzyme Cellobiose (substrate) docked to T. versicolor enzyme
FormaldehydeResveratrol Ashley Hellenbrand (MS) Regan LeBlanc (MS) Hannah Cole (OHS) Melody Rhine (REU) Anna Weigang UM Dustin Neidt (BS) Andria Peña-Melendez (REU) PandukaPiyaratne Joel Strothers (REU) Enzymatic Hydrolysis LeRae Graham (PhD) GaminiRupasinghe (MS) Francis and Robin Avery, Brian Perkins $$ USDA, NSF-EPSCoR, WBC, FBRI Prof. Barbara Cole Prof. Joe Genco Prof. Ray Fort
Extra: How does Resveratrol Work?