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Ethnobotany. Lecture 15
Alexey Shipunov
Minot State University
February 25, 2015
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 1 / 27
Outline
1 Centers of cultivated plants origin
2 Sugar plantsSugarsSweeteners
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 2 / 27
Outline
1 Centers of cultivated plants origin
2 Sugar plantsSugarsSweeteners
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 2 / 27
Centers of cultivated plants origin
Harlan’s centers of agricultural beginnings
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 3 / 27
Sugar plants Sugars
Sugar plantsSugars
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 4 / 27
Sugar plants Sugars
Ethanol
Immediate product of yeast fermentation of glucosePre-adaptation to alcohol from frugivoresBind to GABA (gamma-aminobutyric acid) receptorsConverted into acetaldehyde (toxic!) by alcohol dehydrogenaseand then into acetic acid by acetaldehyde dehydrogenase“Asian flush” (result of acetaldehyde dehydrogenase deficiency)and alcoholism are related to the genetic diversity of alcoholdehydrogenases
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 5 / 27
Sugar plants Sugars
Downsides of sugars
Obesity, because sugars are easily convert into fatsDiabetes, because insulin cannot deal with large quantities ofsugarsDental diseases, especially dental caries (caused by lactobacteriataking sugars for their growth)Multiple sweeteners have been developed to avoid side-effects ofsugars: heterocyclic saccharine (in “Sweet’N Low”), amino acidderivative aspartame (in “Equal”), chlorine hexose sucralose (in“Splenda”, “Altern”). All are controversial.
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 6 / 27
Sugar plants Sweeteners
Sugar plantsSweeteners
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 7 / 27
Sugar plants Sweeteners
Stevia rebauldiana, the natural sweetener
Belongs to aster family, CompositaeOriginated in South AmericaLeaves contain the group of sweet glycosides, derivatives ofsteviolThey are 100–150 times sweeter than sucrose (on the weightconcentration basis)Despite of multiple controversies (not approved in EU, banned inNorway and Singapore) used by Coca-Cola and PepsiCo in their“zero calories” drinks
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 8 / 27
Sugar plants Sweeteners
Stevia flowers
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 9 / 27
Sugar plants Sweeteners
Steviol
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 10 / 27
Sugar plants Sweeteners
Our native natural sweeteners
North Dakotan wild licorice (Glycyrrhiza lepidota) belongs tolegume family, LeguminosaeContains natural sweetener glycyrrhizin, about 50 time sweeterthan sucroseSide-effects are hypertension and lowering of testosterone level inmales
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 11 / 27
Sugar plants Sweeteners
American licorice, Glycyrrhiza lepidota
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 12 / 27
Sugar plants Sweeteners
Glycyrrhizin
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 13 / 27
Sugar plants Sweeteners
What is sweetness?
Nature of sweetness is not yet fully discoveredProbably due to specific Van der Waals forces occurring in varietyof moleculesThese molecules have an effect on sweet receptors—largeproteins from G protein-coupled receptors (GPCRs) group
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 14 / 27
Sugar plants Sweeteners
GPCR, sweetness receptor
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 15 / 27
Sugar plants Sweeteners
Miracle fruit, Synsepalum dulcificum, thesuper-sweetener
West African tree, belongs to tropical Sapotaceae familyBerries convert sour tastes into sweet tastes (!), effect lasts for ≈1hourThe effect is due to glycoprotein miraculin which is binding tosweet receptorsCultivation is now starting in Florida, approval as food additive ispending—it is heat-resistant and may be used as a “sweetener”;there are genetically modified lettuce plants which producemiraculin
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 16 / 27
Sugar plants Sweeteners
Miracle fruit
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 17 / 27
Sugar plants Sweeteners
Miraculin glycoprotein
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 18 / 27
Sugar plants Sweeteners
Other plants super-sweeteners
Curculin from Curculigo latifolia (“lumbah-lumbah”), Malaysianherb from Hypoxidaceae family, has the same effect + it is alsosuper-sweet by itself (500–2000 times sweeter on weight basisthan sucrose).Thaumatin from Thaumatococcus daniellii (“miracle berry”), WestAfrican herb from Marantaceae, is 3000 times sweeter thansucrose.Monellin from Dioscoreophyllum volkensii (“serendipity berry”),West African Menispermaceae vine, is 800–2000 times sweeterthan sucrose but only to Old World monkeys including humans.
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 19 / 27
Sugar plants Sweeteners
Lumbah-lumbah
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 20 / 27
Sugar plants Sweeteners
Miracle berry (not “miracle fruit”!)
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 21 / 27
Sugar plants Sweeteners
Thaumatin, the most sweet protein
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 22 / 27
Sugar plants Sweeteners
Anti-sweeteners
Several plants contain chemicals which are able to suppresssweet receptorsIndian herbaceous vine Gymnema sylvestris from a dogbanefamily (Apocynaceae) contain gymnemic acids which suppresssweet taste for ≈10 minIn addition, plant has an unrelated (?) effect in lowering bloodsugarsUsed as a drug for curing Type 2 diabetes and different forms ofmetabolic disorders
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 23 / 27
Sugar plants Sweeteners
Gymnema sylvestre
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 24 / 27
Sugar plants Sweeteners
Gymnemic acid
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 25 / 27
Sugar plants Sweeteners
Summary
Sugar is highly used but controversial source of energySweet taste still has undiscovered nature
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 26 / 27
Sugar plants Sweeteners
For Further Reading
A. Shipunov.Ethnobotany [Electronic resource].2011—onwards.Mode of access:http://ashipunov.info/shipunov/school/biol_310
P. M. Zhukovskij.Cultivated plants and their wild relatives [Electronic resource].Commonwealth Agricultural Bureaux, 1962. Abridged translationfrom Russian.Mode of access:http://ashipunov.info/shipunov/school/biol_310/zhukovskij1962_cultivated_plants.djvu.
Shipunov (MSU) Ethnobotany. Lecture 15 February 25, 2015 27 / 27