NATURAL POLYMERS MU SCI 4 2018 1 NATURAL POLYMERS 4 Plant (vegetable) GUMS Dr. Ladislav Pospíšil 29716@mail.muni.cz January 2018/4 Time schedule January 2018/4 NATURAL POLYMERS MU SCI 4 2018 2 LECTURE SUBJECT 1 Introduction to the subject – Structure & Terminology of nature polymers, literature 2 Derivatives of acids – natural resins, drying oils, shellac 3 Waxes 4 Plant (vegetable) gums, Polyterpene – natural rubber (extracting, processing and modification) 5 Polyphenol – lignin, humic acids 25.10. & 1. 11. Polysaccharides I – starch 8.11. & 15. 11. Polysaccharides II – celullosis 22. & 22. 11. Protein fibres I 29. 11. & 6. 12. Protein fibres II 13. & 20. 12. Casein, whey, protein of eggs 20. 12. Identification of natural polymers Laboratory methods of natural polymers’ evaluation A bit of TERMINOLOGY is NECESSARY •POLYTERPENES •Rubber – Vulcanization – Vulcanized Rubber (Hard Rubber) • •Plant (vegetable) GUMS = POLYSACCHARIDES = Mucilage (GUM) January 2018/4 NATURAL POLYMERS MU SCI 4 2018 3 January 2018/4 NATURAL POLYMERS MU SCI 4 2018 4 Survey of the Plant (vegetable) GUMS Monosaccharide Arabic Gum Traganth Cherry gum Plum gum Peach gum % w/w Glucoronic acid 16 --- 12 15 7 Galactonoric acid --- 43 --- --- --- Arabinose 19 3 55 34 43 Galactose 52 4 21 40 36 Rhamnose 14 --- Traces --- Traces Xylose --- 40 --- 11 14 Manose --- --- 10 --- --- Fucose --- 10 --- --- --- January 2018/4 NATURAL POLYMERS MU SCI 4 2018 5 Alpha-L-Rhamnopyranose.svg Rhamnose Cyklická forma galaktózy Galaktose prevailing form in the water – there can be also one HEXOSA and two PENTOSES January 2018/4 NATURAL POLYMERS MU SCI 4 2018 6 520px-Beta_D-Glucuronic_acid_svg.png Glucoronic acid 800px-Galacturonic_acid.png 157px-Beta-D-Glucopyranose_svg.png b D GLUCOSE Galactose Two different types of saccharides’ formulas Galactonoric acid Plant (vegetable) GUMS and so called „E“ Food Additives •Most of the Plant (vegetable) GUMS belongs to the „E“ Food Additives! •The List of „E“ Food Additives is available on Internet, e.g. https://www.food.gov.uk/science/additives/enumberlist (Open!) •They are used as (act so): –Thickener –Emulsifier –Stabilisers of the Rheological Properties –Bonding agent of the Pills and Tablets in Pharmacy –………….. January 2018/4 NATURAL POLYMERS MU SCI 4 2018 7 Plant (vegetable) GUMS = Mucilage (GUM) 1 January 2018/4 NATURAL POLYMERS MU SCI 4 2018 8 •They are got by collecting of the dry Exudates from the Tree lesions fruit Trees •Their Difference from RESINS is, that they are soluble in Water or at least are strongly swelling •The most common Plant (vegetable) GUMS: •Arabic gum •Tragant •Fruit Trees Gums –Cherry, –Plum, –Peach. Plant (vegetable) GUMS = Mucilage (GUM) 2 January 2018/4 NATURAL POLYMERS MU SCI 4 2018 9 •They are frequently contaminated by Protein substances •The acid part is oxidised saccharides (Glucoronic acid, Galacturic acid), often as salts Ca+2, Mg+2, Na+ •The Acid hydrolysis >possibility of the Decomposition to Saccharides > approved by HPLC analysis •The Solubility DEPENDS also on pH Arabic GUM (E 414) – the most frequent Plant (vegetable) GUMS January 2018/4 NATURAL POLYMERS MU SCI 4 2018 10 File:Gomma arabica.png It looks like the RESIN! Acacia senegal Arabic GUM (E 414) January 2018/4 NATURAL POLYMERS MU SCI 4 2018 11 Gum arabic is a complex mixture of glycoproteins and polysaccharides. It is the original source of the sugars arabinose and ribose, both of which were first discovered and isolated from it, and are named after it. 157px-Beta-D-Arabinopyranose_svg.png arabinose https://upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Alpha-D-Ribofuranose.svg/135px-Alpha-D-Ri bofuranose.svg.png aD Ribose as PENTOSE It exists also b D Ribose and Ribose as HEXOSE https://upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Alpha-D-Ribopyranose.svg/120px-Alpha-D-Ri bopyranose.svg.png Arabic GUM (E 414) •CONTAINS: –Polysaccharides –Glycoproteins- proteins with the bound Saccharides – January 2018/4 NATURAL POLYMERS MU SCI 4 2018 12 Glicoprotein_svg.png Galaotóse – the main Component Arabic GUM (E 414) •The Branched structure •The Molecular weight is approx. 250 000 to 1 000 000 Da •Solubility in Water up to40 % w/w •NONFOOD USE •GLUE (paper, books’ binding) •Colour binding (aquarelle, tempera, pastel) •Tempera •Emulsion water dilutable, e.g. EGG TEMPERA, OIL TEMPERA •Arabic GUM acts here EMULSION STABILISER January 2018/4 NATURAL POLYMERS MU SCI 4 2018 13 Tragacanth E413 January 2018/4 NATURAL POLYMERS MU SCI 4 2018 14 •Plant mucilages having origin from some Asiatic plants sorts of the Plant called Milk-vetch (especially Astragalus gummifer, Astragalus adscendens a Astragalus microcephalus) •It is used as a EMULSION STABILISER, thickening agent for Candy, Sauce a Salad dressing •Colour binding (aquarelle, tempera, pastel) or finishing substance in the textile industry •It is hard to solute in water, it mostly swells only, it does not solute entirely and forms a gel only •It is used for making the pastels • • Fruit Trees gums January 2018/4 NATURAL POLYMERS MU SCI 4 2018 15 •Similar to Arabic gum and Tragacanth –Cherry –Peach –Sour Cherry –Apricot •They mostly swells in Water only (demonstration) •Insoluble in EtOH (demonstration) •The darker Colour > limitation to dark pigments use •Films are relatively (in comparison to Arabic gum) more elastic • • Artifical Mucilage (GUM) January 2018/4 NATURAL POLYMERS MU SCI 4 2018 16 UMĚLÁ KLOVATINA OBRÁZEK.png Glue for paper on the DEXTRINE basis Colour is like the genuine Mucilage Connections are relatively brittle