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43-447: Jeanes is a surname, and may refer to: Allene Jeanes (1906–1995), American chemical researcher Anna T. Jeanes (1822–1907), American philanthropist David Jeanes (born 1943), English former rugby player Susan Jeanes (born 1958), Australian politician Tex Jeanes (1900–1973), American baseball player Steve Jeanes [REDACTED] Surname list This page lists people with

86-573: A master's degree in organic chemistry from the University of California, Berkeley . She was Jewish. From 1930 to 1935, Jeanes was employed as the head science teacher at Athens College in Athens, Alabama . From 1936 to 1937, she held a position as chemistry instructor at the University of Illinois . She received her PhD in organic chemistry from University of Illinois in 1938, after working with Roger Adams . In 1938, Dr. Jeanes decided to accept

129-473: A chemical researcher. She worked there until 1976. Jeanes is credited with "a prominent role in making NRRL a world-class center for applied carbohydrate science". Jeanes' area of research was natural polysaccharides , including starch (found in wheat, corn, rice, and potatoes), cellulose (found in cotton, wood, and paper), and dextran . Jeanes was able to isolate dextran-producing bacteria from samples of bacteria-contaminated root beer supplied by

172-454: A crystalline to amorphous transition when heated beyond 60–70 °C in water (as in cooking), cellulose requires a temperature of 320 °C and pressure of 25 MPa to become amorphous in water. Several types of cellulose are known. These forms are distinguished according to the location of hydrogen bonds between and within strands. Natural cellulose is cellulose I, with structures I α and I β . Cellulose produced by bacteria and algae

215-467: A liquid called bio-oil is obtained at 500 °C. Semi-crystalline cellulose polymers react at pyrolysis temperatures (350–600 °C) in a few seconds; this transformation has been shown to occur via a solid-to-liquid-to-vapor transition, with the liquid (called intermediate liquid cellulose or molten cellulose ) existing for only a fraction of a second. Glycosidic bond cleavage produces short cellulose chains of two-to-seven monomers comprising

258-545: A local Peoria company. This discovery was the basis for development of a mass production process for dextran, and its use in a dextran-based blood plasma extender. This plasma substitute was used by medical personal in the Korean and Vietnam wars. It was believed that using this sort of substance would keep someone who had lost a great deal of blood alive longer. So, the United States began using dextran to treat injured soldiers. As

301-409: A polysaccharide matrix . The high tensile strength of plant stems and of the tree wood also arises from the arrangement of cellulose fibers intimately distributed into the lignin matrix. The mechanical role of cellulose fibers in the wood matrix responsible for its strong structural resistance, can somewhat be compared to that of the reinforcement bars in concrete , lignin playing here the role of

344-722: A position at the National Institutes of Health in Washington D.C. And, from 1938 to 1940, Jeanes served as a corn industries research foundation fellow for the National Institutes of Health (NIH) with Claude Hudson and worked at the National Bureau of Standards with Horace S. Isbell . In 1941 she joined Roy L. Whistler at the U.S. Department of Agriculture ’s Northern Regional Research Lab (NRRL) in Peoria, Illinois , as

387-419: A proper solvent , e.g. in an ionic liquid . Most mammals have limited ability to digest dietary fibre such as cellulose. Some ruminants like cows and sheep contain certain symbiotic anaerobic bacteria (such as Cellulomonas and Ruminococcus spp. ) in the flora of the rumen , and these bacteria produce enzymes called cellulases that hydrolyze cellulose. The breakdown products are then used by

430-716: A result of her work, Jeanes was the first woman to receive the Distinguished Service Award given by the Department of Agriculture, in 1953. She was also awarded the Garvan Medal in 1956. Jeanes was also part of the team that developed xanthan gum . Xanthan gum, derived from Xanthomonas campestris bacteria, completely revolutionized food processing due to its unique thickening and stabilizing properties. It's extensively used in products such as salad dressings, sauces, and baked goods to maintain texture and consistency. In

473-744: A variety of uses. Nitrocellulose was initially used as an explosive and was an early film forming material. When plasticized with camphor , nitrocellulose gives celluloid . Cellulose Ether derivatives include: The sodium carboxymethyl cellulose can be cross-linked to give the croscarmellose sodium (E468) for use as a disintegrant in pharmaceutical formulations. Furthermore, by the covalent attachment of thiol groups to cellulose ethers such as sodium carboxymethyl cellulose, ethyl cellulose or hydroxyethyl cellulose mucoadhesive and permeation enhancing properties can be introduced. Thiolated cellulose derivatives (see thiomers ) exhibit also high binding properties for metal ions. Cellulose for industrial use

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516-685: A wide variety of products. While the first application of regenerated cellulose was as a clothing textile , this class of materials is also used in the production of disposable medical devices as well as fabrication of artificial membranes . The hydroxyl groups (−OH) of cellulose can be partially or fully reacted with various reagents to afford derivatives with useful properties like mainly cellulose esters and cellulose ethers (−OR). In principle, although not always in current industrial practice, cellulosic polymers are renewable resources. Ester derivatives include: Cellulose acetate and cellulose triacetate are film- and fiber-forming materials that find

559-464: Is chiral and is biodegradable . It was shown to melt at 467 °C in pulse tests made by Dauenhauer et al. (2016). It can be broken down chemically into its glucose units by treating it with concentrated mineral acids at high temperature. Cellulose is derived from D -glucose units, which condense through β(1→4)- glycosidic bonds . This linkage motif contrasts with that for α(1→4)-glycosidic bonds present in starch and glycogen . Cellulose

602-698: Is (C 6 H 10 O 5 ) n where n is the degree of polymerization and represents the number of glucose groups. Plant-derived cellulose is usually found in a mixture with hemicellulose , lignin , pectin and other substances, while bacterial cellulose is quite pure, has a much higher water content and higher tensile strength due to higher chain lengths. Cellulose consists of fibrils with crystalline and amorphous regions. These cellulose fibrils may be individualized by mechanical treatment of cellulose pulp, often assisted by chemical oxidation or enzymatic treatment, yielding semi-flexible cellulose nanofibrils generally 200 nm to 1 μm in length depending on

645-551: Is a non-digestible constituent of insoluble dietary fiber , acting as a hydrophilic bulking agent for feces and potentially aiding in defecation . Cellulose was discovered in 1838 by the French chemist Anselme Payen , who isolated it from plant matter and determined its chemical formula. Cellulose was used to produce the first successful thermoplastic polymer , celluloid , by Hyatt Manufacturing Company in 1870. Production of rayon ("artificial silk ") from cellulose began in

688-546: Is a straight chain polymer. Unlike starch, no coiling or branching occurs and the molecule adopts an extended and rather stiff rod-like conformation, aided by the equatorial conformation of the glucose residues. The multiple hydroxyl groups on the glucose from one chain form hydrogen bonds with oxygen atoms on the same or on a neighbour chain, holding the chains firmly together side-by-side and forming microfibrils with high tensile strength . This confers tensile strength in cell walls where cellulose microfibrils are meshed into

731-621: Is different from Wikidata All set index articles Allene Jeanes Jeanes was born July 19, 1906, in Waco, Texas , to Viola (Herring) and Largus Elonzo Jeanes, a switchman and later a yardmaster for the Cotton Belt Route of the St. Louis Southwestern Railway . Allene graduated with honors from Waco High School in 1924. In 1928, she received a bachelor's degree from Baylor University and graduated summa cum laude; in 1929, Jeanes obtained

774-473: Is enriched in I α while cellulose of higher plants consists mainly of I β . Cellulose in regenerated cellulose fibers is cellulose II. The conversion of cellulose I to cellulose II is irreversible, suggesting that cellulose I is metastable and cellulose II is stable. With various chemical treatments it is possible to produce the structures cellulose III and cellulose IV. Many properties of cellulose depend on its chain length or degree of polymerization ,

817-665: Is mainly obtained from wood pulp and from cotton . Energy crops: The major combustible component of non-food energy crops is cellulose, with lignin second. Non-food energy crops produce more usable energy than edible energy crops (which have a large starch component), but still compete with food crops for agricultural land and water resources. Typical non-food energy crops include industrial hemp , switchgrass , Miscanthus , Salix ( willow ), and Populus ( poplar ) species. A strain of Clostridium bacteria found in zebra dung, can convert nearly any form of cellulose into butanol fuel . Another possible application

860-405: Is produced using the same family of proteins, although the gene is called BcsA for "bacterial cellulose synthase" or CelA for "cellulose" in many instances. In fact, plants acquired CesA from the endosymbiosis event that produced the chloroplast . All cellulose synthases known belongs to glucosyltransferase family 2 (GT2). Cellulose synthesis requires chain initiation and elongation, and

903-448: Is short for "cellulose synthase") genes, in an unknown stoichiometry . Separate sets of CesA genes are involved in primary and secondary cell wall biosynthesis. There are known to be about seven subfamilies in the plant CesA superfamily, some of which include the more cryptic, tentatively-named Csl (cellulose synthase-like) enzymes. These cellulose syntheses use UDP-glucose to form the β(1→4)-linked cellulose. Bacterial cellulose

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946-434: Is synthesized at the plasma membrane by rosette terminal complexes (RTCs). The RTCs are hexameric protein structures, approximately 25 nm in diameter, that contain the cellulose synthase enzymes that synthesise the individual cellulose chains. Each RTC floats in the cell's plasma membrane and "spins" a microfibril into the cell wall . RTCs contain at least three different cellulose synthases , encoded by CesA ( Ces

989-426: Is under development as a renewable fuel source. Cellulose for industrial use is mainly obtained from wood pulp and cotton . Cellulose is also greatly affected by direct interaction with several organic liquids. Some animals, particularly ruminants and termites , can digest cellulose with the help of symbiotic micro-organisms that live in their guts, such as Trichonympha . In human nutrition , cellulose

1032-830: Is used in the oil and gas sector for drilling operations, demonstrating the versatility of Jeanes' innovation. The environmental friendliness of xanthan gum, as it is a biodegradable and non-toxic substance, aligns perfectly with current sustainable and environmentally friendly trends, making it a preferred ingredient in various sectors. Overall, Jeanes' work in this development has had a far-reaching impact, contributing significantly to advancements in food science, cosmetics, medicine, and even energy, thereby enhancing various aspects of everyday life. Her innovation and contributions are still in use today in many ways. In her last published paper, "Immunological and Related Interactions with Dextrans Reviewed in Terms of Improved Structural Information," which

1075-495: The glycosidic linkage in cellulose are glycoside hydrolases including endo-acting cellulases and exo-acting glucosidases . Such enzymes are usually secreted as part of multienzyme complexes that may include dockerins and carbohydrate-binding modules . At temperatures above 350 °C, cellulose undergoes thermolysis (also called ' pyrolysis '), decomposing into solid char , vapors, aerosols , and gases such as carbon dioxide . Maximum yield of vapors which condense to

1118-412: The hardened cement paste acting as the "glue" in between the cellulose fibres. Mechanical properties of cellulose in primary plant cell wall are correlated with growth and expansion of plant cells. Live fluorescence microscopy techniques are promising in investigation of the role of cellulose in growing plant cells. Compared to starch, cellulose is also much more crystalline . Whereas starch undergoes

1161-521: The oomycetes . Some species of bacteria secrete it to form biofilms . Cellulose is the most abundant organic polymer on Earth. The cellulose content of cotton fibre is 90%, that of wood is 40–50%, and that of dried hemp is approximately 57%. Cellulose is mainly used to produce paperboard and paper . Smaller quantities are converted into a wide variety of derivative products such as cellophane and rayon . Conversion of cellulose from energy crops into biofuels such as cellulosic ethanol

1204-409: The surname Jeanes . If an internal link intending to refer to a specific person led you to this page, you may wish to change that link by adding the person's given name (s) to the link. Retrieved from " https://en.wikipedia.org/w/index.php?title=Jeanes&oldid=1254724704 " Category : Surnames Hidden categories: Articles with short description Short description

1247-413: The 1890s and cellophane was invented in 1912. Hermann Staudinger determined the polymer structure of cellulose in 1920. The compound was first chemically synthesized (without the use of any biologically derived enzymes ) in 1992, by Kobayashi and Shoda. Cellulose has no taste, is odorless, is hydrophilic with the contact angle of 20–30 degrees, is insoluble in water and most organic solvents ,

1290-525: The Viscose Development Company, is the most widely used method for manufacturing regenerated cellulose products. Courtaulds purchased the patents for this process in 1904, leading to significant growth of viscose fiber production. By 1931, expiration of patents for the viscose process led to its adoption worldwide. Global production of regenerated cellulose fiber peaked in 1973 at 3,856,000 tons. Regenerated cellulose can be used to manufacture

1333-410: The bacteria for proliferation. The bacterial mass is later digested by the ruminant in its digestive system ( stomach and small intestine ). Horses use cellulose in their diet by fermentation in their hindgut . Some termites contain in their hindguts certain flagellate protozoa producing such enzymes, whereas others contain bacteria or may produce cellulase. The enzymes used to cleave

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1376-446: The basis of commercial technologies. These dissolution processes are reversible and are used in the production of regenerated celluloses (such as viscose and cellophane ) from dissolving pulp . The most important solubilizing agent is carbon disulfide in the presence of alkali. Other agents include Schweizer's reagent , N -methylmorpholine N -oxide , and lithium chloride in dimethylacetamide . In general, these agents modify

1419-450: The biomass of land plants . In contrast to cellulose, hemicelluloses are derived from several sugars in addition to glucose , especially xylose but also including mannose , galactose , rhamnose , and arabinose . Hemicelluloses consist of shorter chains – between 500 and 3000 sugar units. Furthermore, hemicelluloses are branched, whereas cellulose is unbranched. Cellulose is soluble in several kinds of media, several of which are

1462-446: The cellulose was historically termed "tunicine" (tunicin)). Cellulolysis is the process of breaking down cellulose into smaller polysaccharides called cellodextrins or completely into glucose units; this is a hydrolysis reaction. Because cellulose molecules bind strongly to each other, cellulolysis is relatively difficult compared to the breakdown of other polysaccharides . However, this process can be significantly intensified in

1505-557: The cellulose, rendering it soluble. The agents are then removed concomitant with the formation of fibers. Cellulose is also soluble in many kinds of ionic liquids . The history of regenerated cellulose is often cited as beginning with George Audemars, who first manufactured regenerated nitrocellulose fibers in 1855. Although these fibers were soft and strong -resembling silk- they had the drawback of being highly flammable. Hilaire de Chardonnet perfected production of nitrocellulose fibers, but manufacturing of these fibers by his process

1548-479: The cosmetics industry, xanthan gum improves the texture of creams and lotions, making them more appealing to consumers. In medicine, xanthan gum plays a role in creating more appetizing and stable pharmaceutical products. It's also essential in gluten-free baking, providing a substitute that mimics the texture and properties of gluten, greatly benefiting those with gluten intolerances or celiac disease. Moreover, xanthan gum has applications beyond these industries. It

1591-602: The melt. Vapor bubbling of intermediate liquid cellulose produces aerosols , which consist of short chain anhydro-oligomers derived from the melt. Continuing decomposition of molten cellulose produces volatile compounds including levoglucosan , furans , pyrans , light oxygenates, and gases via primary reactions. Within thick cellulose samples, volatile compounds such as levoglucosan undergo 'secondary reactions' to volatile products including pyrans and light oxygenates such as glycolaldehyde . Hemicelluloses are polysaccharides related to cellulose that comprises about 20% of

1634-508: The number of glucose units that make up one polymer molecule. Cellulose from wood pulp has typical chain lengths between 300 and 1700 units; cotton and other plant fibers as well as bacterial cellulose have chain lengths ranging from 800 to 10,000 units. Molecules with very small chain length resulting from the breakdown of cellulose are known as cellodextrins ; in contrast to long-chain cellulose, cellodextrins are typically soluble in water and organic solvents. The chemical formula of cellulose

1677-524: The treatment intensity. Cellulose pulp may also be treated with strong acid to hydrolyze the amorphous fibril regions, thereby producing short rigid cellulose nanocrystals a few 100 nm in length. These nanocelluloses are of high technological interest due to their self-assembly into cholesteric liquid crystals , production of hydrogels or aerogels , use in nanocomposites with superior thermal and mechanical properties, and use as Pickering stabilizers for emulsions . In plants cellulose

1720-430: The two processes are separate. Cellulose synthase ( CesA ) initiates cellulose polymerization using a steroid primer, sitosterol -beta- glucoside , and UDP-glucose. It then utilises UDP -D-glucose precursors to elongate the growing cellulose chain. A cellulase may function to cleave the primer from the mature chain. Cellulose is also synthesised by tunicate animals, particularly in the tests of ascidians (where

1763-400: Was 89 years old. Cellulose Cellulose is an organic compound with the formula ( C 6 H 10 O 5 ) n , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D -glucose units. Cellulose is an important structural component of the primary cell wall of green plants , many forms of algae and

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1806-549: Was published in 1986, Jeanes shows her dedication to her work. Over the course of her entire career, Allene Jeanes was awarded ten patents and produced sixty publications. These were all related to her work and discoveries. She was ultimately honored with a plethora of awards. She was a member of the American Chemical Society , Sigma Xi , and Iota Sigma Pi . Jeanes died on December 11, 1995 in Urbana , Illinois. She

1849-409: Was relatively uneconomical. In 1890, L.H. Despeissis invented the cuprammonium process – which uses a cuprammonium solution to solubilize cellulose – a method still used today for production of artificial silk . In 1891, it was discovered that treatment of cellulose with alkali and carbon disulfide generated a soluble cellulose derivative known as viscose . This process, patented by the founders of

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