Cellulose is an abundant polysaccharide consisting of a β-1, 4 linkage of D-glucose [1,3]. There is an array of applications for cellulose, including, but not limited to: biofuels, reinforcement agents, thickeners, dietary fiber, and even wound care. As of late, cellulose, as a waste product, has been in high demand as a reinforcement agent in synthetic, petroleum-based polymer matrices (petroleum based plastics) [3]. Cellulose I has good flexibility, it is abundant in nature and also biodegradable. Because of its fiber- like structure, it has been compared to carbon nanotubes (CNT’s) [3]. Working with cellulose poses some problems, as it is inherently difficult to manipulate due to its chemical structure [1,3]. Cellulose is naturally …show more content…
Purity is defined as the ratio between the amount of crystalline regions and the amorphous regions present in cellulose [2,5,7,8]. Essentially, the more crystalline regions you have, the purer the cellulose, the more thermally stable and mechanically strongr the cellulose. This can be achieved by extracting the amorphous cellulose from the cellulose matrix [3,5,7]. Cellulose is also produced by bacteria, as well as animals, called bacterial cellulose (BC), and tunicin cellulose, respectively [3]. Bacterial cellulose has shown to have better thermal, and mechanical properties than the plant derived cellulose [3]. Specific bacteria called Symbiotic Culture Of Bacteria and Yeast (SCOBY) produce bacterial cellulose. These bacteria create the cellulose to form small pockets in which they live, using it as a protective shell or coating from the outside environment. Tunicin cellulose comes from the mantle of tunicate, a sea-shelled animal that produces cellulose identical to one of which is found in plants [3 …show more content…
Nano materials have gained great attention with their high surface area and great reactivity. Nano scale synthesis is achieved by two ways: a top down approach (take a larger particles and scale them down), a bottom up (normally chemical synthesis). Because of the abundance of cellulose, a top down approach was selected, although; bottom-up approaches yield a more desirable product with the least amount of defects. The microcrystalline cellulose (Iα, Iβ) is then digested with sulfuric acid this specifically targets the amorphous regions breaking the polymer chain into oligomers on to the nano scale [5,8]. Depending on the concentration of acid will either yield cellulose nano fibrils (CNF’s) or, cellulose nano crystals (CNC’s). CNF’s though still on the micro scale in length are defined as their size in diameter of which ranges from 4-7nm in width [8,14]. Lyophilization aides in the self-assembly behavior as the cellulose begins to align chirally. There are four chiral carbons on each monomer unit of the nanocellulose (2,3,4,5) [1718], which align with chiral carbons from adjacent nanocellulose polymers. Due to the chiral, pneumatic alignment of the nanocellulose during sublimation, a uniform dispersion of cellulose is obtained throughout the polymer composites
steps to obtain pure xylose. Moreover, the yield of xylitol is only 50 % of
Cytosolic β-Glucosidase (hCBG) is a xenobiotic-metabolizing enzyme that hydrolyses certain flavonoid glucosides. This type of enzymes play a role in the metabolic detoxification, with a series of enzymatic reactions that neutralize and solubilize toxins, and then transport them to secretory organs. Flavonoid glusocides is a family of molecules in which a sugar is bound to another functional group by a glycosidic bond, and play numerous roles in living organisms, mainly in plants.
How the polymer chains are put together is important, as it improves the properties of the material. The flexibility, strength and stiffness of Kevlar fiber, is dependent on the orientation of the polymer chains. Kevlar fiber is an arrangement of molecules, oriented parallel to each other. This orderly, untangled arrangement of molecules is described as a “Crystalline Structure”. A manufacturing process known as ‘Spinning’ is needed to achieve this crystallinity structure.
In conclusion, essentially cotton got the United States of America up and running, with some help of course. There were many things that pushed the cotton industry along including the British textile industry, to the Cotton Gin, to the steam boat being able to transport more cotton. Cotton, or “white gold” was a key factor in American history, claiming the south as “The Cotton Kingdom.”
Cushman, Lynd, Nichols, Wyman. “Fuel Ethanol from Cellulosic Biomass.” Science. March 1991. Vol 251 (4999):1321
We have discussed various cell-wall associated biopolymers. Select one irregular biopolymer and describe its structural arrangements in the context of molecular and supramolecular level -- draw sketches. Indicate an experimental technique that could show how the biopolymer may respond to abiotic/environmental stresses
It is synthesised in plants, algae and even in some animals, and it can also be synthesised by some bacteria. Cellulose, the major chemical component of fiber wall. Cellulose has a strong tendency to form intra- and inter-molecular hydrogen bonds by the hydroxyl groups on these linear cellulose chains, which stiffen the straight chain and promote aggregation into a crystalline structure and give cellulose a multitude of partially crystalline fiber structures and morphologies. Hemicelluloses are a group of heterogeneous polymers that play a supporting role in the
...ulose will be protected from anything that could potentially damage the cell otherwise. It also plays a part in helping cells keep their shape. Cell walls, along with cellulose, provide support for plants so that they can grow tall while maintaining their shape. The size of the plant will determine the amount of cellulose it will need, but all plants require some amount of it and make use of it constantly.
Enzymes, such as cellulases, which catalyse the breakdown of cellulose, have been isolated from several different organisms, including fungi. However, the purification of enzyme from these sources is expensive, on the order of $5.50 per gallon of ethanol produced. Genetic engineering or biotechnology has already played a key enabling role in the development of cellulosic biomass conversion technologies by dramatically reducing the cost of cellulase production from about $5.50 per gallon of ethanol to $0.10-15 per gallon of
From my reading I learned that cellular respiration is a multi-step metabolic reaction type process that takes place in each living organism 's cell rather it be plant or animal. It’s my understanding that there are two types of cellular respiration, one called aerobic cellular respiration which required oxygen and anaerobic cellular respiration that does not require oxygen. In the anaerobic cellular respiration process, unlike the aerobic process oxygen is not required nor is it the last electron acceptor there by producing fewer ATP molecules and releasing byproducts of alcohol or lactic acid. The anaerobic cellular respiration process starts out exactly the same as anaerobic respiration, but stops part way through due to oxygen not being
The preparation of making wood into a pulp for papermaking is accomplished in two different ways. In the groundwood process, blocks of wood are held against a fast revolving grindstone that shreds off short wood fibbers from the block. The fibbers produced by this process are short and are used only in the production of cheap newsprint and used to be added with other types of wood fibber in the making of high-quality paper. Another technique uses a chemical-solvent processes where wood chips are treated with solvents that remove “resinous material and lignin” from the wood, leaving pure fibbers of cellulose.
present at all times but it must retain some of them. All plant life on Earth benefits from the ability of water to make a hydrogen bond with another substance of similar electronegative charge. Cellulose, the substance that makes up cell walls and paper products, is a hydrophilic substance ("water-loving"). It interacts with water but, unlike other hydrophilic substances, it will not dissolve in it. Cellulose can form strong hydrogen bonds with water molecules. This explains why a paper towel will "wick" water upwards when it comes in contact with it.
Fabrics can be made of natural and synthetic materials. Natural fabrics, like cotton (NY Fashion Center) for example, are found here on earth while synthetic fabrics are manmade (MV Styles). There are many distinguish ways to determine if a fabric is natural or synthetic. Each fabric is different in its own way due to it reaction to heat, its odor, residue and chemicals (MV Styles). Fabrics are seen and used every day and in every way. Synthetic material has been pushed more into the picture because it much easier to make and the cheapest to buy. Synthetic materials are sometimes made form fossil fuels like coal. Cotton and Broadcloth are natural fabrics; Polyester is synthetic and Flannel in a synthetic blend with cotton. Fabrics are made up of fibers which have their own chemical structure, which determines their classification. Polymers make up the fibers (Ball-Deslich and Funkhouser). Since cotton is natural, it comes from a natural cellulose fiber with the polymer of glucose (Cotton). Polyester is synthetic which can be classified as saturated or u...
The following dissertation will discuss on the fabrication of electrospun PCL nanofibre for tissue regeneration. This is to address the limitation faced by current TE scaffold. As there are insufficient focus on the production of PCL nanofibres with surface morphology and even fibre diameters for the use for tissue regeneration. On top of that, biopolymer such as PCL has the ability to degrade over time and still produce the porous structure desired by the nanofibre.[17] Hence, to control the fabrication of PCL nanofibre, the effects of the electrospun parameters is studied in the following dissertation. On top of that, the dissertation will investigate the fabrication of electrospun PCL nanofibre scaffolds for tissue regeneration.
Because cells are the ‘basic unit of life’, the study of cells, cytology, can be considered one of the most important areas of biological research. Almost every day on the evening news, we are told about new discoveries in cell biology, such as cancer research, cloning, and embryology. (https://highered.mheducation.com/sites/0073031216/student_view0/exercise3/the_importance_of_cell_biology.html)