Search results
Results From The WOW.Com Content Network
Rice starch as surface treatment of paper has been used in paper production in China since 700 CE. [10] In the mid eighth century production of paper that was sized with wheat starch started in the Arabic world. [11] Laundry starch was first described in England in the beginning of the 15th century and was essential to make 16th century ruffed ...
Starch, cellulose, and glycogen ("animal starch") are common glucose polymers (polysaccharides). Some of these polymers (starch or glycogen) serve as energy stores, while others (cellulose and chitin, which is made from a derivative of glucose) have structural roles. Oligosaccharides of glucose combined with other sugars serve as important ...
The 2-ketohexoses psicose, fructose and tagatose occur naturally as the D-isomers, whereas sorbose occurs naturally as the L-isomer. D-Sorbose is commonly used in the commercial synthesis of ascorbic acid. [10] D-Tagatose is a rare natural ketohexose that is found in small quantities in food. [11]
Glucose, used as an energy source and for the synthesis of starch, glycogen and cellulose, is a hexose. Ribose and deoxyribose (in RNA and DNA , respectively) are pentose sugars. Examples of heptoses include the ketoses mannoheptulose and sedoheptulose .
Cellulose is a polymer made with repeated glucose units bonded together by beta-linkages. Humans and many animals lack an enzyme to break the beta-linkages, so they do not digest cellulose. Certain animals, such as termites can digest cellulose, because bacteria possessing the enzyme are present in their gut. Cellulose is insoluble in water.
Cellulose is the most abundant organic polymer on Earth. [6] The cellulose content of cotton fibre is 90%, that of wood is 40–50%, and that of dried hemp is approximately 57%. [7] [8] [9] Cellulose is mainly used to produce paperboard and paper. Smaller quantities are converted into a wide variety of derivative products such as cellophane and ...
Starch: Starch is an inexpensive biodegradable biopolymer and copious in supply. Nanofibers and microfibers can be added to the polymer matrix to increase the mechanical properties of starch improving elasticity and strength. Without the fibers, starch has poor mechanical properties due to its sensitivity to moisture.
In the isomer isomaltose, the two glucose molecules are joined with an α(1→6) bond. Maltose is the two-unit member of the amylose homologous series , the key structural motif of starch . When beta-amylase breaks down starch, it removes two glucose units at a time, producing maltose.