Annual plants starch

Animal biomass. Vegetal biomass. Wood, Cellulose, Lignins, Hemicelluloses, Natural rubber, Suberin, Tannins, Rosins, Terpenes, Annual plants. Starch, Vegetable oils, Hemicelluloses, Mono and disaccharides, Polylactic acid. Algae, Chitin, Chitosan, Proteins, Cellulose whiskers. Bacterial polymers. Poly (hydro xyalkanoates). Bacterial cellulose... 

This chapter gives a general introduction to the book and describes briefly the context for which the editors established its contents and explains why certain topics were excluded from it. It covers the main raw materials based on vegetable resources, namely (i) wood and its main components cellulose, lignin, hemicelluloses, tannins, rosins and terpenes, as well as species-speciflc constituents, like natural rubber and suberin and (ii) annual plants as sources of starch, vegetable oils, hemicelluloses, mono and disaccharides and algae. Then, the main animal biomass constituents are briefly described, with particular emphasis on chitin, chitosan, proteins and cellulose whiskers from molluscs. Finally, bacterial polymers such as poly(hydroxyalkanoates) and bacterial cellulose are evoked. For each relevant renewable source, this survey alerts the reader to the corresponding chapter in the book. 

The relevant contribution of the output of annual plants to the realm of polymer synthesis and applications stems, instead, from some specific products, namely starch as a polymer, vegetable oils as triglyceride oligomers and hemicelluloses and monosaccharides as potential monomers or precursors to furan derivatives. 

Polylactic acid or PLA is a plastic made from com, an annually renewable resource, leading to 100% biodegradability and compostability. Plastic products made from com are in all common household products all around the world. The NatureWorks PLA is derived from naturally occurring plant starch. According to the NatureWorks LLC website, the different steps of the transformation of plant sugar into NatureWorks PLA are the following [14] ... 

Use of renewable feedstocks is most likely where they can compete economically with petrochemically derived materials. This already happens in many areas, and it is sometimes forgotten that even in a world that seems to be dominated by chemicals and materials from fossil carbon and other non-renewable sources, industry already uses annually 19.8 MT of vegetable oils, 22.5 MT starch, 28.4 MT of plant fibres and 42.5 MT of wood pulp. These all compete on price and performance with synthetic alternatives. 

Xylan occurs in practically all land plants and is said to be present in some marine algae.6 In both wide botanical distribution and abundance in nature it closely follows cellulose and starch. It is most abundant in annual crops, particularly in agricultural residues such as corn cobs, corn stalks, grain hulls and stems. Here it occurs in amounts ranging from 15 to 30%. Hard woods contain 20 to 25% xylan while soft woods contain 7 to 12 %. Spring wood has more pentosan than summer wood. 7 Low strength vegetable fibers of commerce such as jute, sisal, Manila... 

Starch is one of the most abimdant plant polysaccharides and is a major source of carbohydrates and energy in the human diet (Zobel and Stephen, 1995). Starch is the most widely used hydrocolloid in the food industry (Wanous, 2004), and is also a widely used industrial substrate polymer. Total annual world production of starch is approximately 60 million MT and it is predicted to increase by additional approximately 10 million MT by 2010 (FAO, 2006b LMC International, 2002 S. K. Patil and Associates, 2007). Com/maize Zea mays L.), cassava (also known as tapioca—Manihot escu-lenta Crantn.), sweet potato Ipomoea batatas L.), wheat Triticum aestivum L.), and potato Solanum tuberosum L.) are the major sources of starch, while rice Oryza sativa L.), barley Hordeum vulgare L.), sago Cycas spp.), arrowroot Tacca leontopetaloides (L.) Kimtze), buckwheat Fagopyrum esculentum Moench), etc. contribute in lesser amounts to total global production. 

Estimated annual world wheat starch production was 2.11 million tons in 1993 and increased to 2.36 million tons in 1996.28 Because of significant expansion in manufacturing capacity in several countries, wheat starch production rose to 4.67 million tons in 2007 (Table 10.2).42 However, this production figure for wheat starch represents only a small fraction of the total world starch production of 60 million tons 41 By raw materials, wheat represents only 8% of world starch production, while potato, cassava and other crops contribute 4%, 14% and 1%, respectively com dominates at 73%. Approximately 52% of world starch is produced in the USA, 17% in the EU and 31% in other places 43 Wheat starch (<0.5% protein) is commercially produced in about 59 manufacturing plants in some 30 countries. The top 10 producers are France, the United States, Germany, The Netherlands, Australia, the United Kingdom, Belgium, Canada, Japan and China. 

Starch offers several potential advantages as a raw material for plastics applications. It is annually renewable, obtained from a variety of plant sources and is a low-cost material. Interest in its use in biodegradable plastics is also driven by the inherent biodegradability of starch and the ubiquity of microorganisms capable of utilizing starch as a carbon source. 

D-Glucose is the most common of the monosaccharides, occurring in the free state in the blood of animals and in the polymerized state, inter alia, as starch and cellulose. Tens of millions of tons of these polysaccharides are made by plants and photosynthetic microbes annually. A detailed study of the structure of glucose is justified on these grounds, and many of the structural features of all monosaccharides can be illustrated using glucose as an example. 

Adapted from Paszner and Cho (1989). The yield figures are either in annual units per hectare of growth area or in units per tonne of plant part. Includes starch. 

Furda, I. Gengler, S.C. Johnson, R.R. Magnuson, J.S. Smith, D.E. Complete carbohydrate analysis - sugar, starch, and total dietary fat in plant residue and food products. Proc. 93rd annual Association of Official Analytical Chemists. Washington, D.C., 1979. 

Biomass production on Earth corresponds to around 120,000 Mt per year. However, only 5% of that biomass is captured and used by hirmans, and of those 6,000 Mt, only 5% is not destined for energy or food usage. Thus, 300 Mt are already used for chemistry. Yet these quantities are fairly close to the 500 Mt of fossil resomces used annually for chemistry, so we can see the significant potential for substitution of fossil resources by increasing use of renewable resources. The resomces ttsed essential are starch and its derivatives - sugar, ethanol, etc. - cellulose, vegetable oil and glycerol, plant fibers, etc. 

Maize (Zea mays) is part of the cereals, a group of grasses taxonomically belonging to the Poaceae family. It is an annual crop that can reach a height of 4 m. Corncobs represent the female inflorescences and develop 8-18 rows of 25-50 kernels. The C4 plant has a starch content of about 62% (fresh matter) [15]. 

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