starch


starch
A high molecular weight polysaccharide built up of d-glucose residues in α-1,4 linkage, differing from cellulose in the presence of α- rather than β-glucoside linkages, that exists in most plant tissues; converted into dextrin when subjected to the action of dry heat, and into dextrin and d-glucose by amylases and glucoamylases in saliva and pancreatic juice; used as a dusting powder, an emollient, and an ingredient in medicinal tablets, and is an important raw material for the manufacture of alcohol, acetone, n-butanol, lactic acid, citric acid, glycerine, and gluconic acid by fermentation; chief storage carbohydrate in most higher plants. SYN: amylum. [A.S. stearc, strong]
- animal s. SYN: glycogen.
- liver s. SYN: glycogen.
- moss s. SYN: lichenin.
- rice s. rice product used as a supplement in many media formulations used for the culture of intestinal protozoa ( e.g., Entamoeba histolytica).
- soluble s. a high molecular weight, water-soluble dextrin produced by the partial acid hydrolysis of s.; useful in iodimetry, as it gives an easily visible purple-black end point in the presence of free iodine.

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starch 'stärch n a white odorless tasteless granular or powdery complex carbohydrate (C6H10O5)x that is the chief storage form of carbohydrate in plants, is an important foodstuff, has demulcent and absorbent properties, and is used in pharmacy esp. as a dusting powder and as a constituent of ointments and pastes

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n.
the form in which carbohydrate are stored in many plants and a major constituent of the diet. Starch consists of linked glucose units and occurs in two forms, a-amylose and amylopectin. In a-amylose the units are in the form of a long unbranched chain; in amylopectin they form a branched chain. The presence of starch can be detected using iodine: a-amylose gives a blue colour with iodine; amylopectin a red colour. Starch is digested by means of the enzyme amylase. See also dextrin.

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(stahrch) [A.S. stercan to stiffen] any of a group of polysaccharides of the general formula (C6H10O5)n, composed of a long-chain polymer of glucose in the form of amylose and amylopectin; it is the chief storage form of energy reserve (carbohydrates) in plants. [NF] a preparation consisting of the granules separated from the mature grain of corn or wheat, or from potato tubers, occurring as irregular, angular, white masses or fine powder; used as a dusting powder and as a filler, binder, and disintegrant in pharmaceutical preparations.

Medical dictionary. 2011.

Look at other dictionaries:

  • Starch — Starch, CAS# 9005 25 8, chemical formula (C6H10O5)n is a polysaccharide carbohydrate consisting of a large number of glucose monosaccharide units joined together by glycosidic bonds. All plant seeds and tubers contain starch which is… …   Wikipedia

  • starch´i|ly — starch|y «STAHR chee», adjective, starch|i|er, starch|i|est. 1. like starch. 2. composed of starch. 3. containing starch …   Useful english dictionary

  • starch|y — «STAHR chee», adjective, starch|i|er, starch|i|est. 1. like starch. 2. composed of starch. 3. containing starch …   Useful english dictionary

  • Starch — Starch, n. [From starch stiff, cf. G. st[ a]rke, fr. stark strong.] 1. (Chem.) A widely diffused vegetable substance found especially in seeds, bulbs, and tubers, and extracted (as from potatoes, corn, rice, etc.) as a white, glistening, granular …   The Collaborative International Dictionary of English

  • Starch — Starch, v. t. [imp. & p. p. {Starched} (st[aum]rcht); p. pr. & vb. n. {Starching}.] To stiffen with starch. [1913 Webster] …   The Collaborative International Dictionary of English

  • starch — [stärch] n. [ME starche < sterchen, to stiffen < OE * stercan < stearc, rigid, stiff, akin to Ger stark, strong: see STARK] 1. a white, tasteless, odorless food substance found in potatoes, rice, corn, wheat, cassava, and many other… …   English World dictionary

  • Starch — (st[aum]rch), a. [AS. stearc stark, strong, rough. See {Stark}.] Stiff; precise; rigid. [R.] Killingbeck. [1913 Webster] …   The Collaborative International Dictionary of English

  • starch — (v.) c.1400, from O.E. *stercan (Mercian), *stiercan (W.Saxon) make rigid, found in stercedferhð fixed, hard, resolute (related to stearc stiff ), from P.Gmc. *starkijanan (Cf. Ger. Stärke strength, starch ), from PIE root *ster strong, firm,… …   Etymology dictionary

  • starch — ► NOUN 1) an odourless, tasteless carbohydrate which is obtained chiefly from cereals and potatoes and is an important constituent of the human diet. 2) powder or spray made from this substance, used to stiffen fabric. 3) stiffness of manner. ►… …   English terms dictionary

  • starch — starch. См. крахмал. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • starch — [ startʃ ] noun 1. ) uncount a substance used for making clothes stiff 2. ) count or uncount a white substance without any taste that is found in rice, potatoes, and other vegetables. It is a type of CARBOHYDRATE that gives you energy …   Usage of the words and phrases in modern English