1. Broad generic term for what are now called pectic substances or materials; specifically, a gelatinous substance, consisting largely of long chains of mostly d-galacturonic acid units (typically α-1,4 linkages and sometimes present as methyl esters), that is extracted from fruits where it is presumed to exist as protopectin (pectose). 2. Commercial pectins, sometimes called pectinic acid, are whitish, soluble powders prepared from the rinds of citrus fruits. They are used in the preparation of jams, jellies, and similar food products where they enhance viscosity; therapeutically, they are used to control diarrhea (usually in conjunction with other agents), as a plasma expander, and as a protectant; pectins bind calcium ions and are highly hydrated.
- p. lyase an enzyme that catalyzes the elimination of 6-methyl-Δ-4,5-d-galacturonate residues from p.; thus, it brings about depolymerization; it does not act on deesterified p.; used in the treatment of certain foodstuffs.
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pec·tin 'pek-tən n
1) any of various water-soluble substances that bind adjacent cell walls in plant tissues and yield a gel which is the basis of fruit jellies
2) a commercial product rich in pectins and used chiefly in making jelly and other foods, in pharmaceutical products esp. for the control of diarrhea, and in cosmetics
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pec·tin (pekґtin) [Gr. pēktos congealed] 1. a polymer of sugar acids of fruit that forms gels with sugar at the proper pH. 2. [USP] a purified preparation obtained from the acid extract of the inner portion of the rind of citrus fruits or from apple pomace, consisting chiefly of partially methoxylated polygalacturonic acids; used in the treatment of diarrhea, and as a thickening and emulsifying agent in pharmaceutical preparations.Medical dictionary. 2011.