Polysaccharides vegetable gums

Polysaccharides such as starch and vegetable gums have important pharmaceutical uses as excipients, binding agents for tablets, emulsifying agents and demulcents. Dextran finds employment as a plasma extender to maintain the osmotic pressure of blood. 

Cellulose not only provides the support substance of wood, but also that for all other plants. Flax stalk husks provide linen and hemp is obtained from the leaves of the sisal plant. Cotton fibers are recovered from the seed hairs of the cotton bush. What are known as vegetable gums, which are also polysaccharides, are to be found in other seeds and algae. Starch is recovered from grain seeds, and starch is a mixture of the polysaccharides amylose and amylopectin. Pectin, an acidic polysaccharide, is provided by fruits. Latices containing the polyprenes natural rubber, balata, gutta percha, or chicle are obtained from certain trees and plants. 

The polysaccharides of most important vegetable gums and mucilages are acidic polysaccharides. According to their primary structure, they maybe divided into ... 

The stabihty of emulsions, as well as of other lyophobic colloids in the presence of emulsifiers, is limited. Therefore emulsion stabihsers are often added. These can be low molecular weight hydrophihc substances (such as glycerol) or hydrophihc coUoids (proteins or polysaccharides, for example, gelatine, pectin, vegetable gums or modified celluloses, respectively), which either increase the viscosity of the emulsions or interact with particles of hydrophobic coUoids and thus allow their association with water. 

Polysaccharides are polymers made up of many monosaccharides joined together by glycoside bonds, and include cellulose, starch, vegetable mucilage and plant gums. 

An attempt has been made to classify gums into two main groups (a) real gums which are those plant products which form a clear solution in water and (b) vegetable mucilages which are those which swell but do not dissolve completely in water. This classification is useful but not entirely satisfactory since there are exceptions. Thus gum traga-canth, a tree exudate and a true plant gum, is only partially soluble in water and exhibits those properties normally attributed to mucilages. In this section of the article the term plant gum will be restricted to those complex acid polysaccharides which are exuded from trees either spontaneously or after mechanical injury. 

Okra Gum Okra gum is a semicrystalline polysaccharide which is obtained from okra vegetables. Okra, which is a tall erect annual plant botanically known as Hibiscus esculentus or Abelmoschus esculentus, is also named as Lady s Finger (Malvaceae). It is grown and consumed for nutrition in Asia and Africa [4,25,70]. 

The components of dietary hber are derived mainly from the cell walls of plant material in the diet. These include cellulose, hemicellulose (P-glucans, arabinoxy-lans, etc.), and pectin, collechvely referred to as the NSP. Food gums, also called hydrocolloids, are polysaccharides and are considered dietary hber. Lignin, a noncarbohydrate component of the cell wall and a nonpolysaccharide, is also included as hber that is very tough. Most edible fruits and vegetables, with the excephon of carrots, contain low levels of lignin. 

---