Exudate Tree Gums: Properties and Applications

Abstract

The exudate gums are complex polysaccharide substances produced by various trees and, as a part of their natural defense system. In India, the exudate gums are classified under non-timber forest produce, gathered from forests by tribals and marketed by Government organizations. They are structurally characterized under arabinogalactan, glucuronoarabinogalactan, rhamnogalacturonan, rhamnogalacturonoglycan and glucuronoarabinogalactan. The important exudate gums are arabic, karaya, kondagogu, ghatti, tragacanth and olibanum. The exudate gums are extensively used by mankind in different fields and industries such in food, pharmaceutical, textile, paper, paint, pigment, print, ceramic, cosmetic, nano-biotechnology and non-food applications owing to their renewability, low price, nontoxicity, biocompatibility and biodegradability. They are used as stabilizer, thickener, emulsifier in dairy, bakery products; beverages, confectionary, etc. In pharmaceutical industry, they are utilized as adhesive, emollient, demulcent, binder, excipient, tablet disintegrant, drug carrier, etc. They are also employed towards green synthesis of metal and metal oxide nanoparticles. The nanoparticles are exploited as bactericide, fungicide, antibiofilm and cytotoxic agent; drug carrier, colorimetric sensor, antioxidant, catalyst, adsorbent, etc. Further studies are needed on breeding, propagation and tapping methods; yield assessment, trade evaluation and application widening of exudate gums.