Page 352 - Pharmacognosy 2 PG303 (1)
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Pharmacognosy-2 (PG303)                              Level 2                Clinical Pharmacy-Pharm D

                  Constituents                •  Mainly Arabin                                          •  Mainly two polysaccharides:-
                                             (Mix. of Ca, Mg and K salts of arabic acid).              Bassorin (a complex of poly methoxylated acids),
                                                                                                       which swell in water but does not dissolve
                                              •  Oxidase enzyme                                         •  Tragacanthin (water soluble)

                        Uses                  •  Demulcent in cough, diarrhea preparations and          •  Suspending agent for insoluble powders,
                                                  lozenges,                                                 Emulsifying agent for oils.
                                              •  suspending &emulsifying agent                          •  Hand lotions, cloth printing.

                    Tests for                Its aqueous solution is, viscous, slightly acidic to
                     Identity                litmus paper.
                                             Aq. Soln. of Gum Arabic +few drops of H2O2 + few           •  Neither blue colored particles
                              •  Oxidase     drops of benzidine T.S.→                                       (Indian Tragacanth)
                              enzyme test    Shake and allow to                        stand→ deep      •  Nor a blue colored soln.
                                             blue or a greenish-                       blue color.          (Gum Arabic)
                                             Aq. Soln. of gum Arabic +1 mL of lead sub-acetate         No flocculent white ppt.
                             •  Lead sub     soln.→ flocculent white
                              acetate test   ppt.
                                             No flocculent white ppt.                                  flocculent white ppt.
                                  •  Lead
                              acetate test
                                             1 g of powdered gum+ 1 mL N/50 iodine                     The particles are colored yellow and
                                             solution→ yellowish brown color.                          may show minute scattered blue points
                            •  Iodine test                                                             due to starch.


















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