Gum tragacanth is one of the most important plant gum which is exudated from the stem of Astragalus gossypinus .Iran is the most important producer of tragacanth. Nowdays in many industries included food, medicine and clinical; gum tragacanth has new and various usages. Chemical structure are mixture of complex polysaccharides with inorganic elements. In this research , samples of gum tragacanth were taken from six sites in west of Isfahan province (Hendokesh and Betlijeh in Fereiden, Ghalejamal in Golpaygan , Rahmatabad in Khansar, Tangebidakan in Mobarakeh and Musaabad in Tirankarvan) and most important carbohydrates, Amino acid and inorganic elements were specified and compared. . Flame photometric and atomic absorption were used to determine the inorganic elements, HPLC for carbohydrates and amino acid analyzer for amino acid determination. The results showed that Arabinose(35/5%) and saccharose(13.6%) have the greatest carbohydrate amount in gum tragacanth. Between 9 amino acids which were recognized and measured, hydroxyproline(173/33 ,nmol/g) was the most, and methoinine the least in amount relatively. The comparison of inorganic elements revealed that calcium and phosphor have the most(0.76 and 0.83% respectively), and nitrogen(0.06%) the least percentage of inorganic elements in gum tragacanth.Ratio of sodium to potassium of gum tragacanth was determined in investigated areas and location NO. 1 had more ration than location No. 6 (3.81 vs. 2.28). Results also showed that increasing ration of sodium to potassium in location No. 1 relates to impact of climatic factors as it increases in cold and wet climates. To investigate relations of quality indexes with some ecologic factors, most important ecologic attributes of investigated areas were determined in three groups: climate (13 factors), soil (16 factors) and physiographic (8 factors). To study existing similarity between investigated areas and dir=ltr Key words: Astragalus gossypinus ,gum tragacanth, amino acid, carbohydrate, inorganic element, Isfahan .
