Testing of IAA (Indol Acid Acetate)
To testing Bacterial that produced IAA production from exopolysaccharide-producing bacteria, NA media and the
addition of L-tryptophan have been used. L-tryptophan is a precursor of IAA will provide a high production rate as
reported [5]. Bacterial isolates were grown on NA medium for 72 hours at 28 0 C in dark conditions. Bacteria that
have grown up after 3 days of incubation were centrifuged at 3000 rpm for 30 minutes. Taken supernatant (2 ml)
was mixed with two drops of orthophosphoric acid and 4 ml of Salcowsci reagent (50 ml, 35% of the sulfuric acid
(H2SO4), 1 ml of 0.5 M solution of FeCl3). To Indicated to IAA production by Pink discoloration showed. Optical