Production of Indole Acetic Acid by Bacteria Isolated from Ghulkin Glacier

Abstract

The biomes of low temperature areas specifica ll y northern areas of Pakistan have evo lved to be unfriendly for growin g crops, because of their chemica l and physica l arch itectures. To make these areas cu lti vatable many types of biofertilizers are in use now days, but the commercia l biofertilizers avai lab le are less effective in cold climatic conditions. The psychrophili c microbial flora ava il ab le in the Glac iers of northern have significant potential of producing co ld adapted metabolites. Indole acetic ac id produced by mi croorganisms is a good exampl e of biofertilizer produced by natural source, that belong to auxin famil y of pl ant hormone and play significant ro le in growth of plants. The current study aims to screen, optimi ze, produce, purify and characterize co ld adapted bacteria isolated from the Ghulkin Glac ier, Hunza Valley, Gilgit Baltistan, Pakistan. A tota l of29 strai ns were screened fo r the production of Indole Acetic Acid on L-Tryptophan (0.2%) production media. Fermentation conditions for the maximum production of Indole Acetic acid of all se lected iso lates were optimized for which productions were carried out in L-Tryptophan containing broth media using the optim ized conditions. Purifications were done by solvent-so lvent extraction method. Characterization of the se lected strains were carri ed out through Thin layer Chromatography (TLC), Fourier Transform Infrared Spectroscopy (FTIR) and Proton based Nuclear Magnetic Resonance (H-NMR) image was taken. Three stra ins GB29, GB3 and GA9 showed the production of indole acetic acid. Maximum Indo le Acetic Ac id production by GB29 were recorded at 5°C, pH 5, L Tryptophan (0.7%) and Maltose as carbon source after 48 hours of incubation. The optimum conditions for the maximum production of Indo le Acetic Acid by GB3 were recorded at 35°C, pH 7, L Tryptophan (0.9%) and Maltose as carbon so urce after 72 hours of incubation. GA9 carried out maximum production at 5°C, pH 7, L Tryptophan (0.7%) and Maltose as carbon so urce after 72 hours of incubation. The retention factor (Rr) calculated for all the three stra ins were 0.27 which was equal to Rrva lue of standard Indole Acetic Ac id loaded on TLC plate. The similarity of spectra l peaks between standard Indo le Acetic Ac id and extracted Indole Acetic Acid from the selected isolates confirmed the production of hormone. Further confirmation was done by NMR by finding the functional groups present in the indole acetic acid. These cold adapted strai ns isolated from the Ghulkin Glac ier sampl es were good producers of Indo le Acetic Acid which would be used as biofertilizers for crop growth promotion in the cold c limatic regions of Pakistan.