Culture medium optimization for Indole-3-Acetic Acid production by Serratia plymuthica UBCF_13

Abstract

Abstract Serratia plymuthica UBCF_13 is one of the bacteria that can increase plant growth [plant growth-promoting bacteria] by producing IAA [Indole-3-Acetic Acid]. S. plymuthica UBCF_13 is a strain of Andalas University Biotechnology Laboratory Collection which can produce IAA and increase the growth of Solanaceae plants. Optimization of culture media needs to be analyzed to increase IAA production on UBCF_13. Optimization can be done by adding tryptophan as a precursor, using various types of media, adding wall affecting agents, and certain metal ions. In this study, optimization was carried out by testing the type of media [TSB, NB, YM, and King’s B], adding tryptophan [0, 100, 200, 300 μg/mL], differences in pH [5, 6, 7, 8], giving wall affecting agent [SDS 0.1 μg / mL, EDTA 0.1 μg/mL], and metal ions [Ca, Fe, K, Mg at a concentration of 0.05% and 0.1%]. The highest IAA production was obtained in the combination treatment of YM media and tryptophan 300 μg/mL. Meanwhile, the treatment of differences in pH and wall affecting agents did not have a significant effect on the increase in the production of IAA UBCF_13. Testing of metal types on IAA production showed that calcium was able to increase the production of IAA UBCF_13 by 12-14 μg/mL. Serratia plymuthica UBCF_13 produced the highest IAA on YM media combined with the addition of 300 μg/mL of tryptophan and 0.1% calcium ion.