Sustainable Carbon Source Utilization for Indole-3-Acetic Acid Production by Marine Pseudomonas fluorescens BCPBMS-1 Using the One-Factor-at-a-Time Approach

Background and Objective: Indole-3 acetic acid (IAA) is a phytohormone that stimulates plant growth and facilitates plant development. Indole-3-acetic acid is a widely occurring endogenous plant hormone that has been shown to enhance root development and morphology. The current study involved the extraction of IAA from marine Pseudomonas fluorescensBCPBMS-1. Materials and Methods: Indole acetic acid (IAA) production in P. fluorescens was screened using Luria broth with L-tryptophan and detected calorimetrically with the Salkowski reagent. Optimization involved testing various factors, including temperature, pH, salinity, incubation time and different carbon and nitrogen sources. The IAA concentration was measured spectrophotometrically at 530 nm using a standard IAA curve. Results: The optimized conditions for maximum IAA production are 30°C, pH 6, 10 ppt salinity and 72 hrs of incubation. Glucose and yeast extract were the most effective carbon and nitrogen sources, respectively, while soybean husk was the best low-cost alternative. Mass-scale synthesis under these conditions yielded 0.72 μg/mL IAA using cost-effective substrates and precise parameters. Conclusion: Microbes’ ability to produce indole-3-acetic acid (IAA) offers an economical replacement for expensive and unreliable chemical IAA synthesis methods. According to this study, soybean husk represents a more economical carbon source for the production of IAA.