Scale-Up Production of and Identification of Indole Acetic Acid using Waste Glycerol as a Carbon Source in 2-Litre Fermenter

Abstract

The microbial production of Indole- 3-acetic acid (IAA) develops a sustainable and low-cost methods to other traditional methods. This study investigates the scalability of IAA production using four isolated microbial strains Enterobacter asburiae, Bacillus licheniformis, Achromobacter mucicolens, and Pseudomonas fulva in a 2-litre fermenter with an optimized Yeast Extract Glycerol (YEG) medium, where crude glycerol was used as a carbon source. The results of microbial fermentation, with Enterobacter asburiae achieving yields of up to 3477 μg/ml through the indole-3-pyruvate pathway. Critical fermentation parameters such as pH, temperature, and agitation speed were maintained, contributing to consistent IAA production levels. The use of crude glycerol not only enhanced yields but also provided a lowcost substrate, aligning with sustainability goals in agriculture by reducing reliance on synthetic chemicals. Extraction and quantification methods such as High-Performance Liquid Chromatography (HPLC) and Fourier Transform Infrared Spectroscopy (FTIR), DSC and XRD ensured presence of IAA levels in samples. This study highlights the potential for scaling up microbial IAA production through optimized fermentation processes, with significant implications for biotechnological applications in sustainable agriculture and future research directions focusing on further optimization and genetic enhancements.