CHEMICAL COMPOSITION OF GROWTH MEDIUM FOR XANTHAN GUM PRODUCTION BY XANTHOMONAS CAMPESTRIS BACTERIA

IINGIT

Abstract

This research aimed to investigate the impact of variable components of the growth medium on the yield of xanthan gum produced by Xanthomonas campestris bacteria. Specifically, different carbon and nitrogen sources were compared to determine the most effective combination for enhancing xanthan gum production. Fermentation experiments were carried out in Erlenmeyer flasks over a period of 120 hours with continuous aeration in a shaking incubator (Inforce Multitron HT). Xanthan gum was then extracted from the fermentation broth using alcohol precipitation, and the yields were evaluated. Further analysis was conducted using IR spectroscopy (FTIR Shimadzu IRTracer 100) and viscosimetry (Brookfield LVDV-II+ Pro) to compare the synthesized sample with a commercial sample of xanthan gum. During the investigation, optimal sources of carbon and nitrogen for biosynthesis were determined (molasses at a concentration of 20 g/l and yeast extract at a concentration of 1 g/l). The yield of the target product under these conditions was 7.62 g/l (38.1% of the total carbon source concentration of 20 g/l) and 14.41 g/l (28.82% of the total carbon source concentration of 50 g/l) respectively. When xanthan gum was cultured in a nutrient medium containing both components, the yield was 10.6 g/l (53% of the total carbon source concentration of 20 g/l). Analysis with IR spectroscopy and viscometry indicated a high similarity between the produced xanthan gum and commercial xanthan gum. These findings demonstrate the potential for utilizing an alternative growth medium composition to enhance exopolysaccharide biosynthesis by Xanthomonas campestris B-6720 bacteria, as well as the ability to use secondary raw materials in xanthan gum production.