Characterization of xanthan gum produced from sugar cane broth

Xanthan gum was produced by Xanthomonas campestris pv. campestris NRRL B-1459 using diluted sugar cane broth in experiments that lasted 24 h. The components used were in g/L: 27.0 sucrose; 2.0 Brewer's yeast; and 0.8 NH4NO3. The mixture was fermented at 750 rpm and 0.35 vvm. These conditions produced xanthan gum with the desired molecular weight and total sugar content, which were 4.2 x 10(6) Da and 85.3%, respectively. The sugar consisted of 43% glucose, 32% mannose and 24% glucuronic acid in a 1.79:1.33:1 ratio. The xanthan gum produced by this method was confirmed by comparing the infrared spectrum of commercial xanthan gum with the infrared spectrum of the xanthan gum produced using this method. The infrared spectra were very similar, which confirmed the identity the xanthan gum produced using our method. The xanthan gum was also evaluated using Proton Nuclear Magnetic Resonance (H-1 NMR). (C) 2011 Elsevier Ltd. All rights reserved.