Use of green coconut shells as an alternative substrate for the production of xanthan gum on different scales of fermentation

Abstract

Xanthan, a biopolymer with extensive industrial applications, is commercially produced by fermenting glucose or sucrose using the bacteria Xanthomonas. Green coconut shells, rich in nutrients, could be an alternative substrate to obtain xanthan. This study aimed to evaluate the production and rheological properties of xanthan obtained on different fermentation scales using green coconut shells as the substrate, using its production from sucrose for comparison. Media containing minimal nutritional requirements (carbon, urea, phosphate) were prepared. Upon changing from the conventional medium to the alternative medium there was a 30% increase in production using the shaker and 81% increase using the bioreactor. Increasing the fermentation scale resulted in an increased yield of xanthan and a 30% increase in apparent viscosity. Coconut shells deserve special attention, constituting a possibility for the large scale production of xanthan with cost reduction and application of a residue.

Keywords

• Xanthan gum
• rheology
• green coconut shells
• Xanthomonas campestris