Abstract

Cassava starch is a main renewable bio-resource with low price and mass production in Guangxi, China. It was used as carbon source in growing Xanthomonas campestrispv. campestris 8004 (Xcc 8004) for xanthan gum production in this study. The xanthan gum yield of gelatinized cassava starch was higher than that of raw cassava starch; the maximal reducing sugar and amylase activity reached 14.30 g/L and 1.19U/ml, respectively. The maximal xanthan gum yield of 16.95 g/L was achieved with 30 g/L cassava starch as carbon source. The concentration of residual sugar was 6.82 g/L at the end of fermentation, and the conversion efficiency of sugar reached 73.12%. Thus, Xcc 8004 should be used as a competitive strain for xanthan gum production using cassava starch in industrial applications.

Key words: Xanthan gum, cassava starch, Xanthomonas campestris pv. campestris8004, amylase activity.