Xanthan pr
Xanthan
production by a novel mutant strain of Xanthomonas campestris:
Application of statistical design for optimization of process parameters
Mona E.M.Mabrouk1;
Amani, M. D. El-Ahwany2; Maha M. B. Beliah2; Soraya
A. Sabry2
Botany Department, Faculty
of Science, Damanhour University, Egypt1
Botany and Microbiology
Department, Faculty of Science, Alexandria University, Egypt2
Abstract: Xanthan
gum is a microbial polysaccharide of great commercial importance as it
has unusual rheological properties in solution and consequent range
of applications. In this study, a series of mutants were isolated from Xanthomonas
campestris by acridine orange mutagenesis. The gum yield of XC5 mutant
was 15.6 % better than that of the parent strain. Sequential methodology based
on the application of two types of experimental designs was used to optimize
the fermentation conditions for xanthan production from X. campestris strain
XC5 in shaking flask cultures using beet molasses as the sole substrate. Using
Plackett–Burman design, beet molasses and KH2PO4 were
identified as significant variables which highly influenced xanthan gum
production and these variables were subsequently optimized using a steepest
ascent design. The steepest ascent method was demonstrated effectively and
efficiently to approach the neighborhood of the optimum. The optimum medium
composition was found to be: Beet molasses, 100; KH2PO4,
10; MgCl2.6H2O,
0.3; citric acid, 0.5; CaCl2.2H2O, 0.006; NH4Cl, 0.2.
Xanthan production increased markedly from 11.5 to 28g/l, when XC5
strain was cultivated in the optimal medium, compared to the basal.
Mabrouk, M E M ,ElAhwany, A M D , Beliah , MM B,
Sabry, S A. Xanthan production by a novel mutant strain of Xanthomonas
campestris: Application of statistical design for optimization of process
parameters. Life Sci J 2013;10(1):1660-1667] (ISSN:
1097-8135). http://www.lifesciencesite.com.
Keywords: Xanthomonas campestris, mutagenesis, beet molasses; Xanthan; Plackett–Burman design; steepest ascent design.
