Table of Contents
Journal of Polymers
Volume 2013 (2013), Article ID 692374, 7 pages
http://dx.doi.org/10.1155/2013/692374
Research Article

Optimization of Cultural Conditions for Production of Extracellular Polymeric Substances (EPS) by Serpentine Rhizobacterium Cupriavidus pauculus KPS 201

1Department of Botany, Serampore College, 9 William Carey Road, Serampore, Hooghly, West Bengal 712 201, India
2Microbiology Laboratory, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700 019, India

Received 30 March 2013; Revised 10 October 2013; Accepted 11 October 2013

Academic Editor: Cornelia Vasile

Copyright © 2013 Arundhati Pal and A. K. Paul. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Extracellular polymeric substances (EPS) are complex biopolymers produced by a wide array of microorganisms for protection against dessication, aggregation, adhesion, and expression of virulence. Growth associated production of EPS by Ni-resistant Cupriavidus pauculus KPS 201 was determined in batch culture using sodium gluconate as the sole carbon source. The optimum pH and temperature for EPS production were 6.5 and 25°C, respectively. Optimal EPS yield (118 μg/mL) was attained at 0.35% Na-gluconate after 72 h of growth. Cupriavidus KPS 201 cells also utilized glutamate, acetate, pyruvate, fumarate, malate, malonate, formate, citrate, and succinate for EPS production. Although EPS production was positively influenced by the increase of nitrogen and phosphate in the growth medium, it was negatively influenced by nickel ions. Compositional analysis of the purified EPS showed that it is a homopolymer of rhamnose containing uronic acid, protein, and nucleic acid. Presence of lipids was also detected with spectroscopy. Non-destructive EPS mediated biofilm formation of KPS 201 was also visualized by epifluorescence microscopy.