Cristina Croitoru, Mariana Carmen Chifiriuc, Alexandru Mihai Grumezescu, Veronica Lazar: Optimization of culture conditions for the production and extraction of Klebsiella sp. and Pseudomonas sp. bacterial exopolysaccharides. Biointerface Research in Applied Chemistry, 3:619-627, 2013.
Exopolysaccharides (EPS) are extracellular polysaccharides produced by prokaryotic and eukaryotic microbial cells, with a variety of practical applications in medicine and pharmacy, due to their excellent properties such as high solubility and biodegradability, as well as susceptibility to chemical modifications to obtain the desired features for specific applications. The aim of this study was to optimise the experimental conditions for the extraction of EPS produced by Klebsiella sp. and Pseudomonas sp. strains. The amounts of the exopolysachharides accumulated in different fractions of bacterial cultures, i.e bacterial whole culture, sediment, and supernatant proved to be quite similar. The glucose supplementation of the liquid growth medium stimulated the production of the exopolysaccharidic material by Klebsiella pneumoniae and Pseudomonas aeruginosa strains. The EPS material could be extracted with good yields by using a cost-effective method allowing to obtain sufficient amounts of dry material required for further characterization and conditioning in micro-sized formulations for drug delivery.