engleski

Production of beta-1, 3- glucan by heterotrophic cultivation of Euglena gracilis

Unicellular algae Euglena gracilis is one of the most interesting organism for industrial production of beta-1, 3-glucan (paramylon). In heterotrophic conditions, E. gracilis has capability to accumulate intracellularly large amounts of paramylon. Therefore, it could be used as an alternative source of b-glucan to Saccharomyces cerevisiae, currently industrially exploited for its extraction. Paramylon (as a linear polysaccharide) has positive effect on human health and it is mostly used in medicine as an immunostimulant and immunopotentiator. The aim of this research was to enhance yield of Euglena gracilis biomass and paramylon by cultivating cells in synthetic and complex [containing different components such as potato liquor, concentrated potato liquor, molasses, corn steep solid, yeast extract etc.] media and to improve the recovery of paramylon. In this investigation comparison between different cultivation techniques (batch, fed batch and repeated batch) was also done. During this research following cultivation parameters were monitored: biomass dry weight, cell number, sugar and paramylon concentrations, dry metter of medium, C and N content of medium. On the basis of obtained results it can be concluded that complex medium with potato liquor is the most adequate medium for E. gracilis cultivation. In this research, paramylon content in dry biomass was up to 80 %. Repeated batch technique is the most adequate cultivation technique for industrial paramylon production because of the highest obtained yields and productivities during these cultivations. In this investigation, successful procedure for paramylon isolation and purification was also established.

beta-1; 3-glucan (paramylon); Euglena gracilis; heterotrophic cultivation; synthetic and complex media; paramylon recovery

nije evidentirano