Paramylon (β-1,3-glucan) content in wild type and WZSL mutant of Euglena gracilis.: Effects of growth conditions

The effects of growth conditions on paramylon (a beta -1,3-glucan reserve carbohydrate) content were examined in the photosynthetic wild-type and a spontaneous non-photosynthetic WZSL mutant of the unicellular flagellate Euglena gracilis. This carbohydrate is known to show interesting applications in human and veterinary medicine, as immunostimulant and immunopotentiator. For both strains, the synthesis of reserve depends mainly on the growth conditions, i.e. light or dark. The highest amount of paramylon is accumulated by the mutant (90% dry weight) under dark conditions and with glucose as the carbon source. These findings are discussed in terms of feasibility of exploitation of both strains as an alternative source of beta -glucan, and of the importance of the chloroplast compartment in the synthesis of this compound.