The fermentation broth obtained after isolation of the biomass was
filtered through a Whatman no. 1 filter paper. The samples were evaporated
under vacuum in a type R-II rotovapory (BUCHI, Switzerland) to
a one-third of their initial volume, and mixed with three volumes of 95%
v/v ethanol. Mixture was stirred vigorously and left at 4 °C over night
whereby the extracellular polysaccharides separated (Wu et al., 2014).
The obtained exopolysaccharides were collected from the surface and
washed several times with 95% ethanol (Lee et al., 2004). Lyophilisation
was preformed in a 1–4 LSC plus lyophilisator (CHRIST ALPHA,
Germany) to preserve the sample until use. For precipitation and estimation
of the EPS content, 20 mL of the fermentation broth were used
(Lee, Lee, & Lee, 1999). Measurements were conduced in triplicate and
the data are expressed as the mean value ± standard deviation.