Preparation of partially purified biopolymer WD161
The seed culture of the selected strain with the highest
biopolymer yield was prepared in the selected medium (as
above) and inoculated (10%) into the fresh medium, then
incubated for 48 h. After centrifugation, polymer in the supernatant
was precipitated with cold acetone in the ration of
1:4 (supernatant:cold acetone), mixed well, centrifuged, then
dissolved the precipitate in deionized water and centrifuged
to remove insoluble materials. The supernatant was desalted
by dialysis (molecular weight cutoff, 8000 Da) against deionized
water at 4 C for 24 h with twice the amount of fresh
deionized water, and lyophilized to obtain partially purified
polymers (modified from Refs. [16], [17])