2.4.4. BC purification and quantification
After the incubation period, the BC membranes were withdrawn
from the culture media and treated with NaOH
0.5 mol dm3 at 90 C for 30 min. This procedure was repeated
three times in order to eliminate attached cells [33]. Then, the
membranes were washed with distilled water to remove
components of the culture media and other residues until its
whitening and reaching pH 7.0. Finally, the purified BC
membranes were dried at 105 C to constant weight and the
concentration was determined in g L1 (mass (g) of BC/volume
(L) of culture medium).