In this study, lipid fermentation wastewater (fermentation broth after separation with yeast biomass)
with high Chemical Oxygen Demand (COD) value of 25,591 mg/L was used as substrate for bacterial cellulose
(BC) production by Gluconacetobacter xylinus for the first time. After 5 days of fermentation, the
highest BC yield (0.659 g/L) was obtained. Both monosaccharide and polysaccharides present in lipid
fermentation wastewater could be utilized by G. xylinus simultaneously during fermentation. By this
bioconversion, 30.0% of COD could be removed after 10 days of fermentation and the remaining wastewater
could be used for further BC fermentation. The crystallinity of BC samples in lipid fermentation
wastewater increased gradually during fermentation but overall the environment of lipid fermentation
wastewater showed small influence on BC structure by comparison with that in traditional HS medium
by using FE-SEM, FTIR, and XRD. By this work, the possibility of using lipid fermentation wastewater
containing low value carbohydrate polymer (extracellular polysaccharides) for high value carbohydrate
polymer (BC) production was proven.