Mixed-culture polyhydroxyalkanoate production from olive oil mill pomace.
Polyhydroxyalkanoate (PHA) was produced in bench-scale sequencing batch reactors (SBRs) fed olive pomace fermentate containing a mixed microbial consortium. Initial anaerobic fermentation in a sequencing batch fermentor (SBF) produced soluble carbon compounds, mainly organic acids. SBF effluent was centrifuged, removing solids, and fed into a SBR where intracellular PHA was produced. Buffer pre-treatment of diluted olive pomace increased organic acid production 75% in SBF fermentate over no pre-treatment. Hydraulic retention time (HRT), solids retention time (SRT), pomace concentration/dilution, and aerobic operation vs. anoxic/oxic cycling were studied to improve PHA formation. Maximum %PHA achieved was 39% (on a dry-weight cell basis), and the highest volumetric productivity was 0.042 g PHA/L-day under fully aerobic conditions. The highest PHA conversion yield was 0.3625 g PHA/L fermentate.
Department of Civil and Environmental Engineering, University of California, Davis, CA 95616, USA. jameslwaller@gmail.com
James L
JL
Waller
Peter G
PG
Green
Frank J
FJ
Loge
D000332:Aerobiosis; D001419:Bacteria / Q000378:metabolism*; D061249:Batch Cell Culture Techniques / Q000379:methods*; D019149:Bioreactors / Q000382:microbiology; D005285:Fermentation; D007220:Industrial Waste / Q000032:analysis*; D000069463:Olive Oil; D010938:Plant Oils / Q000737:chemistry*; D054813:Polyhydroxyalkanoates / Q000096:biosynthesis*
D007220:Industrial Waste; D000069463:Olive Oil; D010938:Plant Oils; D054813:Polyhydroxyalkanoates