Towards PHA Production from Wastes: The Bioconversion Potential of Different Activated Sludge and Food Industry Wastes into VFAs Through Acidogenic Fermentation

Acidogenic fermentation of wastes produces volatile fatty acid (VFA)-rich streams that can be used as low-cost carbon sources for polyhydroxyalkanoate (PHA) production. In this study, an inoculum collected from anaerobic reactor a municipal WWTP was conditioned to suppress methanogenic activity. The heat-shock conditioning method the proved more efficient than and alkaline methods methanogens inhibition. Then, pre-conditioned determine acidogenic potential different wastes: three waste activated sludge (WAS) samples generated at retention times (SRTs, 2, 7 14 days), olive mill wastewater (OMW), glycerol, apple pomace (AP) winterization oil cake (WOC). Batch tests were performed in quintuplicate 37 °C pH 7. A higher degree acidification observed high-rate (2 days SRT) (69%), followed by (OMW) (43%), while lowest glycerol (16%). results (WOC) interestingly elucidated high content propionic with odd-to-even ratio (0.86) after fermentation. Feeding VFA profile obtained WOC into PHA production system led significant 0.64 g g?1 C 30% polyhydrobutyrate (PHB) 69% polyhydroxyvalerate (PHV) monomeric units HB-co-HV, decoupling need related source co-polymer