Print Email Facebook Twitter Calcium enhances polyhydroxyalkanoate production and promotes selective growth of the polyhydroxyalkanoate-storing biomass in municipal activated sludge Title Calcium enhances polyhydroxyalkanoate production and promotes selective growth of the polyhydroxyalkanoate-storing biomass in municipal activated sludge Author Estevez Alonso, A. (TU Delft BT/Environmental Biotechnology; Wetsus, Centre for Sustainable Water Technology) Arias-Buendía, María (Wetsus, Centre for Sustainable Water Technology) Pei, R. (TU Delft BT/Environmental Biotechnology; Wetsus, Centre for Sustainable Water Technology) van Veelen, H. Pieter J. (Wetsus, Centre for Sustainable Water Technology) van Loosdrecht, Mark C.M. (TU Delft BT/Environmental Biotechnology) Kleerebezem, R. (TU Delft BT/Environmental Biotechnology) Werker, A. (Wetsus, Centre for Sustainable Water Technology) Date 2022 Abstract Activated sludge from municipal wastewater treatment processes can be used directly for the production of biodegradable polyesters from the family of polyhydroxyalkanoates (PHAs). However, municipal activated sludge typically cannot accumulate PHAs to very high levels and often low yields of polymer produced on substrate are observed. In the present work, it was found that the presence of calcium promotes selective growth and enrichment of the PHA-storing biomass fraction and significantly improved both PHA contents and yields. Calcium addition resulted in PHA contents of 0.60 ± 0.03 gPHA/gVSS and average PHA yields on substrate of 0.49 ± 0.03 gCODPHA/gCODHAc compared to 0.35 ± 0.01 gPHA/gVSS and 0.19 ± 0.01 gCODPHA/gCODHAc without calcium addition. After 48 h, three times more PHA was produced compared to control experiments without calcium addition. Higher PHA content and selective biomass production is proposed to be a consequence of calcium dependent increased levels of passive acetate uptake. Such more efficient substrate uptake could be related to a formation of calcium acetate complexes. Findings lead to bioprocess methods to stimulate a short-term selective growth of PHA-storing microorganisms and this enables improvements to the techno-economic feasibility for municipal waste activated sludge to become a generic resource for industrial scale PHA production. Subject CalciumCalcium acetatePolyhydroxyalkanoate (PHA)Simultaneous growth and accumulationWaste activated sludge To reference this document use: http://resolver.tudelft.nl/uuid:228362d3-62c6-45ad-a5e8-8ba34282742e DOI https://doi.org/10.1016/j.watres.2022.119259 ISSN 0043-1354 Source Water Research, 226 Part of collection Institutional Repository Document type journal article Rights © 2022 A. Estevez Alonso, María Arias-Buendía, R. Pei, H. Pieter J. van Veelen, Mark C.M. van Loosdrecht, R. Kleerebezem, A. Werker Files PDF 1_s2.0_S0043135422012040_main.pdf 1.74 MB Close viewer /islandora/object/uuid:228362d3-62c6-45ad-a5e8-8ba34282742e/datastream/OBJ/view