title: PHA productivity and yield of Ralstonia eutropha when intermittently or continuously fed a mixture of short chain fatty acids.
abstract: The research described in this present study was part of a larger effort focused on developing a dual substrate, dual fermentation process to produce Polyhydroxyalkanoate (PHA). The focus of this study was developing and optimizing a strategy for feeding a mixture of SCFAs (simulated ARF) and maximizing PHA production in a cost-effective way. Three different feeding strategies were examined in this study. The substrate evaluated in this study for the growth phase of R. eutropha was condensed corn solubles, a low-value byproduct of the dry-mill, corn ethanol industry. The culture was grown to high cell densities in nitrogen-supplemented condensed corn solubles media in 5 L bioreactors. The overall growth rate of R. eutropha was 0.2 h(-1). The 20 mL ARF feeding every 3 h from 48 to 109 h strategy gave the best results in terms of PHA production. PHA productivity (0.0697 g L(-1) h(-1)), PHA concentration (8.37 g L(-1)), and PHA content (39.52%) were the highest when ARF was fed every 3 h for 61 h. This study proved that condensed corn solubles can be potentially used as a growth medium to boost PHA production by R. eutropha thus reducing the overall cost of biopolymer production.
authors.affiliation: Department of Agricultural and Biosystems Engineering, South Dakota State University, Brookings, SD 57006, USA.
authors.forename: Panchali
authors.initials: P
authors.lastname: Chakraborty
authors.forename: Kasiviswanathan
authors.initials: K
authors.lastname: Muthukumarappan
authors.forename: William R
authors.initials: WR
authors.lastname: Gibbons
mesh_terms: D019149:Bioreactors / Q000382:microbiology; D002264:Carboxylic Acids / Q000378:metabolism; D020118:Cupriavidus necator / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism*; D000431:Ethanol / Q000378:metabolism; D005232:Fatty Acids, Volatile / Q000494:pharmacology*; D054813:Polyhydroxyalkanoates / Q000096:biosynthesis*; D003313:Zea mays / Q000737:chemistry
chemical_list: D002264:Carboxylic Acids; D005232:Fatty Acids, Volatile; D054813:Polyhydroxyalkanoates; D000431:Ethanol