title: Dynamic synthesis of polyhydroxyalkanoates by bacterial consortium from simulated excess sludge fermentation liquid.
abstract: The dynamic process of polyhydroxyalkanoates (PHA) synthesis by bacterial consortium in substrates simulating the excess sludge fermentation liquid was in-depth investigated in this study. The maximum PHA content and PHA yield was obtained with 62.43% of the dry cell and 0.71 g/L which is the highest under high initial carbon concentration (2170 mg TOC/L) and nitrogen-unlimited conditions so far. The active biomass growth presented an asynchrony with PHA synthesis under this hydrolysate-like condition. The consortium was prior to utilize even-number carbon acid to synthesize 3-hydroxybutyrate (HB) and then the odd-number carbon acid for 3-hydroxyvalerate (HV). Fermented liquid with higher percentage of volatile fatty acids (VFAs) is favor of a higher PHA content. Non-VFAs (>30%) such as protein and carbohydrates had negative effects on PHA accumulation but facilitated the cell growth. A balance should be found between cell growth and PHA accumulation in order to achieve a relative high PHA yield.
authors.affiliation: School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Jia
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.forename: Xiujin
authors.initials: X
authors.lastname: Wang
mesh_terms: D001419:Bacteria / Q000254:growth & development / Q000378:metabolism; D018533:Biomass; D002244:Carbon / Q000032:analysis; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005285:Fermentation; D007700:Kinetics; D059013:Microbial Consortia; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D054813:Polyhydroxyalkanoates / Q000096:biosynthesis*; D012722:Sewage / Q000382:microbiology*
chemical_list: D005232:Fatty Acids, Volatile; D054813:Polyhydroxyalkanoates; D012722:Sewage; D010758:Phosphorus; D002244:Carbon; D009584:Nitrogen