title: A one-stage cultivation process for the production of poly-3-(hydroxybutyrate-co-hydroxyvalerate) from olive mill wastewater by Haloferax mediterranei.
abstract: Olive mill wastewater (OMW), a highly polluting waste from the olive oil industry, was utilized as sole carbon source for the production of polyhydroxyalkanoate (PHA) by extremely halophilic Haloferax Mediterranei (H. mediterranei) in a one stage cultivation step. H. mediterranei showed remarkable cell growth and tolerated the inhibitory effect of polyphenols present in medium containing 25% of OMW. H. mediterranei cultivation conditions were optimized in medium containing 15% OMW by investigating several parameters that affect the production of PHA. The highest polymer yield (0.2g/L) and PHA content (43% PHA/cell dry mass) were achieved at 37°C, 170rpm and 22% salt concentration. Analysis of the produced PHA revealed the production of copolyester poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBHV) containing 6.5mol% 3-hydroxyvalerate (3HV). The production of PHBHV was observed without the need for fermentation step or adding external carbon source. The PHBHV displayed reduced melting points at 140.1°C and 154.4°C when compared to homopolymer polyhydroxybutyrate.
authors.affiliation: Scientific Research Center, Royal Scientific Society, Amman 11941, Jordan. Electronic address: Diya.safadi@rss.jo.
authors.forename: Diya
authors.initials: D
authors.lastname: Alsafadi
authors.affiliation: Scientific Research Center, Royal Scientific Society, Amman 11941, Jordan.
authors.forename: Othman
authors.initials: O
authors.lastname: Al-Mashaqbeh
mesh_terms: D019149:Bioreactors / Q000382:microbiology; D001709:Biotechnology; D019623:Haloferax mediterranei / Q000254:growth & development / Q000378:metabolism*; D031658:Olea; D011091:Polyesters / Q000737:chemistry / Q000378:metabolism*; D054813:Polyhydroxyalkanoates / Q000096:biosynthesis / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D062065:Wastewater / Q000737:chemistry*; D000094122:Polyhydroxybutyrates
chemical_list: D011091:Polyesters; D054813:Polyhydroxyalkanoates; D062065:Wastewater; C052620:poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate); D000094122:Polyhydroxybutyrates
keywords: Haloarchaea; Haloferax mediterranei; Olive mill wastewater; Poly(3-hydroxybutyrate-co-3-hydroxyvalerate); Polyhydroxyalkanoates