title: Optimization of cultural and nutritional conditions for accumulation of poly-beta-hydroxybutyrate in Synechocystis sp. PCC 6803.
abstract: Poly-beta-hydroxybutyrate (PHB) accumulation in the unicellular cyanobacterium, Synechocystis sp. PCC 6803, was studied under various cultural and nutritional conditions. Under controlled condition, cells harvested at the stationary phase of growth depicted maximum accumulation of PHB, i.e., 4.5% (w/w of dry cells) as compared to lag (1.8%) or logarithmic (2.9%) phases of cultures. A temperature range of 28-32 degrees C and pH between 7.5 and 8.5 were preferred for PHB accumulation. Cells cultivated under regular light-dark cycles accumulated more PHB (4.5%) than those grown under continuous illumination (2.4%). Nitrogen and phosphorus starvation stimulated PHB accumulation up to the tune of 9.5 and 11% (w/w of dry cells), respectively. Synechocystis cells pre-grown in glucose (0.1%)-supplemented BG-11 medium when subjected to P-deficiency in presence of acetate (0.4%), PHB accumulation was boosted up to 29% (w/w of dry cells), the value almost 6-fold higher with respect to photoautotrophic condition. Fishpond discharges were found as suitable media for PHB accumulation in the test cyanobacterium.
authors.affiliation: Agricultural and Food Engineering Department, Indian Institute of Technology, Kharagpur 721 302, India.
authors.forename: Bhabatarini
authors.initials: B
authors.lastname: Panda
authors.forename: Praveen
authors.initials: P
authors.lastname: Jain
authors.forename: Laxuman
authors.initials: L
authors.lastname: Sharma
authors.forename: Nirupama
authors.initials: N
authors.lastname: Mallick
mesh_terms: D017756:Aquaculture; D002244:Carbon / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry* / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration; D006885:Hydroxybutyrates / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism; D017440:Photoperiod; D011091:Polyesters / Q000378:metabolism*; D046939:Synechocystis / Q000145:classification / Q000187:drug effects* / Q000378:metabolism*; D013696:Temperature; D013997:Time Factors; D014865:Waste Disposal, Fluid; D000094122:Polyhydroxybutyrates
chemical_list: D002244:Carbon; D003470:Culture Media; D006885:Hydroxybutyrates; D009584:Nitrogen; D010758:Phosphorus; D011091:Polyesters; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates