title: Production of poly-3-hydroxyalkanoic acids by a moderately halophilic bacterium, Halomonas marina HMA 103 isolated from solar saltern of Orissa, India.
abstract: Halomonas marina HMA 103 (MTCC 8968), the moderately halophilic bacterium isolated and characterized from the solar saltern of Orissa, India, grows optimally at 10% (w/v) NaCl in culture medium and is able to synthesize poly(3-hydroxybutyrate) [P(3HB)] during growth. This study is an attempt to optimize the cultural conditions for efficient production of P(3HB) by H. marina in batch cultivation. Growth of the organism under shake-flask culture using 2% (w/v) glucose resulted in P(3HB) accumulation accounting for more than 59% of cell dry weight after 50 h of incubation. The optimum P(3HB) production was attained with a combined supply of NH4Cl and yeast extract as N-source, 0.01% (w/v) phosphate, 1.5% (w/v) sulphate and 10% (w/v) NaCl. Qualitative and quantitative 1HNMR and FT-IR analysis of cells grown in alkanoic acids (C3-C6) as sole source of carbon and co-substrates revealed synthesis of PHA co-polymers composed of 3-hydroxybutyric acid and 3-hydroxyvaleric acid [P(3HB-co-3HV)]. In two-step cultivation, accumulation of the co-polymer was significantly improved (80% CDW) in glucose medium supplemented with valerate (0.1%, w/v) as co-substrate and the polymer contained 88.1 and 12.8 mol% 3HB and 3HV monomers, respectively.
authors.affiliation: Microbiology Laboratory, Department of Botany, University of Calcutta, Kolkata 700 019, India.
authors.forename: Amrita
authors.initials: A
authors.lastname: Biswas
authors.forename: A
authors.initials: A
authors.lastname: Patra
authors.forename: A K
authors.initials: AK
authors.lastname: Paul
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000378:metabolism*; D003470:Culture Media / Q000378:metabolism; D019015:Geologic Sediments / Q000382:microbiology; D044129:Halomonadaceae / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D007194:India
chemical_list: D003470:Culture Media; D020155:3-Hydroxybutyric Acid