title: Enhanced production of histamine dehydrogenase by Natrinema gari BCC 24369 in a non-sterile condition.
abstract: The production of histamine dehydrogenase (HADH) by Natrinema gari BCC 24369, a halophilic archeaon isolated from fish sauce, was optimized and scaled up under a non-sterile condition. Through statistical design by Plackett-Burman design (PBD), casamino acid, NaCl, MgSO4·7H2O and FeCl2·4H2O were identified as the significant medium compositions influencing HADH production. Central composite design (CCD) was employed to identify the optimal values of individual composition yielding the maximum HADH production. The analysis indicated that the optimal medium was composed of 15 g/l casamino acid, 75 g/l MgSO4·7H2O, 273 g/l NaCl, 2.5 mg/l FeCl2·4H2O, 10 g/l yeast extract, 5 g/l sodium glutamate and 5 g/l KCl. Based on the one-factor-at-a-time (OFAT) method, the optimum initial pH of the culture medium and the incubation temperature for HADH production were 7.5 and 37 °C, respectively. The production of HADH under optimal conditions was 2.2-fold higher than that under un-optimized conditions. Owing to the halophilic nature of Nnm. gari BCC 24369, a more economical and eco-friendlier HADH production was developed under a completely non-sterile condition. In a 16-l batch cultivation of Nnm. gari BCC 24369, HADH productivity under a non-sterile condition (858 ± 12 U/g cell biomass) was comparable to that under a sterile condition (878 ± 15 U/g cell biomass). These results demonstrate the feasibility and simplicity of HADH production using Nnm. gari BCC 24369 under a non-sterile condition without compromising enzyme yield and any changes in Km value.
authors.affiliation: Department of Food Technology, Faculty of Agro-Industry, Prince of Songkla University.
authors.forename: Siriporn
authors.initials: S
authors.lastname: Chaikaew
authors.forename: Sorawit
authors.initials: S
authors.lastname: Powtongsook
authors.forename: Somphop
authors.initials: S
authors.lastname: Boonpayung
authors.forename: Soottawat
authors.initials: S
authors.lastname: Benjakul
authors.forename: Wonnop
authors.initials: W
authors.lastname: Visessanguan
mesh_terms: D003470:Culture Media / Q000737:chemistry*; D019605:Euryarchaeota / Q000201:enzymology* / Q000254:growth & development*; D006863:Hydrogen-Ion Concentration; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000378:metabolism*; D013696:Temperature
chemical_list: D003470:Culture Media; D000587:Oxidoreductases Acting on CH-NH Group Donors; C506665:histamine dehydrogenase