کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6484081 158 2014 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
High production of poly-β-hydroxybutyrate (PHB) by an Azotobacter vinelandii mutant altered in PHB regulation using a fed-batch fermentation process
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بیو مهندسی (مهندسی زیستی)
پیش نمایش صفحه اول مقاله
High production of poly-β-hydroxybutyrate (PHB) by an Azotobacter vinelandii mutant altered in PHB regulation using a fed-batch fermentation process
چکیده انگلیسی
A mixed fermentation strategy based on exponentially fed-batch cultures (EFBC) and nutrient pulses with sucrose and yeast extract was developed to achieve a high concentration of PHB by Azotobacter vinelandii OPNA, which carries a mutation on the regulatory systems PTSNtr and RsmA-RsmZ/Y, that negatively regulate the synthesis of PHB. Culture of the OPNA strain in shake flaks containing PY-sucrose medium significantly improved growth and PHB production with respect to the results obtained from the cultures with the parental strain (OP). When the OPNA strain was cultured in a batch fermentation keeping constant the DOT at 4%, the maximal growth rate (0.16 h−1) and PHB yield (0.30 gPHB gSuc−1) were reached. Later, in EFBC, the OPNA strain increased three fold the biomass and 2.2 fold the PHB concentration in relation to the values obtained from the batch cultures. Finally, using a strategy of exponential feeding coupled with nutrient pulses (with sucrose and yeast extract) the production of PHB increased 7-fold to reach a maximal PHB concentration of 27.3 ± 3.2 g L−1 at 60 h of fermentation. Overall, the use of the mutant of A. vinelandii OPNA, impaired in the PHB regulatory systems, in combination with a mixed fermentation strategy could be a feasible strategy to optimize the PHB production at industrial level.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochemical Engineering Journal - Volume 82, 15 January 2014, Pages 117-123
نویسندگان
, , , , , ,