Use of a mannitol rich ensiled grass press juice (EGPJ) as a sole carbon source for polyhydroxyalkanoates (PHAs) production through high cell density cultivation

• Published in: Bioresource technology 2015-09, Vol.191, p.45-52
• Main Authors: Cerrone, Federico, Davis, Reeta, Kenny, Shane T., Woods, Trevor, O’Donovan, Anthonia, Gupta, Vijai Kumar, Tuohy, Maria, Babu, Ramesh P., O’Kiely, Padraig, O’Connor, Kevin
• Format: Article
• Language: English
• Subjects: Bacteria - metabolism; Batch Cell Culture Techniques - methods; Biorefining; Carbon - metabolism; Cell Count - methods; Ensiled grass press juice; Mannitol; Mannitol - metabolism; Poaceae - metabolism; Polyhydroxyalkanoates; Polyhydroxyalkanoates - metabolism; Pulse feed
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2015.04.128

[Display omitted] •First report on the use of a mannitol rich renewable carbon source for PHA production.•Achieved PHB and mcl-PHA production using EGPJ as sole carbon source.•EGPJ is a suitable substrate to achieve high cell density and high PHB productivity.•PHB productivity on EGPJ was comparable to that on commercial sugars. This study demonstrates the use of a mannitol rich ensiled grass press juice (EGPJ) as a renewable carbon substrate for polyhydroxyalkanoates (PHA) production in shaking flask experiments and fed-batch stirred tank reactor cultivations. Fed-batch cultivations of Burkholderia sacchari IPT101 using EGPJ as sole carbon source produced 44.5g/L CDW containing 33% polyhydroxybutyrate (PHB) in 36h, while Pseudomonas chlororaphis IMD555 produced a CDW of 37g/L containing 10% of medium chain length polyhydroxyalkanoates (mcl-PHA) in 34h. PHB and mcl-PHA extracted from B. sacchari IPT101 and P. chlororaphis IMD555, grown on EGPJ, had a molecular weight of 548kg/mol and 115.4kg/mol, respectively. While mcl-PHA can be produced from EGPJ, PHB production is more interesting as there is a 4-fold higher volumetric productivity compared to mcl-PHA.