Solid-state culture of Azospirillum brasilense: a reliable technology for biofertilizer production from laboratory to pilot scale

Bioprocess Biosyst Eng. 2021 Apr 15. doi: 10.1007/s00449-021-02537-3. Online ahead of print.ABSTRACTA biofertilizer of Azospirillum brasilense was produced in solid-state culture (SSC) from laboratory to pilot scale. Similar operation conditions (continuous aeration and mild intermittent mixing) and two dimensionless numbers with similar L/D ratio and a similar working volume were applied to reach a scale-up factor of 75. An innovative bioreactor with rotating helical ribbons (15 kg wet matter) was used at pilot scale. A mathematical model was proposed and validated to evaluate the respirometry trends at laboratory and pilot scale exhibiting similar behavior. The cell viability was (1.3 ± 0.4) × 109 and (1.3 ± 0.3) × 109 colony-forming units per gram of initial dry mass at laboratory and pilot scale, at 36 and 43 h, respectively. A. brasilense maintains its viability twelve months of storage at 4 and 30 °C. This is the first report of A. brasilense being cultivated in SSC under controlled conditions. SSC processes involving unicellular microorganisms with tolerance to agitation are a promising technology to produce biofertilizers.PMID:33860372 | DOI:10.1007/s00449-021-02537-3
Source: Bioprocess and Biosystems Engineering - Category: Biomedical Engineering Authors: Source Type: research