Optimization of culture conditions for exopolysaccharides production in Rhizobium sp. using the response surface method

• Published in: Electronic Journal of Biotechnology 2006-07, Vol.9 (4)
• Main Authors: Duta, Flávia Pereira, de França, Francisca Pessôa, Lopes, Léa Maria de Almeida
• Format: Article
• Language: English
• Subjects: exopolysaccharides, experimental design, response surface method, Rhizobium sp
• ISSN: 0717-3458; 0717-3458
• DOI: 10.2225/vol9-issue4-fulltext-7

The combined effects of the processing parameters for exopolysaccharides production by Rhizobium sp. was studied using the experimental design and response surface methodology. The experiments were carried out using a fermenter with 20 L capacity, as the reactor. All processing parameters were online monitored. The temperature [(30 ± 1)°C] and pH value (7.0 ± 0.1) were kept constant throughout the experimental time. As statistical tools, a complete 23 factorial planning with central point and response surface were used to study the interactions among three relevant variables of the fermentation process: calcium carbonate concentration, aeration and agitation. The processing parameters setup for reaching a maximum response for exopolysaccharides production was obtained when applying the highest values for calcium carbonate concentration (1.1 g/L), aeration (1.3 vvm) and agitation (800 rpm). In addition, the combination of these optimum processing parameters yielded YP/S (g/g) = 0.35.