Strategies for improved rhamnolipid production by Pseudomonas aeruginosa PA1

PeerJ

article

Alexandre Soares dos Santos¹  Nei Pereira Jr²  Denise M.G. Freire³ 

[1] Department of Basic Science/Faculty of Biological Science and Health, Universidade Federal dos Vales do Jequitinhonha e Mucuri;Department of Biochemical Engineering/School of Chemistry, Universidade Federal do Rio de Janeiro;Department of Biochemistry/Institute of Chemistry, Universidade Federal do Rio de Janeiro

关键词: Rhamnolipid;    Biosurfactant;    Pseudomonas aeruginosa;    Homoserine lactones;   

DOI  :  10.7717/peerj.2078

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Rhamnolipids are biosurfactants with potential for diversified industrial and environmental uses. The present study evaluated three strategies for increasing the production of rhamnolipid-type biosurfactants produced by Pseudomonas aeruginosa strain PA1. The influence of pH, the addition of P. aeruginosa spent culture medium and the use of a fed-batch process were examined. The culture medium adjusted to pH 7.0 was the most productive. Furthermore, the pH of the culture medium had a measurable effect on the ratio of synthesized mono- and dirhamnolipids. At pH values below 7.3, the proportion of monorhamnolipids decreased from 45 to 24%. The recycling of 20% of the spent culture medium in where P. aeruginosa was grown up to the later stationary phase was responsible for a 100% increase in rhamnolipid volumetric productivity in the new culture medium. Finally, the use of fed-batch operation under conditions of limited nitrogen resulted in a 3.8-fold increase in the amount of rhamnolipids produced (2.9 g L−1–10.9 g L−1). These results offer promising pathways for the optimization of processes for the production of rhamnolipids.

【 授权许可】

CC BY