Significance of oxygen supply in production of a novel antibiotic by Pseudomonas sp. SJT25.

A new agricultural antibiotic, 2-heptyl-5-hexylfuran-3-carboxylic acid (HHCA), was recently discovered, but its further application was limited due to its low production titer. In shake flask fermentation, the effect of initial K(L)a within the range of 2.12-18.87 h⁻¹ on HHCA production was investigated. The cell growth and glycerol consumption were faster at a higher initial K(L)a value, but the maximum production (14.43 mg/L) was attained at an initial K(L)a value of 12.46 h⁻¹. The oxygen supply information was further applied to a 2-L bubble column bioreactor (BCB) by varying initial K(L)a from 1.45 to 30.18 h⁻¹, and the hyperproduction of HHCA was achieved at a relatively low initial K(L)a around 5-10 h⁻¹. The control of oxygen supply is considered to be an important strategy to enhance HHCA production, and the information obtained will be useful to production of this powerful new antibiotic on a large scale.