Clavulanic Acid Production by Streptomyces clavuligerus using Solid State Fermentation on Polyurethane Foam

Clavulanic acid (CA), a metabolite of Streptomyces clavuligerus, is a potent β-lactamase inhibitor. In this study, polyurethane foam (PUF) was used as inert solid support to produce clavulanic acid by solid state fermentation (SSF). Maximal CA yield of 263 μg/ml was obtained at pH 6.5, incubation temperature 29°C, 10 ml medium per 3 g PUF, 0.015% added glycerol, 2% added lithium chloride (LiCl), and 2 g/L added ornithine. Under the same conditions, the yield of CA produced by SSF on PUF is apparently higher than that by submerged fermentation (SMF). In addition, CA produced by using this method is of higher purity and easier to be extracted.