Optimisation of medium composition for clavulanic acid production by Streptomyces clavuligerus

Among four different commercially available nitrogen sources containing soy bean derivatives, a protein extract of soybean gave the highest yield for c lavulanic acid production by Streptomyces clavuligerus. A statistical metho d based on factorial design of experiments was applied to optimise the medi um. An empirical model was obtained by applying response surface statistica l analysis. The analysis of variance showed that concentrations of protein extract of soybean and glycerol and the interaction between these two varia bles were significant at 95% level of confidence. The maximum clavulanic ac id concentration obtained in 72 h was 1.2 g l(-1).