Low salt medium for lactate and ethanol production by recombinant Escherichia coli B

Individual nutrient salts were experimentally varied to determine the minimum requirements for efficient l(+)-lactate production by recombinant strains of Escherichia coli B. Based on these results, AM1 medium was formulated with low levels of alkali metals (4.5 mM and total salts (4.2 g l−1). This medium was equally effective for ethanol production from xylose and lactate production from glucose with average productivities of 18–19 mmol l−1 h−1 for both (initial 48 h of fermentation).