Optimization of medium components for the production of PLA by the strain Lactobacillus sp. SK007, which was isolated from Chinese traditional pickles. was carried out using response surface methodology (RSM) based on a uniform design and a central composite rotatable design (CCRD). The final concentration of the optimized medium was 30 g L(-1) glucose, 5 g L(-1) phenylpyruvic acid (PPA), 47 g L(-1) corn steep liquor, 3 g L(-1) K(2)HPO(4), 3 g L(-1) CH(3)COONa, 30 g L(-1) yeast powder and 3 mL L(-1) Tween-80. A maximum PLA yield of 2.30 g L(-1) was achieved, which was significantly higher than previously reported. (C) 2008 Elsevier Ltd. All rights reserved.