FIG. 2.

PHA accumulation by P. putida CA-3 when 2.0 g of styrene (A), phenylacetic acid (B), or glucose (C)/liter is supplied to 50 ml of growth medium containing 67 mg of nitrogen/liter. Biomass (in grams per liter) (♦), PHA accumulation (□), concentration of carbon source in the medium (in grams per liter) (▵), and nitrogen (supplied as sodium ammonium phosphate) concentration (in milligrams per liter) (▪) were all monitored over a 48-h period. All data are averages of results from at least three independent determinations. The concentrations of styrene in the growth medium and in the air above the growth medium were experimentally determined to be 0.02 and 0.004 g/liter, respectively, at time zero. While the concentration of styrene in the air above the medium remained at 0.004 g/liter throughout the growth curve, styrene was no longer detectable in the growth medium after time zero.