TABLE 3.

P(4HB) homopolymer synthesis during three-step cultivation of H. pseudoflava^a

Culture step	Dry cell wt (g/liter)	Polyester content (%, wt/wt)	Polyester composition (mol%)b
			3HB	4HB
First	1.94 ± 0.08	10.1 ± 0.6	100
Second	1.68 ± 0.07	NDc
Third	2.42 ± 0.06	19.6 ± 0.5		100

^aThe second-step carbon-free medium contained 0.3 g of ammonium sulfate per liter. The P(3HB)-free cells recovered were transferred to γ-butyrolactone-containing PHA synthesis mineral medium (the third culture). Duplicate experiments were carried out. 

^bCalculated from gas chromatographic data. 

^cND, not detected by gas chromatographic analysis.