Effects of nitrogen availability on polymalic acid biosynthesis in the yeast-like fungus Aureobasidium pullulans

Table 1 Effects of different levels of NH₄NO₃ on cell growth and PMA biosynthesis in shake flasks

NH₄NO₃ (g/L)	Residual sugar (g/L)	Cell biomass (g/L)	PMA (g/L)	Productivity (g/L h)	Yield (Y_P/X, g/g)	Yield (Y_P/S, g/g)
0.1	56.67 ± 0.50	6.23 ± 0.71	6.17 ± 0.29	0.06 ± 0.003	1.00 ± 0.137	0.18 ± 0.011
0.5	40.77 ± 0.12	13.09 ± 1.09	10.86 ± 1.91	0.09 ± 0.042	0.85 ± 0.246	0.25 ± 0.081
1.0	24.57 ± 0.31	17.17 ± 0.77	14.01 ± 0.04	0.15 ± 0.000	0.82 ± 0.037	0.21 ± 0.000
2.0	16.95 ± 1.91	21.31 ± 3.81	20.02 ± 2.81	0.21 ± 0.029	0.96 ± 0.242	0.24 ± 0.032
4.0	16.70 ± 0.35	23.55 ± 0.85	17.31 ± 0.24	0.18 ± 0.003	0.74 ± 0.024	0.24 ± 0.002
10.0	14.52 ± 0.58	24.20 ± 1.96	16.57 ± 0.90	0.17 ± 0.009	0.69 ± 0.081	0.22 ± 0.013

All the values are the means and standard deviations of three independent experiments. Yield (Yp/x): the ratio of PMA to cell biomass concentration (g/g); Yield (Yp/s): the ratio of PMA to consumed sugar concentration (g/g)

ISSN: 1475-2859