Table 2.

Central composite design (CCD) for the production of PHAs.

Runs	Carbon Concentration (g/100 mL)	Nitrogen Concentration (g/100 mL)	PHA Content (g)
			Observed	Predicted	Residual
1	2	0.1	27.221	23.095	4.125
2	2	0.3	27.928	25.881	2.046
3	6	0.1	37.996	35.613	2.382
4	6	0.3	36.052	35.748	0.303
5	4	0.2	33.124	35.966	−2.842
6	0	0.2	2.25	4.228	−1.978
7	8	0.2	26.377	26.612	−0.235
8	4	0	29.38	31.526	−2.146
9	4	0.4	34.38	34.447	−0.067
10	4	0.2	34.38	35.966	−1.586