Production and optimization of bioplastic (Polyhydroxybutyrate) from Bacillus cereus strain SH-02 using response surface methodology

Table 3 ANOVA for Quadratic Model (Response 2: PHB concentration)

Source	Sum of Squares	Df	Mean Square	F-value	p-value
Model	1545.29	9	171.70	55.41	< 0.0001^a
A-glucose concentration	165.37	1	165.37	53.37	< 0.0001^a
B-peptone concentration	180.47	1	180.47	58.24	< 0.0001^a
C-pH	5.88	1	5.88	1.90	0.1985 NS
AB	3.58	1	3.58	1.15	0.3078 NS
AC	2.48	1	2.48	0.7989	0.3924 NS
BC	58.59	1	58.59	18.91	0.0014^b
A²	683.45	1	683.45	220.57	< 0.0001^a
B²	264.97	1	264.97	85.51	< 0.0001^a
C²	388.11	1	388.11	125.25	< 0.0001^a
Residual	30.99	10	3.10
Lack of Fit	22.83	5	4.57	2.80	0.1415 NS
Pure Error	8.15	5	1.63
Cor Total	1576.27	19
Std. Dev.	1.76
Mean	16.48
C.V. %	10.68
PRESS	194.13
R²	0.9803
Adjusted R²	0.9627
Predicted R²	0.8768
Adeq Precision	21.6548

ISSN: 1471-2180