Bioprocess development as a sustainable platform for eco-friendly alkaline phosphatase production: an approach towards crab shells waste management

Table 2 Statistical analysis of Plackett–Burman design showing coefficient values, t- and p-values for each variable affecting ALP production

Variables	Coefficient	Main effect	Std Error	t-Stat	P-value	F-ratio	Contribution %	Confidence level (%)
Intercept	48.197		0.80246	60.06	3E⁻¹⁶			100
X₁	− 2.1520	− 4.30407	0.9149	− 2.352	0.0365	5.532	7.355	96.342
X₂	− 2.8354	− 5.6709	0.9149	− 3.099	0.0092	9.603	9.691	99.079
X₃	− 0.4216	− 0.84336	0.9149	− 0.4608	0.6531	0.212	1.441	34.687
X₄	0.1163	0.232652	0.9149	0.1271	0.9009	0.016	0.3976	9.9063
X₅	12.316	24.63205	0.9149	13.460	1.33E⁻⁰⁸	181.3	42.097	100
X₆	− 1.5704	− 3.14081	0.9149	− 1.7163	0.1117	2.945	5.367	88.822
X₇	− 2.864	− 5.72906	0.9149	− 3.1307	0.0086	9.801	9.791	99.132
X₈	0.2035	0.407141	0.9149	0.2224	0.8276	0.049	0.695	17.232
X₉	− 0.712	− 1.42499	0.9149	− 0.7787	0.4512	0.606	2.435	54.877
X₁₀	− 1.032	− 2.06479	0.9149	− 1.1283	0.2812	1.273	3.528	71.877
X₁₁	2.297	4.594881	0.9149	2.5109	0.0273	6.305	7.852	97.264
X₁₂	− 0.857	− 1.71581	0.9149	− 0.9376	0.3669	0.879	2.932	63.308
X₁₃	1.8757	3.751517	0.9149	2.0501	0.0628	4.203	6.411	93.714

ANOVA	Df	SS	MS	F	Significance F
Regression	13	3727.325	286.7173	17.1247	9.24E⁻⁰⁶	Std. Dev	3.18
Residual	12	200.9142	16.74285			Mean	48.20
Total	25	3928.239				C.V.%	6.60
R²	0.948					PRESS	355.56
Adj. R²	0.93					Adeq. Precision	26.85
Pred. R²	0.909					Multiple R	0.974

ISSN: 1475-2859