Optimization of Milk-Based Medium for Efficient Cultivation of Bifidobacterium pseudocatenulatum G4 Using Face-Centered Central Composite-Response Surface Methodology

Table 3

Regression analysis of the 2³ full factorial design with maximum biomass (log₁₀ cfu/mL) as the response.

Variable	𝐹 Value	𝑃 value
𝑥1^a	87.94	0.0007
𝑥2	6.40	0.0647
𝑥3	1.67	0.2658
𝑥1𝑥2	2.06	0.2246
𝑥1𝑥3	0.11	0.7572
𝑥2𝑥3	0.40	0.5623
𝑥1𝑥2𝑥3	0.07	0.8034
Model	14.09	0.0112
Curvature	3.94	0.1182
C.V = 2.78%	𝑅^2=0.96	Adjusted 𝑅^2=0.90

 ^a𝑥₁ represents skim milk concentration in % (wt/vol).
𝑥₂ represents yeast extract concentration % (wt/vol).
𝑥₃ represents glucose concentration % (wt/vol).