the optimum nutrient supplement dose for improving Qp was determined as A1B1C3D3: Zn2+, 0.01;
Mg2+, 0.05; Mn2+, 0.04 and yeast extract, 9 g·L−1. According to the F value, the order of influence for
Qp value (Fyeast extract = 28.00, FMn
2+ = 3.88, FZn
2+ = 1.74 and FMg
2+ = 0.063) was similar to that of the
R value. The correlation between the predicted and actual results of the Qp value having R2 (92.07%)
higher than 75% confirmed that the fitted model to the results was acceptable [56].