3.4. Further optimization of the nutrients using Taguchi methodology
Based on the results of Plackett–Burman design, four variables including initial pH, incubation temperature, KH2 PO4 and Ca2+ ,
which significantly influenced inulinase production, were further
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investigated for their optimum combination using Taguchi’s (L9 34 ) orthogonal array design. The design and results of the experiments together with the predicted activity from the regression equation for the combinations are shown in (Table 3). It showed that the actual response values agree well with the predicted response val-ues.