Process optimization for extraction of bioactive compounds from taro (Colocasia esculenta), using RSM and ANFIS modeling

Abstract

Response surface methodology (RSM) and adaptive neuro fuzzy inference system (ANFIS) modeling was applied for optimization of process parameters for extraction of bioactive compounds from taro flour. A Face-centered central composite design (FCCD) was adopted to study the effects of process parameters on Total phenolic content (TPC), Total flavonoid content (TFC) and their antioxidant activity in terms of 1,1-Diphenyl-2-picryl-hydrazyl (DPPH), Ferric reducing antioxidant power (FRAP) and Total antioxidant activity (TAA) of taro flour. Three process parameters, solvent concentration, extraction temperature and extraction time were selected in range of 40–80% v/v, 30–60 °C and 1–5 h respectively. The optimum conditions for extraction of antioxidant from taro flour were obtained as solvent concentration 60% v/v, extraction temperature 48 °C and extraction time 4.0 h. Under these optimum conditions, the value of TPC, TFC, DPPH, FRAP and TAA were 14.17 mg GAE/100 g, 10.78 mg RE/100 g, 21.80%, 63.78 mg BHT Eq/100 g and 63.47 mg AAE/100 g with the desirability of 0.91. ANFIS model has been developed in terms of process parameters through Mamdani type fuzzy inference with triangular membership function for the prediction of responses using training data set. The results indicate that it rendered competitive results as obtained with RSM. Under the optimum conditions, experimental values were found close to the predicted values, obtained through RSM and ANFIS modeling. Liquid chromatography mass spectrometry (LCMS) analysis revealed that the caffeic acid, gallic acid, chlorogenic acid, catechin, epicatechin 3, 5 DiCQ acid and flavonols were the major compounds present in taro flour extract.