Optimization of microwave-assisted extraction of bioactive polyphenolic compounds from Marsilea quadrifolia L. using RSM and ANFIS modelling

Extraction of bioactive compounds, rich in plant secondary metabolites as a form of polyphenolic compounds has gained utmost important in the food and pharmaceutical industries due to their antioxidant properties. Microwave-assisted extraction (MAE) was utilized for maximum extraction of bioactive polyphenolic compounds from Marsilea quadrifolia L. with consuming less toxic solvent. A central composite rotatable design (CCRD) based on response surface methodology (RSM) and adaptive neuro-fuzzy inference system (ANFIS) were followed to design and optimize the experimental parameters to get highest yield of bioactive polyphenolic compounds from M. quadrifolia L. The quantitative effects of experimental parameters such as methanol concentration (X1), microwave power (X2), irradiation temperature (X3) and irradiation time (X4) were investigated to obtain the maximum yields of total phenolic (TPC), total flavonoid contents (TFC) and antioxidant properties. The optimum conditions were observed at methanol concentration (X1= 87.5 %), microwave power (X2= 25 %), irradiation temperature (X3= 60 ºC) and irradiation time (X4= 15 min). Under these conditions, the highest yields of TPC (y1)= 693.28 mg gallic acid equivalents (GAE)/g), TFC (y2)= 84.86 mg rutin equivalents (RU)/g), % DPPHsc (y3)= 81.06 %, %ABTSsc (y4)= 71.34% and FRAP (y5)= 68.09 μg mol (Fe (II)/g) has been attained. Further, the experimental results were highly acknowledged with predicted values of RSM and ANFIS. The analysis of LC-ESI-MS spectrum confirmed 6 major bioactive compounds, namely, Betasitosterol, Tridecyliodide, 2,3,7,8 tetracholorodibenzofuaran, Chlorogenic acid, Pentachlorophenylacetate and Triacontyl hexacosanoate in the optimized extract of M. quadrifolia L. The optimized extract can be used as an alternative of synthetic antioxidants for product manufacturing in food and pharmaceutical industries.