Optimization of an Antihyperglycemic Triherbal Formulation using Response Surface Methodology

Abstract

The present study was aimed to optimize the combination of methanolic extracts of <em>Salvia hispanica</em>, <em>Chenopodium quinoa </em>and <em>Nelumbo nucifera </em>seeds for developing an anti-hyperglycemic triherbal formulation with multifunctional potentials based on Response Surface Methodology using central composite design. A three- level factorial design was applied to determine the combined effect of three independent variables (<em>S.hispanica</em>:A;<em>C. quinoa</em>:B and <em>N.nucifera</em>: C) on inhibition of four responses (α- amylase: R1; α-glucosidase:R2; DPPH:R3 and Lipase:R4). The three factors were coded at five levels (−α, −1, 0, +1 and + α), which resulted in 20 experimental runs. The optimum concentration showing α-amylase (79.51%), α-glucosidase (82.97%) and lipase (70.47%) inhibitory activities with DPPH (83.47%) scavenging potential was found to be 1 mg/ml. A quadratic polynomial equation was found to best fit the model with α-amylase R² = 0.891, α-glucosidase R²= 0.911, DPPH R²= 0.904 and lipase R²= 0.915. The lack-of-fit values were insignificant (<em>p </em>> 0.05) for all four second-order equation. The analytical method was validated and the results were found closer to the predicted values. The optimized formulation was chosen further to develop the triherbal antihyperglycemic formulation.