Development and Optimization of a Polyherbal Antidiabetic Formulation Containing Gymnema sylvestre, Momordica charantia, and Tinospora cordifolia Extracts Using D-Optimal Mxture Design and In Vitro Pharmacological Evaluation

Abstract

The present study aimed to develop and optimize a polyherbal antidiabetic formulation containing Gymnema sylvestre, Momordica charantia, and Tinospora cordifolia extracts using a D-optimal mixture design and to evaluate its in vitro pharmacological activities. Hydroalcoholic extracts of the selected plants were prepared and subjected to preliminary phytochemical screening and HPTLC standardization using gymnemic acid, charantin, and tinosporaside as marker compounds. A D-optimal mixture design consisting of sixteen experimental runs was employed to investigate the influence of extract proportions on various pharmacological responses, including α-amylase inhibition, α-glucosidase inhibition, advanced glycation end product (AGE) inhibition, and DPPH radical scavenging activity. The results demonstrated significant variations in biological responses depending upon the composition of the extracts. The optimized formulation containing 30% Gymnema sylvestre, 40% Momordica charantia, and 30% Tinospora cordifolia exhibited maximum α-amylase inhibition (85.1 ± 1.3%), α-glucosidase inhibition (91.6 ± 1.4%), AGE inhibition (83.8 ± 1.2%), and antioxidant activity (94.5 ± 1.1%). Statistical analysis confirmed the adequacy of the developed models, with excellent agreement between predicted and experimental values. The findings suggest significant synergistic interactions among the selected plant extracts and indicate that the optimized polyherbal formulation may serve as a promising natural therapeutic strategy for diabetes management and prevention of associated complications.