Optimization of microwave-assisted extraction technique for isolation of betulinic acid from Dillenia indica Linn. and its quantification using developed HPTLC method

Abstract

Modern extraction technique was investigated for the separation of betulinic acid from the bark of Dillenia indica Linn. Betulinic acid, a pentacyclic triterpenoid, is a potent anticancer compound and possesses other pharmacological actions. The objective of the present study was to investigate the optimum extraction conditions for betulinic acid using microwave-assisted extraction by applying response surface methodology based on three factors three levels Box-Behnken experimental design. The extraction was performed by considering three different independent variables: extraction temperature (70°C-90°C), microwave power (100 W), and extraction time (10-20 minutes) and quantified using developed High-performance thin layer chromatography method. The maximum yield of betulinic acid at optimized experimental conditions, i.e., 90°C, 200 W, 15 minutes was found to be 0.91%w/w. Analysis of variance showed that the "p-value" was 0.0004 which indicate that the models were statistically significant (p < 0.05). The value of the "coefficient of determination" (R2) for microwave-assisted extraction was 0.94 which indicate that the model shows the goodness of fit. To conclude, Microwave Extraction technique along with response surface design proved to be efficient compared to conventional methods which could be applied to isolate active constituents from plant sources.