Optimization of ethanol modified supercritical fluid extraction (SFE) of acetyl 11 keto β boswellic acid (AKBA) from Boswellia serrata using Box-Behnken experimental design

Acetyl 11 keto beta boswellic acid (AKBA), a potent anti-inflammatory agent obtained from Boswellia serrata oleogum resin, is mostly used for the treatment of various chronic inflammatory diseases. Ethanol modified supercritical fluid extraction (SFE) was employed to extract AKBA from Boswellia serrata. The optimal conditions for AKBA extraction were determined by Box-Behnken design which was employed to estimate the effect of three independent variables (pressure, extraction time and temperature) on the AKBA yield. The interactions between pressure with temperature and extraction time were found to be significant (p<0.05). The optimum conditions were found as pressure 26 MPa, extraction time 3.75 h (225 min) and temperature 54 degrees C using a constant CO2 flow rate of 3 mL/min. Under the optimum conditions, AKBA showed maximum extraction yield of 54.12 +/- 0.41 mg/g which was closer to the predicted yield. Ethanol modified SFE showed higher extraction yield as compared to batch extraction and ultrasound assisted extraction (UAE).