Ultrasonic-assisted rapid extraction of cassia sieberiana d.c.: a box-behnken design process optimisation

Abstract

Ultrasonic-assisted extraction (UAE) on the Cassia sieberiana root was optimised by a three-factor-three-level Box-Behnken design (BBD). A single factor experiment revealed the logic ranges for the UAE parameters for extraction time, temperature and solvent to sample ratio were 10-60 min, 30-60 C and 10-30 mL/g, respectively. The BBD showed that a second-order polynomial model produced a satisfactory fitting of the experimental data (R2 = 0.9917, P < 0.001) with regards to extraction yield. The optimal UAE conditions were 29 min, 45 C and 16.79 mL/g. Under the optimised conditions, the UAE yielded 1.28 ± 0.7% of C. sieberiana root extract as to 0.69 ± 1.1% obtained by maceration and 0.82 ± 0.5% obtained by Soxhlet extraction. The results affirmed that the BBD was suitable in establishing the optimum UAE conditions for a maximum extraction yield while being more efficient and rapid than conventional methods (maceration and Soxhlet extraction).