Abstract:

One-factor-at-a-time method (OFAT) and response surface methodology (RSM) were adopted to study the
effects of ethanol concentration, liquid/solid ratio, ultrasonic power and ultrasonic treatment time on the extraction yield of
proanthocyanidin from lotus seed pot (LSP). A multiple regression model was established to optimize the parameters for
ultrasonic-assisted extraction of LSP. The results indicated that ethanol concentration had the most significant impact on
the extraction yield of LSP, followed by liquid/solid ratio and ultrasonic power, while the impact of ultrasonic treatment
time was relatively low. When the extraction was carried out using 45% ethanol as the extractant at a liquid/solid ratio of
21:1 (mL/g) with ultrasonic treatment for 15 min at 700 W, the maximum yield of LSP of 6.81% was obtained, which was
close to the model-predictive value. Our results indicated that the developed model had good regression performance and
fitness, and could be applied in the prediction of the extraction yield of LSP. This study could provide scientific data for the
application of LSP as a natural antioxidant.

Key words: lotus seed pot, proanthocyanidins, extraction process, ultrasonic, response surface methodology