Abstract:

Response surface methodology was used to optimize the extraction process of seed oil from “Yanzhi” red radish
by supercritical CO2, and the fatty acid composition of the oil was determined. The Plackett-Burman design was used
to evaluate the influence of seven factors on extraction efficiency, and three important extraction parameters, including
extraction pressure, temperature and time, were selected. Steepest ascent path was adopted to approach the optimal response
region of the three significant factors, and then response surface analysis based on Box-Behnken design was used to
determine the optimal levels of the main factors. As a result, the optimal extraction conditions were established as follows:
the extraction was conducted at 34 MPa and 44 ℃ for 91 min. Under these conditions, the predicted and experimental extraction
rates of radish seed oil were 93.11% and (93.09 ± 0.80) %, respectively. The fatty acid composition of “Yanzhi” radish seed oil,
as determined by gas chromatography tandem mass spectrometry (GC-MS), was similar to that of rapeseed oil. The contents of
unsaturated and monounsaturated fatty acids in the radish seed oil were 89.01% and 67.50%, respectively.

Key words: response surface methodology, radish seed oil, “Yanzhi&rdquo, radish, supercritical CO2 extraction