关键词: 牡丹籽, 微波提取, 中心复合设计, 响应面分析, GC-MS

Abstract:

Microwave was applied to the extraction of oil from Paeonia suffruticosa Andr. seeds. The extraction technique was optimized using response surface methodology. n-Hexane was selected as a optimal extraction solvent because compared to other solvents including petroleum ether (boiling range 30－60℃ or 60－90℃), ethyl acetate and acetone it yielded the most oil and can be easily penetrated by microwave. Effects of three crucial factors (i.e., liquid/material ratio, microwave power and extraction duration) on extraction yield of oil were investigated using one-factor-at-a-time design. Response surface central composition design in which the interactions between the variables were considered was applied to optimize these factors. A quadratic polynomial regression model was developed. The optimal microwave-assisted extraction conditions were as follows: liquid/material ratio (ml/g) 9:1, microwave power 825 W and extraction duration 8 min. Under such conditions, the actual oil yield was 24.52%, between which and the predicted value a relative error of about 0.01% was found. GC-MS Analysis indicated that the oil from Paeonia suffruticosa Andr. seeds was abundant in unsaturated fatty acids, in which the contents of linoleic acid and linolenic acid were 24.57% and 67.13%, respectively.

Key words: Paeonia suffruticosa Andr. seeds, microwave-assisted extraction, response surface analysis, GC-MS