超临界CO_2萃取及气质联用分析沙枣花精油成分

Gas Chromatographic-Mass Spectrometric Analysis of Essential Oil Extracted by Supercritical CO_2 from Flowers of Elaeagnus angustifolia L.

根据Box-Behnken试验设计原理,采用三因素三水平的响应面分析法对沙枣花精油进行超临界CO2流体萃取研究。结果表明,超临界CO2流体萃取沙枣花精油的最佳工艺条件为:萃取压力3400psi(23.45MPa)、萃取温度58℃、萃取时间4h,沙枣花精油萃取得率达到2.41‰。通过气质联用技术对超临界CO2萃取得到的沙枣花精油进行分析,鉴定出26种化合物。萃取物中含量最高的化合物是肉桂酸乙酯,其次为9-十八烯酸乙酯,再次是软脂酸,相对含量较高的化合物还有乙酸丙酯、2-炔十五醇和9-十八烯醛等。可以确定肉桂酸乙酯是沙枣花精油的主要成分,与芳香醇及酮类等对香气可能有贡献。

The optimal conditions for supercritical CO2 extraction of essential oil from fresh flower of Elaeagnus angustifolia L were explored by response surface methodology（RSM）.A three-level Box-Behnken factorial design was used to investigate the effects of three independent variables such as extraction pressure,extraction temperature and extraction time on the yield of essential oil.Results showed that the optimal extraction process conditions for supercritical CO2 extraction of essential oil from fresh flower of Elaeagnus angustifolia L.included extraction pressure of 3400 psi（23.45 MPa）,extraction temperature of 58 ℃,and extraction duration of 4 h.Under these extraction conditions,the yield of essential oil was up to 2.41‰.Meanwhile,26 compounds were identified in the extract by GC-MS.Among them,ethyl cinnamate was the most dominant followed by（E）-9-octadecenoic acid ethyl ester and n-hexadecanoic acid.In addition,relatively high amounts of n-propyl acetate,2-pentadecyn-1-ol and 9-octadecenal（Z） were also found in the extract.Apart from ethyl cinnamate,aromatic alcohols and ketones appeared to contribute to the aroma of the essential oil.