过热水蒸气提取杉木精油及组成分析

Extraction of essential oil from Cunninghamia lanceolata by superheated water steam distillation

摘要:

杉木精油具有木香、膏香气息,具有重要的经济价值。而杉木精油的提取温度对精油的得油率及其成分有非常大的影响,随着提取温度升高,精油组成成分中沸点低的化合物减少,出现酸类物质,酸性气味出现。以杉木根屑为原料,过热水蒸气蒸馏(SSD)工艺提取杉木精油,条件为投料350 g,蒸气流量650 mL/h,蒸馏4小时,提取温度分别为130±5℃、160±5℃、190±5℃、220±5℃、250±5℃、280±5℃下提油。结果表明：过热水蒸气得率为常压水蒸气蒸馏(SD)的2-4倍。随着蒸气温度升高,精油中的柏木醇含量由49.99%下降到25.41%,α-柏木烯含量由16.61%上升至30.14%,β-柏木烯含量由4.10%上升至11.92%。通过SSD法提取杉木精油工艺可大大提高得油率,并且通过工艺的优化明确了精油中主要化学成分的组成及含量变化规律,明确温度满足产品的不同需求。

Abstract:

We developed a superheated steam distillation (SSD) strategy for the extraction of Chinese fir essential oil with Chinese fir root cuttings as raw materials. The conditions were listed as follows: feed 350 g, steam flow 650 mL/h, distillation for 4 hours, different extraction temperatures as 130 ± 5 ℃, 160 ± 5 ℃, 190 ± 5 ℃, 220 ± 5 ℃, 250 ± 5 ℃ and 280 ± 5 ℃ respectively. The results showed that the yield of superheated steam was increased 2-4 folds comparing with that of atmospheric steam distillation (SD). The essential oil of Cunninghamia lanceolata has the smell of wood and ointment. However, the compounds with low boiling point in the components of the essential oil decrease with the increase of extraction temperature. Also, acidic compounds were observed in the mixture with acidic smell. On the other hand, increasing the steam temperature led to the decrease of cedanol in essential oil from 49.99% to 25.41%, increase of α-cedrene from 16.61% to 30.14%, and increase of β-cedrene from 4.10% to 11.92%. This SSD strategy could dramatically improve the oil yield from Chinese fir essential oil. Furthermore, variation of the extraction temperature could provide the oil with different chemical components, which can meet the different needs of the product.