Optimization of extraction conditions of pepper stems essential oil and its composition analysis.

Pepper stems essential oil was extracted from pepper stems by enzymatic assisted steam distillation using cellulase as extractant. The four factors affecting the yield of essential oil (enzyme concentration, enzyme treatment time, enzyme treatment temperature and liquid-solid ratio) were optimized by single factor test and response surface methodology. The experimental results showed that: the best yield of pepper stems essential oil was 1.21%±0.02% when the enzyme concentration was 103.25 g/L, the enzyme treatment temperature was 41.28°C, the enzyme treatment time was 3.01 h, and the liquid-to-material ratio was 5.23:1, which was 51.25% higher than that of steam distillation under the same conditions. The components of pepper stems essential oil were analyzed and identified by GC-MS. The results showed that: there were 47 chemical substances in pepper stems essential oil, mainly containing monoterpenes, sesquiterpenes, aromatic hydrocarbons, alcohol compounds, ester compounds, etc. Its composition was mainly enterpenoids, and the components with the...