Extraction process, chemical profile, and biological activity of aromatic oil from agarwood leaf (Aquilaria sinensis) by supercritical carbon dioxide extraction

Agarwood leaf is a potential raw material for aromatic oil, yet it has lacked systematic research on the super-critical carbon dioxide (SC-CO2) extraction technique. In this study, aromatic oil from agarwood leaf was extracted by SC-CO2 extraction, hydrodistillation (HD), and Soxhlet extraction (SE), followed by a series of analysis. The kinetics models of SC-CO2 extraction were established with promising fitting quality. In aggregate, the yields, smells, and appearances of SC-CO2 extraction (45 celcius, 100 bar, 150 min) were better than the other two traditional extraction methods (SE and HD). Thirty and 18 constituents were identified by GC-MS and UPLC-QTOF-MS, respectively, which might explain the special aroma of agarwood leaf aromatic oil. Agarwood leaf aromatic oils contained abundant phenolic compounds and exhibited moderate antioxidant and AChE inhibitory activity, as well as significant anti-inflammatory and anti-melanogenesis activities. This work demonstrated that agarwood leaf aromatic oils extracted by SC-CO2 showed a great potential for developing as food additive or dietary supplement.