Bioactive compounds and cytotoxic activity of Lavandula dentata extract obtained via supercritical extraction

The flowers of Lavandula sp. have been widely studied and attributed to their therapeutic and aromatic properties. However, no apparent study to date has examined the extraction of Lavandula dentata compounds from supercritical extraction with CO₂ solvent, a technique recognized for efficiency, selectivity, and ability to generate extracts without solvent residues. The aim of this study was to determine the cytotoxic potential of volatile compounds of L. dentata, extracted by supercritical technology and cytotoxic and antioxidant capacity examined using human cervical (SiHa) and hepatic tumor cells (Huh7.5). Supercritical fluid extraction was conducted under conditions of 180 bar, 40°C and carbon dioxide (CO₂) solvent flow rate of 1.06 × 10^-4 kg/sec. A yield of 1.68 ± 0.04% by mass was obtained. The major bioactive compounds detected by GC-MS were camphor and 1,8-cineol (oxygenated monoterpenes). The high presence of phenolic compounds was detected through the Folin-Ciocalteu test consequent potential of antioxidant capacity through DPPH inhibition. A high number of total carotenoids were identified, an unprecedented result for this species. The MTT cytotoxicity tests with SiHa and Huh7.5 cell lines were promising at concentrations of 200 to 1000 μg/ml at 24, 48 or 72 hr. Evidence indicates that supercritical extraction with CO₂ solvent was efficient in extraction of phenolic compounds and carotenoids as well as enhancing antioxidant capacity, which confer promising beneficial biological activities for human health.