Antioxidant Activities of the Supercritical and Conventional Satureja montana Extracts |
| |
Authors: | C Grosso AC Oliveira AM Mainar JS Urieta JG Barroso AMF Palavra |
| |
Affiliation: | Authors Grosso and Palavra are with Dept. de Engenharia Química e Biológica, IST, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal. Author Oliveira is with Dept. de Energias Renováveis, Inst. Nacional de Engenharia, Tecnologia e Inovação, Estrada do Paço do Lumiar 1649-038 Lisboa, Portugal. Author Urieta is with Dept. de Química orgánica y química física, Univ. Zaragoza, Pedro Cerbuna, 12, 50009 Zaragoza, Spain. Author Barroso is with Univ. de Lisboa, Faculdade de Ciências de Lisboa, Inst. de Biotecnologia e Bioengenharia, DBV, Centro de Biotecnologia Vegetal, C2, Campo Grande, 1749-016 Lisboa, Portugal. Direct inquiries to author Grosso (E-mail: ). |
| |
Abstract: | ABSTRACT: The antioxidant activities of the volatile and the nonvolatile fractions from Satureja montana obtained by supercritical fluid extraction (SFE) and by conventional techniques, hydrodistillation (HD) and soxhlet extraction (SE), were compared. A good agreement between DPPH and rancimat methods was obtained showing that the extracts were able to scavenge free radicals and to inhibit lipid oxidation. The volatile oil (obtained by SFE at 90 bar/40 °C) was the most effective extract, presenting the lowest EC50 (0.06 g/L) and the highest protector factor (PF = 2.03). These results demonstrated the advantages of SFE over conventional techniques by avoiding thermodegradation and hydrolysis reactions. Furthermore, volatile oil is 15 times richer in thymoquinone than the essential oil (HD). This compound is of great importance due to its antioxidant, neuroprotective, and anti-cancer activities. The combination of carvacrol + thymol + thymoquinone in volatile oil may be responsible for the increase in the antioxidant activity when compared to HD, which demonstrates that, in this case, SFE improves value to the final product. |
| |
Keywords: | hydrodistillation Satureja montana soxhlet extraction supercritical fluid extraction thymoquinone |
|
|