Extraction of Corymbia citriodora essential oil and resin using near and supercritical carbon dioxide

Abstract Corymbia citriodora essential oils (EO) from the two major distilleries of Brazil were compared with those obtained by supercritical fluid extraction (SFE) using CO 2 . Resin extracts (R) from the leaves exhibiting bioactivity were also obtained in a sequential and selective extraction process. Chemical composition analysis of the EOs obtained by steam distillation (SD), hydro distillation (HD) and CO 2 extraction of C. citriodora leaves from Sao Paulo showed higher Citronellal Content (CC) compared to those from Minas Gerais region. Also, SFE provided the highest quality of extracts and higher citronellal content compared to the more conventional SD and HD methods. In addition, this single process was based on two steps to obtain two different products. Near-critical CO 2 was used for extraction of essential oils, since these conditions promote the volatiles extraction. When exhausted the essential oil, the same leaves into the extractor was subjected to supercritical CO 2 conditions and a new product was obtained, the resin. In this process it was possible to obtain high quality EO and R with high antioxidant potential.