Supercritical Fluid Extraction and Fractionation of Different Preprocessed Rosemary Plants

Abstract

Two-step supercritical fluid extraction of rosemary leaves at selected conditions of pressure and temperature is proposed to divide the oleoresin into two fractions with different antioxidant activities and essential oil compositions. Rosemary leaves obtained from different sources have been extracted and evaluated in terms of antioxidant activity and essential oil yield and composition. Also, a new device is proposed to improve the performance of the technique in terms of sample collection after SFE.

Supercritical Fractionation of Rosemary Extracts to Improve the Antioxidant Activity

“…In general, fractionation was accomplished by applying different conditions in two sequential extractions (sequential fractionation) or by producing a cascade decompression of the extract in two or more separator vessels (online fractionation). For example, Ibáñez et al [13] used sequential fractionation to isolate volatiles at 10 MPa and 313 K, while the antioxidant fraction was obtained at 40 MPa and 323 K without using a co-solvent. Ivanovic et al [20] employed a similar sequential fractionation scheme: A first fraction comprising the essential oils was extracted at a pressure of 11.5 MPa and 313 K, followed by the antioxidant fraction which was extracted at 30 MPa and temperatures in the range of 313-373 K.…”

Supercritical Fluid Extraction of Compounds from Spices and Herbs

“…Rosemary leaves obtained by different methods of drying have been submitted to SFE and antioxidant activity and volatile oil yield were evaluated, as well as the composition (Ibáñez et al 1999). Two main factors were considered: the drying process, which influences the volatile oil composition and therefore the extract quality, and the effect of the drying process on the plant cells.…”

“…Ibáñez et al (1999) applied the second approach to the fractionation of rosemary extract with two successive extraction steps, resulting in a volatile oil rich fraction with a low antioxidant activity in the first step (10 MPa and 313 K) and a high-antioxidant activity fraction in the second one (40 MPa and 333 K).…”

Green separation technologies in food processing: supercritical-CO2 fluid and subcritical water extraction

“…One of the most important considerations in developing new extraction processes is the safety aspect. In this sense, a variety of processes involving extractions with supercritical-CO 2 fl uid extraction, membrane-based separation, molecular distillation, and pressurized low-polarity water extraction, etc., are generally recognized as "green" separation technology and are considered clean and safe processes to meet requirements (Ibáñez et al 1999 ;Herrero et al 2006 ;Chang et al 2008 ) . They have been developed and are regarded as emerging innovative separation technologies that meet food quality and safety requirements.…”

“…It also has been exploited for the extraction of avoparcin in animal tissue (Curren and King 2001 ) , fungicides in agricultural commodities (Pawlowski and Poole 1998 ) , fragrances from cloves (Rovio et al 1999 ) , antioxidative components from sage (Ollanketo et al 2002 ) , anthocyanins and total phenolics from dried red grape skin (Ju and Howard 2005 ) , saponins from cow cockle seed (Güçlü-Üstündag et al 2007 ) , and other bioactive components from plant materials (Ong and Len 2003 ) . Some additional successful applications of this technique are for the extraction of essential oils from various plant materials (Khajenoori et al 2009 ;Mortazavi et al 2010 ) , sweet components from Siraitia grosvernorii , lactones from kava roots, antioxidant compounds from microalgae S. platensis (Ibáñez et al 1999(Ibáñez et al , 2003Herrero et al 2004Herrero et al , 2006 , and Ginkgo biloba and biophenols from olive leaves ( Japón-Lujána and Luque de Castro 2006 ) . Several comparison studies have been made between subcritical water extraction and traditional extraction such as by Soxhlet extraction.…”