Coriander seeds processing: Sequential extraction of non-polar and polar fractions using supercritical carbon dioxide extraction and ultrasound-assisted extraction

In this study, non-polar and polar compounds from coriander (Coriandrum sativum L.) seeds (CS) were fractionated using modern extraction techniques. CS were fractionated on nonpolar fraction using supercritical fluid extraction (SFE) and influence of mean particle size on yield and chemical profile was investigated. Results were compared with conventional techniques used in essential oil isolation. It has been shown that SFE has certain advantages comparing to traditional techniques in terms of extraction yield and selectivity, since it provided highest linalool content (877.07 mg/100 g CS). Raffinate exhausted by SFE could be suitable for further processing, and it was subjected to ultrasound-assisted extraction (uAE) of moderately polar and polar fraction of polyphenolic compounds. Results showed that ethanolic extracts had higher antioxidant activity than water extracts for all CS mean particle sizes. The highest content of hydroxycinnamic acids was observed in ethanolic extracts obtained from exhausted CS with lowest mean particle size. Therefore, coriander seeds, which have been known for its rich essential oil content, could be used for sequential production of polyphenolic-rich extracts with high antioxidant activity. (C) 2015 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.