Extraction of essential oils from crown daisy and dandelion

Abstract

Plants within the Asteraceae family are renowned for their culinary and medicinal values. In fact in Malta, 15 % of the flowering plants belong to this plant family. The two plant species studied were namely the Crown Daisy ( Glebionis coronaria) and Dandelion (Taraxacum officinale), both of which are abundantly found during early Spring. Two extraction methods were employed during this study: steam distillation and solvent extraction. Briefly, from steam distillation three types of extracts were obtained, i.e. the essential oil, the distillate and the decoction, while for solvent extraction, ethanol was employed as solvent. The extracts obtained were analysed using two well-known techniques, i.e. Ultraviolet spectrophotometry and Thin-layer chromatography. All extracts were analysed by UV and a particular trend was observed. TLC was then performed on the essential oils, where the most prominent volatile constituents were qualitatively idenitified. Apart from the dandelion flowers-TLC analysis, it was observed that in the UV scans, the flowers revealed higher amounts of constituents when compared to the leaves. In regards to the UV readings, the flowers have higher peaks than those of the leaves. This clearly illustrates that the flower is the plant part that is worth investing as it offers far more essentials than any other part of the plant.