Comparison of microwave, ultrasonic and conventional techniques for extraction of bioactive compounds from olive leaves (Olea europaea L.)

Publication date: Available online 18 October 2019Source: Innovative Food Science & Emerging TechnologiesAuthor(s): Gabriela Silveira da Rosa, Sai Kranthi Vanga, Yvan Gariepy, Vijaya RaghavanAbstractThe aim of this study was to evaluate the effects of different extraction parameters on total phenolic (TP) compounds and antioxidant activity (AA) from olive leaves (Olea europaea L.) using microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and maceration. The study also emphasized on the optimization of MAE and UAE conditions, and on the potential benefits of using MAE as a pretreatment to UAE. It was demonstrated that olive leaves were a good source of phenolic compounds with high antioxidant activity. MAE at a higher temperature (86 °C) was more efficient in terms of TP yield, with short extraction time (3 min). MAE performed with water as a solvent was effective in disrupting the olive leaf cells thereby promoting the release of the compounds. Under this condition, the TP yield was increased by 82% when compared to maceration. In addition, it was demonstrated that MAE used as a pretreatment to UAE was more efficient.Industrial relevanceOlive leaves are usually considered as a residue with huge potential for value addition. High added-value compounds can be obtained by recovering phytochemicals from olive leaves for valorization through food products. The extraction of the bioactive compounds requires efficient techniques, but only a few studies sho...
Source: Innovative Food Science and Emerging Technologies - Category: Food Science Source Type: research