Pulsed electric fields for extraction of secondary metabolites from plants

Abstract

Many plants contain substances of biological and technological value which require the use of exhaustive, expensive, and environmentally unfriendly recovery methods to isolate them. The inaccessibility of these valuable compounds is often a function of the fact that they are contained within plant cells from which they must be released prior to isolation. A variety of methods have been developed and applied to facilitate the release of intracellular components; however, many of these are expensive and time-consuming. An alternative for this method is pulsed electric fields (PEF). PEF is as an effective technology for permeabilization of cell membranes from many natural sources and can thus aid in the extraction of secondary metabolites from plant materials. This technology presents several advantages that make it a suitable technology for this purpose. For example, it is a nonthermal technology with low energetic cost that can be applied to fresh material and with a relative easy implementation in the existing processing lines. The growing interest in secondary metabolites due to their biological and technological value has increased the interest in applying PEF for improving the extraction process of these compounds. The application of PEF to a new plant matrix with the purpose of improving the extraction of metabolites requires to consider several factors, from the processing parameters to the extraction process that will have an impact on the final result. By answering a number of questions, this chapter aims to give a rough guide of these parameters that have to be considered by the future researchers who are aiming to develop a new protocol for extraction metabolites from plants assisted by PEF.