Supercritical Fluid and Ultrasound‐assisted Green Extraction Technologies for Catechin Recovery
Sayantani Dutta, S. Priyadarshini, J.A. Moses, C. Anandharamakrishnan
Abstract
Abstract The epimers of catechin include epicatechin, epigallocatechin and epigallocatechin gallate, and others. They are important bioactives that have salutary effects, and hence are valuable. For ascertaining biologically‐safe and green extraction methods that are non‐thermal, this review evaluates the efficiencies of ultrasound assisted extraction (UAE) and supercritical (SC) fluid extraction (with CO 2 ). Standalone SC‐CO 2 could be preferred over UAE, given its selectivity (purer product, no co‐extracts) and absence of downstream processing. GRAS solvents as water and ethanol or a hydro‐alcoholic mix are preferable for UAE. However, considering the core competency of ultrasound in disrupting cell organelles, a tandem approach with sequential SC extraction is recommended to justify process economics and ensure quality yield of catechin using green technologies.