Supercritical Fluid and Ultrasound-assisted Green Extraction Technologies for Catechin Recovery

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 bio-logically-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 CO2). Standalone SC-CO2 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.

Automated summary

Epimers of catechin are important bioactives with valuable health benefits, and efficient extraction methods such as supercritical fluid extraction can be preferred over ultrasound assisted extraction. Standalone SC-CO2 extraction shows higher selectivity and purity of product, making it a more suitable choice for extracting catechin.