Supercritical Fluid Technology- An Unlimited Frontier in Herbal Research

Abstract

Supercritical fluid technology is a process using a supercritical fluid as a solvent. When a fluid is taken above its critical temperature (Tc) and critical pressure (Pc), it exists in a condition called the supercritical fluid state. The physico-chemical properties of a fluid in the supercritical state are in between those of a typical gas and liquid. Due to increasingly stringent environmental regulations, supercritical fluid technology (SFT) has gained wide acceptance in recent years as an alternative to conventional solvent extraction for herbal compounds as well as in many analytical and industrial processes. This article presents the practical aspects of SFT applications in selection of modifiers, on-line offline coupling techniques. SFT can also be used to clean up pesticides from herbal medicines. Carbon dioxide is most commonly used Supercritical Fluid (SF) as it is safe, inexpensive, non-toxic, non-inflammable and inert to most of the materials as well as its solvating strength is adjusted by modifier (methanol). SFT processes can be modeled to acquire useful information for better understanding of the extraction, mechanisms and optimization of the extraction procedures. In recent years, Supercritical Fluid Extraction (SFE) has emerged as a highly promising technology for production of herbal medicines and nutraceuticals with high potency of active ingredients.