Study of factors influencing pressurised solvent extraction of polar steroids from plant material. Application to the recovery of withanolides

Abstract

SummaryPressurisecl solvent extraction was applied to the extraction of three withanohcles from the leaves of Iochroma gesnerioides. A study was carried out of the influence of various parameters on the extraction efficiency and kinetic parameters; these included the nature of the extracting solvent, its flow rate, the pressure and temperature, as well as the particle size of the plant material. The pressurisecl solvent extraction method compared to a conventional Soxhlet extraction showed similar recoveries and extraction selectivity but the total handling time and solvent volume were dramatically reduced.

Extraction methods and chemical standardization of botanicals and herbal preparations

“…At higher temperature, the strong solute-matrix interaction caused by van der Waals forces, hydrogen bonding and dipole attractions between solute molecules and active sites on the matrix were disrupted. The used of pressurized solvent extraction of polar steroids, such as withanolides from the leaves of Lochroma gesnerioides and cocaine and benzylecgonine from coca leaves had been reported [39,40].…”

Protocols on safety, efficacy, standardization, and documentation of herbal medicine (IUPAC Technical Report)

“…Other than having the advantage of high extraction speed, MAE also enables a significant reduction in the consumption of organic solvents [71][72][73]. The use of PLE on polar steroids, such as withanolides from the leaves of Lochroma gesnerioides and cocaine and benzylecgonine from coca leaves has been reported [74,75]. To reduce the use of organic solvent, pressurized hot water extraction (PHWE) has been used for the extraction of essential oil components from plant materials [76,77].…”

Rapid liquid chromatographic-mass spectrometric analysis of withanolides in crude plant extracts by use of a monolithic column

“…It should be noted that although resolution between the two isomers was > 1.3, analysis time was excessively high (ca. 55 min) whereas extraction was performed in 40 s and 20 min with MAE and PSE, respectively [2,4].…”

“…To achieve high throughput each step must be optimized with special attention to time reduction. As a result, conventional Soxhlet extraction methods, which are tedious and time-and solvent-consuming, are nowadays being replaced by rapid extraction methods such as microwave-assisted extraction (MAE) [1,2] or pressurized solvent extraction (PSE) [3,4]. These methods have evolved as interesting alternatives to conventional methods and have drastically reduced sample-preparation times.…”

“…antibacterial, cytotoxic, or immunomodulating activity [17 21]. We have recently developed rapid methods, including MAE or PSE, for extraction of withanolides, resulting in significant time saving (a factor of ca 20) compared with conventional Soxhlet extraction [2,4]. The compounds were, however, analysed by liquid chromatography with UV detection, with excessively long analysis times (ca 60 min) [22,23].…”