Obtaining bioactive compounds from clove and rosemary using supercritical technology: influence of the bed geometry, process intensification and cost of manufacturing of extracts

Abstract

The Supercritical Fluid Extraction (SFE) of plants is a process with increasing technological advancement on physics separations fields in the latest years. Most of studies evaluate the extracts composition testing different temperatures and pressures of extraction. However, a few searches evaluate the performance of process testing the bed geometry effect, in order to propose the scale up and the industrial application. In this context, the aim of the present work is to carry out SFE assays at laboratory scale equipment (SFE-2×1L) formed by two 1 L extraction vessels with different bed geometries, making a technical and an economical evaluation. The kinetic behavior of the extraction curves obtained from the assays on different extractors will allow establishing the best design using CO2 and clove (Eugenia caryophyllus) as a raw material model. The equipment will be modified to contain two 1 L extraction vessels with equal bed geometries, regarding the best design. After the laboratory scale equipment validation, the rosemary (Rosmarinus officinalis) will be used to focus simulating a continuous extraction process evaluating, as well, the scale up. Further, the extraction of natural antioxidants will be performed with pressurized liquid water. The hydrolysis of the residue from SFE will be tested with objective to reuse the biomass. The chemical analysis of the extracts will be determined using Thin Layer Chromatography (TLC) and Gas Chromatography (GC-FID). The content of phenolic diterpenes present on rosemary extract will be determined using spectrophotometer UV-vis. The antioxidant activity of rosemary extracts will be analyzed by the coupled reaction of linoleic and Beta-carotene. The products of hydrolysis will be analyzed by Supercritical Fluid Chromatography (SFC) and/or High Performance Liquid Chromatography (HPLC). Additionally, the manufacture cost of the extracts will be estimated using the commercial simulator SuperPro Designer®. (AU)