Modeling of the overal kinetic extraction from Maytenus aquifolia using compressed CO2

Abstract

-In Brazil, the species Maytenus aquifolia and Maytenus ilicifolia are widely used in popular medicine in the form of teas for stomach and ulcer illness treatment. Despite the great interest in Maytenus aquifolia therapeutic properties and the fact that it is an abundant and native plant growing in Brazil, there is a lack of information in the literature concerning the extraction at high pressures. In this context, this work is focused on the mathematical modelling of the packed-bed extraction of Maytenus aquifolia with compressed CO 2 . Three mathematical models were used to represent the experimental data. The experiments were performed in a laboratory-scale unit, evaluating the effects of temperature (293 to 323 K), pressure (100 to 250 bar), and extraction time on the yield of the extracts. Results show that the extraction temperature and solvent density exerted a pronounced effect on yield. The mathematical model of Sovová was the most suitable to represent the experimental extraction data of M. aquifolia.

Supercritical fluid extraction of bioactive compounds

“…The study of supercritical extraction curves and the knowledge of the effects of the operational variables allow the establishment of the extractor volume and solvent flow rate ( 2). According to several researchers [45][46][47][48], the overall extraction curves (OEC), are clearly divided into three periods (as shown in evaluate the effect of temperature and observed that the extraction of phenols was higher at 10 MPa (403,5 mg GAE/100 g DM) than at 20 MPa (272.4 mg GAE/100 g DM). These results can be partially attributed to the low dispersion coefficient of the modified scCO2 which accounts for the axial and radial diffusion mechanisms and to the high porosity of the extraction bed thus reducing the contact between the solvent and the compounds to be extracted causing a loss of process efficiency.…”

Influence of microwave irradiation on kinetics and thermodynamics of extraction of flavonoids from Phyllanthus emblica

“…It is pertinent to note that the knowledge of the kinetics is essential for the design of extraction systems (Baümler et al, 2014;Honarvar and Sajadian, 2013;Minozzo et al, 2012) In the present work, the influence of temperature (T) and solvent-to-feed ratio (S) on the kinetics and thermodynamics of microwave-assisted extraction of flavonoids from P. emblica is reported. It is pertinent to mention that no prior art on the kinetics and thermodynamics of MAE of flavonoids from P. emblica is available in the literature.…”

Novel Bioactive Extraction and Nano-Encapsulation

“…Overall extraction curve (OEC) is divid into three different time phases of mass transfer, (a) constant extraction rate (CER) and phase is called tCER, wherein the compound is packed inside the solute, therefore lead to convection mass transfer; (b) falling extraction rate (FER) and the phase is called tF wherein convection is combined with diffusion mechanism as the external lipid laye the cell membrane fails to remain intact; (c) diffusion control (DC) and the phase is cal tDC. In tDC, the lipid layer is completely corroded and the diffusion starts inside the pl matrix; hence, maximum extraction is achieved [59][60][61]. Moreover, the evaluation of extraction curve was carried out using spline model, where the extraction takes place fr constant phase of extraction to falling extraction rate and then finally to diffusion rate [ In addition, tCER tFER and tDC (in min) indicate the time span of CER, FER and DC spectively.…”