Kinetics of aqueous extraction of phenolic compounds from processed yerba mate leaves

Abstract

In this study, the kinetics of aqueous extraction of phenolic compounds from the yerba mate leaves were analyzed. A temperature range between 40°C and 70°C and a ratio of 25 g of mate leaves in 200 mL of water were used. The extraction kinetic was studied adjustment of the kinetics models of first order, second order kinetic model and the second order diffusive model. The goodness of the fit was controlled by the magnitude of the coefficient of determination (R2), the percentage error (EP %) and the square root of the mean square error (RMSE).The second order kinetic models adequately described the extraction process, achieving the best fit with the second order diffusive model (EP%= 0,81 to 2,9; EP%= 11,24 to 14,99 and 4,72 and 6,92) that provided important information about the initial extraction process and the mechanism that occurs in the final extraction stage. The temperature influenced the kinetic parameters; however, the final equilibrium concentration of phenolic compounds was not affected by it. The results of this study allow us to obtain better overall knowledge of the times and temperatures for improved extraction rates and energy consumption for the industrialization of these compounds.

Green algae Ulva lactuca-derived biochar-sulfur improves the adsorption of methylene blue from water

“…The second-order model demonstrates a firm fit, aligning with the first-order R 2 values, indicating a reasonable model agreement. This finding is consistent with previous research that found the second-order kinetic model suitable for describing adsorption processes, as it provides essential information about the initial extraction process and the mechanism occurring in the final extraction stage 74 . Furthermore, the literature supports the use of second-order kinetics for modeling and predicting the behavior of adsorption systems under various operating conditions, emphasizing this model’s applicability in understanding and optimizing adsorption processes 75 .…”

Ultrasound‐assisted extraction of yerba mate leaves for the development of active additives in sports nutrition products

“…The rapid increase in TPC levels in the initial stage of the US‐assisted extraction may be related to swelling and dilatation of the capillaries of the YM leaves (washout mechanism). Whereas, the second decelerated stage may be attributed to the diffusion of the polyphenol compounds until equilibrium was reached (López et al, 2021). For the control extraction assay (conventional procedure: 5 min; 100°C), the obtained TPC value was higher (6.44 ± .03 g GAE/L), compared to the proposed US‐assisted extraction.…”

“…More recently, López et al (2021) characterized the kinetics of the aqueous extraction of phenolic compounds from YM leaves (25 g leaves: 200 mL water) in a conventional batch operation (40–70°C, .5–60 min). Likewise, they obtained a steep increase in the concentration of polyphenol compounds during the first few minutes of extraction, followed by a slower stage that approached the equilibrium polyphenol compounds concentration (~30 min).…”

“…This model, developed by Linares et al (2010), describes the extraction process using two mechanisms (Equation 7), a first term involving a swelling and washing step and, a second period encompassing a diffusion mechanism (López et al, 2021). This model assumes that internal diffusion governs solute transport from the solid phase to the liquid phase as follows: $$$$ C(t)=\frac{C_{\infty}^wt}{t_{w\left(\frac{1}{2}\right)+t}}+{C}_{\infty}^d\left(1-\exp \left({k}_dt\right)\right) $$$$ where C is the concentration at time t (g/L aqueous extract).…”

“…This model, developed by Linares et al (2010), describes the extraction process using two mechanisms (Equation 7), a first term involving a swelling and washing step and, a second period encompassing a diffusion mechanism (López et al, 2021). This model assumes that internal diffusion governs solute transport from the solid phase to the liquid phase as follows:…”