2 research outputs found
Model Comparison for the Prediction of the Solubility of Green Tea Catechins in Ethanol/Water Mixtures
This article evaluates
some of the most used solubility models
and their applicability to antioxidants, namely, the family of catechins.
From the list of possible catechins, the main four were selected for
this study: epicatechin, epigallocatechin, epicatechin gallate, and
epigallocatechin gallate. Both the enthalpy of fusion and melting
temperature were measured experimentally for these four molecules
and compared with the values obtained using predictive methods. Solubility
measurements for mixtures of water and ethanol were performed with
high-throughput experimentation at temperatures of 293 and 303 K.
The experiments show a strong nonideal behavior in both pure and mixed
solvents. A comparison of different models was performed, identifying
the advantages and disadvantages of each model and their performance
in this particular case. Finally, the NRTL-SAC model was found to
be the most accurate model for predicting solubility, with an RMSE
of 0.550
Mechanism of Isoflavone Adsorption from Okara Extracts onto Food-Grade Resins
Okara
is a byproduct of the soy milk industry containing valuable
phytochemicals, called isoflavones, among other components (i.e.,
proteins, sugars, fibers, etc.). As a waste product, okara is an interesting
source material for obtaining valuable chemicals, and knowledge of
the behavior of such components in their complex matrix is a key step
for design of a purification process. Six commercially available
macroporous polymeric resins are investigated to measure and model
the equilibrium properties of the adsorption of isoflavones, proteins,
and total solids onto these resins. A new model is evaluated in which
adsorption of isoflavones onto a protein layer is proposed describing
the system isoflavonesāresin XAD 4 better than a linear isotherm
model. Parameters for both the linear model and the bilayer model
are regressed and reported with their accuracy and correlated to the
hydrophobicity of each of the isoflavones