Differential Scanning Calorimetry Data and Solubility of Rosmarinic Acid in Different Pure Solvents and in Binary Mixtures (Methyl Acetate + Water) and (Ethyl Acetate + Water) from 293.2 to 313.2 K

Abstract

The thermodynamic melting properties (temperature, enthalpy, and entropy) of rosmarinic acid were experimentally determined via differential scanning calorimetry. The solubility of rosmarinic acid in three solvents (water, methyl acetate, and ethyl acetate), and in their binary mixtures, were determined. The data obtained experimentally were correlated by way of a modified Apelblat model. Through solubility measurements, the activity coefficient was calculated for the process of dissolving the rosmarinic acid in pure solvents and in their mixtures.

Measurement and PC-SAFT Modeling of the Solubility of Gallic Acid in Aqueous Mixtures of Deep Eutectic Solvents

“…Solubility data in water was in agreement with those of three previous studies ,, with deviations below 13.5% at all of the temperatures. Also, our experimental data shows the best agreement with the literature at 313.15 K with deviations below 14% with nine different studies. ,,,− All of the experimental values show that the solubility of gallic acid increases in the liquid phase on increasing the temperature and follows the following order: aqueous DES2 > aqueous DES1 > aqueous ethylene glycol ≈ aqueous DES3 > aqueous glycerol > pure water.…”

“…The solubility of gallic acid was measured in pure water at 293.15, 303.15, and 313.15 K and at 101.3 kPa. These results were compared with literature values, ,,− as shown in Figure a. Also, the percentage deviation (100 × ( S exp – S lit )/ S lit ) for gallic acid solubility was determined for some literature measurements ( S lit ) compared with our experimental results ( S exp ) at the same temperatures as observed in Figure b.…”

“…(a) Solubility of gallic acid in water (wt %) at different temperatures and at 101.3 kPa and (b) percentage deviations (( S exp – S lit )/ S lit ) of experimental data from this work ( S exp ) with the literature ( S lit ). This work, solid black circle; Noubigh et al, ,, open right-pointing triangle; Lu and Lu, open diamond; Mota et al, open inverted triangle; Daneshfar et al, open square; Srinivas et al, dash; Li et al, open hexagon; Vilas-Boas et al, open triangle; Dabir et al, plus; Dali et al, cross; and Aydi et al, asterisk. The continuous line represents the PC-SAFT model with parameters reported in Table .…”

“…The high availability of gallic acid in these matrixes makes it the common reference to quantify their total polyphenol content in terms of a gallic acid equivalent (mg/L GAE) using the Folin−Ciocalteau assay . Since gallic acid is abundant, has a relatively low cost, and is a stable molecule, there are reports of its solubility in water or aqueous mixtures with some organic solvents. − From our knowledge, there are no reports of gallic acid solubility in aqueous DES mixtures along with the potential changes in the crystalline structure after mixing with the liquid phase. However, there has been a recent study reporting the solubility of gallic acid and other polyphenols in a DES based on choline chloride + xylitol …”

Recent Advances in the Analysis of Rosmarinic Acid From Herbs in the Lamiaceae Family

“…30 The compound is more soluble in most organic solvents, but less soluble in water. 31 Aydi et al 32 investigated the solubility and thermodynamic properties of RA in 3 solvents (water, ethyl acetate, and methyl acetate) and in their binary solvent mixtures at different temperatures ranging from 20°C to 40°C. Their results show that the solubility of RA in individual solvent mixtures increases with the increasing temperatures.…”