Studying and Modeling of the Extraction Properties of the Natural Deep Eutectic Solvent and Sorbitol-Based Solvents in Regard to Biologically Active Substances from Glycyrrhizae Roots

The purpose of this work was the studying and modeling of the extraction properties of the sorbitol-based natural deep eutectic solvent (NADES) and sorbitol-based solvents in regard to biologically-active substances (BASs) from Glycyrrhizae roots using theoretical fundamentals based on the laws of statistical physics, thermodynamics, and physical chemistry previously developed by us. In our studies, we used Glycyrrhizae roots, simple maceration, plant raw material:solvent ratio 1:10 w/v, temperature 25 °С, extraction time 24 h; standards of licuroside and glycyram; RP HPLC, differential scanning calorimetry, integral dielectric, impedance and conductivity spectroscopy method of analysis; the following solvents: sorbitol-based NADES sorbitol:malic acid:water (1:1:3 in molar ratio), a modified solvent based on NADES sorbitol:malic acid:water:glycerin (1:1:1:1 in molar ratio) and sorbitol-based solvents sorbitol:ethanol:water at different ratios. It has been found that regression equations for sorbitol-based solvents in coordinates predicted by the theory have a high value of determination coefficient that equals to R²e = 0.993 for glycyram and R²e = 0.976 for licuroside. It has been found that the extraction properties of sorbitol-based NADES with a dielectric constant (ε) equal to 33 ± 2 units are equivalent to those of the sorbitol:ethanol:water solvent with ε = 34 units, and the extraction properties of modified solvent based on NADES with ε = 41 ± 2 units are inferior to those of the sorbitol-ethanol-water solvents with maximum value of BASs yield with the dielectric constant range 40÷50 units. The theoretical fundamentals suggested provide a possibility for an explanation of the mechanism, quantitative description of the extraction properties of the solvent, and target search of the optimal solvent by its dielectric constant.

Psychological Traits of Skin Picking Disorder and Psychogenic Itch

Introduction

Despite the intense discussion of psychiatric comorbidity in psychodermatology, research on psychological components of skin picking and psychogenic itch is limited, especially when it concerns patients’ representation of skin perception and their attitude towards disease.

Objectives

To characterize psychological traits of skin picking and psychogenic itch disorder by comparing aspects of bodily experience.

Aims

To reveal internal relations of different components of bodily experience in skin picking and psychogenic itch.

Methods

Thirty patients with skin picking disorder (L98.1) and 18 patients with psychogenic itch (F45.8) participated in the study. The psychosemantic method “Classification of sensations” was used to assess bodily experience. It includes estimation of 80 descriptors from 6 classes of bodily sensations: skin (ex. “itch”), inner body (ex. “sickness”), receptor (ex. “sticky”), emotional (ex. “anxiety”), dynamics (ex. “exhaustion”) and attitudinal descriptors (ex. “bad”). Cluster and factor analysis were performed.

Results

The most significant aspect of bodily experience in skin picking was its dynamics as a transition from irritation to calmness connected with the sensation of itch opposed to all other sensations (there were opposite signs of factor loadings of these variables and they were included in the factor explaining 45% of total variance). In contrast, in psychogenic itch these relations are diffuse and consist of connections between skin sensations and inner bodily sensations and descriptors of emotions reflecting functional origin of disorder.

Conclusion

Traits of psychological components in skin picking disorder and psychogenic itch should be concerned in the complex (psychiatric, psychological and dermatological) treatment of these disorders.

Disclosure of interest

The authors have not supplied their declaration of competing interest.