Actual solubility (S real. ), level of hydrophilic-lipophilic balance (HLBRequ., HLBD, HLBG) and partition coefficient (log P) of phytochemicals contained in Ext. Camellia sinensis L. aqu. siccum in the light of general Hildebrand-Scatchard-Fedors theory

摘要

Introduction: Using the general Hildebrand-Scatchard-Fedors theory of solubility, the mole fraction (x₂) of solubility of phytochemicals contained in the dry green tea leaves was calculated which determines the profile of pharmacological activity. Objective: The applicative purpose of the study was to estimate the actual solubility of phytochemicals – S_|real.| [mol/dm3] in water and in water-ethanol solutions of diversified polarity (ε_M) for their selective extraction and optimal formulation of oral solid dosage form. Methods: The basic physico-chemical and structural quantities of phytochemicals and corresponding mathematical equations of general Hildebrand-Scatchard-Fedors theory of solubility were used to calculate the actual solubility – S_|real.| and the level of hydrophilic-lipophilic balance (HLB). Results: The calculated actual solubility values – S|real.| [mol/dm3] collated with correlation equations enabled the assessment of phytochemical capability for the process of mass exchange on phase boundary. Correlation equations for the dependence log P = f (– log S_|real.|) point to the structural preferences of phytochemicals in the kinetics of the mass exchange (diffusion) through the natural phase boundary. Conclusions: Calculations and correlations between the values characterizing the actual solubility – S_|real.|, media polarity (water, ethanol and their solutions) and the partition coefficient (log P) including the level of hydrophilic-lipophilic balance (HLB) show that basing on thermodynamic components of the general Hildebrand-Scatchard-Fedors theory of solubility, the diffusion profile of phytochemicals contained in the green tea extract ( Ext. Camellia sinensis L. aqu. siccum ) through the biological phase boundary as well as optimal choice of the extraction medium for selective extraction of the class of phytochemicals can be estimated.