Solubility modelling for phytochemicals of Misai Kucing in different solvents

Abstract

Recently development of computer-aided herbal plant extraction process design has received attention for highly positive future outlook of global herbal industries. Solid-liquid equilibrium (SLE) prediction models comprise a core part of the chemical engineering knowledge base required for the computer- aided process design. In this study, solubility model was developed to predict the solubility of several Orthosiphon stamineus ( Misai Kucing ) phytochemicals (i.e. Sinensetin (SEN), Eupatorin (EUP) and Tet- ramethylscutellarein (TMF)) in seven solvents, in addition to creating physicochemical property database comprising of melting point temperature, fusion enthalpy, and SLE solubility data. Quantitative Structure-Property Relationship (QSPR) model was developed for fusion enthalpy prediction with ab- solute average relative deviation (AARD) of 9.33%. For improvement of KT-NIST-UNIFAC model, new subgroups (i.e. aC e CO (fused), aC e O (fused) and C ] C cyclic e OH) were introduced to better represent the molecular structure of studied fl avonoid compounds, and binary interaction parameters were regressed using compiled SLE solubility data. Regressed KT-NIST-UNIFAC model exhibited better per- formance with AARD of 5.27%. Subsequent simulation study using improved model indicated that acetone was compatible for SEN, EUP, and TMF extraction.