Solubility enhancement of extract of Lagenaria siceraria by development of Phospholipon® 90 H modulated phospholipid complex employing Box-Behnken design.

ABSTRACT

In the past decade, plant sterols gained more attention due to their significant therapeutic activity, but their poor solubility and low bioavailability limited their use. Here, we developed and optimized phospholipon® 90H modulated phospholipid (PmP) complex of ethanolic extract of Lagenaria siceraria (EELs) by solvent evaporation using Box-Behnken Design. The optimized PmP complex was then evaluated physico-chemically and functionally by particle size and zeta potential, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR) and apparent solubility studies. Phospholipon® 90 H (1-Oleoyl-2-palmitoyl-phosphatidylcholine) consists of 85% stearic acid and about 15% palmitic acid., with N,N,N-trimethylethanolammonium cation (choline) as a polar head attached to phosphate group acting as an anion, which forms a weaker intermolecular hydrogen bonding with the third hydroxyl group of isolated sterols. This interaction causes the sterols to get incorporated into the phospholipid at the molecular level. Thereby it leads to the formation of PmP-complex, which enhanced chemical stability with improved solubility. The apparent solubility study demonstrated more than 26-fold increase in aqueous solubility of EELs after forming PmP-complex. This complex with enhanced solubility may be formulated into various pharmaceutical dosage forms, and further pharmacological studies may solve the biopharmaceutical aspects related to therapeutic efficacy.