In Vitro Evaluation of Nanoemulsion formulations of Orthosispon aristatus (Blume) Miq. and Persea americana Mill. Extracts As AntiUrolithiasis Agents
Abstract
Urolithiasis is a condition characterized by the formation of stones within the urinary tract due to crystal deposition. The prevalence of this disease is relatively high and may lead to serious complications, while available therapeutic options remain largely limited to invasive procedures such as surgery. Orthosiphon aristatus (Blume) Miq and Persea americana Mill. possess antioxidant, diuretic, and antiurolithiasis activities attributed to their active compounds, including sinensetin, rosmarinic acid, and quercetin. Due to the low water solubility and limited bioavailability of these compounds, an oil-in-water dispersion system with nanometer-sized globules is required. Nanoemulsions are nanoscale dispersion systems capable of improving the solubility, stability, and penetration of active compounds, thus potentially enhancing the pharmacological activity of natural extracts. This study aimed to formulate a stable nanoemulsion containing a combination of avocado leaf extract Persea americana Mill. and Orthosiphon aristatus (Blume) Miq., to evaluate its physicochemical characteristics, and to determine the best formulation with in vitro antiurolithiasis activity. Solubility testing was performed by dissolving surfactants, co-surfactants, and solvents at ratios of 1:1, 1:2, and 2:1, mixed with both extracts at ratios of 1:4 and 4:1. A pseudo-ternary phase diagram identified the optimal composition, resulting in the best solvent ratio of 1:1. PSA results indicated that particle size successfully fell within the nanoemulsion range. The zeta potential values were within the moderate to low range, suggesting a tendency toward facile agglomeration. Drug release studies demonstrated faster and greater release of active compounds, following specific kinetic models. This study demonstrates that the combination of Persea americana Mill. and Orthosiphon aristatus (Blume) Miq. exhibits antiurolithiasis effects through nanoemulsion formulation.
