Pterodon pubescens oil nanoemulsions: physiochemical and microbiological characterization and in vivo anti-inflammatory efficacy studies

ABSTRACT

Abstract Pterodon pubescens (Benth.) Benth., Fabaceae, fruits have been investigated for their anti-inflammatory and antinociceptive activities, and have demonstrated effectiveness in inflammatory conditions. A physiochemical and microbiological stability study was conducted to investigate two nanoemulsion-based delivery systems of two different hydrophilic surfactants (polyethylene glycol-40H castor oil or polyethylene glycol-40 castor oil). The nanoemulsions, containing P. pubescens oil, lecithin, hydrophilic surfactant and water, were analyzed for droplet size distribution, polydispersity index, pH, consistency index, stability against centrifugal force, and active content/vouacapan derivatives. The physicochemical characteristics were followed for 365 days. The nanoemulsion system was evaluated for anti-inflammatory activity by using with a peritonitis model, immediately after preparation and after 365 days of storage at 25 °C. The stability study demonstrated that proper storage (25 °C) preserved the characteristics of the nanoemulsion containing 7.5% polyethylene glycol-40H castor oil, 5% lecithin, and 5% P. pubescens oil. Further, it ensured a shelf life of 365 days as a phytotherapeutic formulation. In the peritonitis assay induced by carrageenan, nanoemulsion prepared with polyethylene glycol-40H castor oil (125 mg/kg) reduced leukocyte migration, even after 365 days of storage (25 °C), highlighting its potential for the treatment of inflammatory diseases. However, further studies are needed to confirm its clinical effectiveness.