Abstract
alpha -Mangostin, the extract from pericarp of Garcinia mangostana L. or mangosteen fruit, has been applied in various biomedical products because of its minimal skin irritation, and prominent anti-inflammatory, antimicrobial and immune-modulating activities. Owing to its low water solubility, the particle formulations are necessary for the applications of alpha -mangostin in aqueous media. The particle formulations are usually prepared using surfactants and/or polymers, usually at a larger amount of these auxiliaries than the amount of alpha -mangostin itself. Here, we show the self-assembly of alpha -mangostin molecules into water-dispersible particles without a need of any polymers/surfactants. Investigations on chemical structure, crystallinity and thermal properties of the obtained alpha -mangostin particles, in comparison to the conventional alpha -mangostin crystalline solid, confirm no formation of the new compound during the particle formation and suggest changes in intermolecular interactions among alpha -mangostin molecules and significantly more hydroxyl functionality positioned at the particles' surface. The ability of the water suspension of the alpha -mangostin to inhibit the growth of Propionibacterium acnes, the acne-causing bacteria, is similar to that of the solution of the conventional alpha -mangostin in 5% dimethyl sulfoxide. Moreover, at 12.7 ppm in an aqueous environment of RAW 264.7 cell culture, alpha -mangostin suspension exhibits five times higher anti-inflammatory activity than the conventional alpha -mangostin solution, with the same acceptable cytotoxicity of less than 20% cell death.
