HPLC method validation for porcine ear permeability study of oxyresveratrol from Artocarpus lakoocha Roxb. heartwood extract

Context: Oxyresveratrol or 2,3,4,5-tetrahydroxystilbene is the major constituent of Artocarpus lakoocha Roxb. (AL), which possesses several pharmacological activities. It also inhibits a key enzyme of melanogenesis, tyrosinase, resulting in skin lightening. Aims: To develop and validate an HPLC method for the analysis of oxyresveratrol in full porcine ear skin permeation study of A. lakoocha heartwood extract. Methods: A reversed-phase HPLC with a gradient system composed of acetonitrile and 0.05% trifluoroacetic acid at a flow rate of 1 mL/min was developed and validated according to the International Council for Harmonization guideline. All chromatograms were monitored at 320 nm. The analyses of oxyresveratrol permeation using side-by-side diffusion cells were conducted. The amounts of the active compounds were analyzed in the donor, receptor of the side-by-side diffusion cells, as well as accumulation in the skin. Results: The yield of plant extract was 14.68%, with the amount of oxyresveratrol at 372 mg/g of the extract. Relative accuracy was between 98.79–105.74% with 1.87–2.83% intraday precision and 2.89-3.80% interday precision. The linearity showed a good correlation at 0.9994. The recovery of the active compound was approximately 88.53 ± 0.71%. Most of the compound was still on the donor side. Conclusions: The result showed sufficient information for the analysis of oxyresveratrol in the skin permeation study. For further experiments, skin permeation enhancers could be incorporated to improve the efflux of oxyresveratrol into the skin.