Activity and stability studies of verbascoside, a novel antioxidant, in dermo-cosmetic and pharmaceutical topical formulations.

We here report the results of our investigations carried out on Verbascoside, a phenylpropanoid glycoside known for its antioxidant, anti-inflammatory and photoprotective actions. Verbascoside was obtained from Buddleia davidii meristematic cells in turn obtained using a sustainable biotechnology platform which employs an in vitro plant cell culture technology. Verbascoside was firstly investigated to assess the behaviour of the active ingredient in solution or in finished preparations in view of its potential topical use, especially in skin protection. Stability studies were performed by HPLC, and PCL assay was adopted to determine the radical scavenging activity toward superoxide anion. The high hydrophilic character of Verbascoside, resulted somewhat in a limitation of possible applications, inducing to explore the derivatization, to obtain by semi-synthetic derivative VPP, an acyl derivative of Verbascoside, that can increase with its lower hydrophilic profile the range of applications. Completely unattended, the VPP revealed increased antioxidant activity both as active ingredient and in dermocosmetic preparations. Stability studies showed a greater stability of VPP in lipophilic vehicle, whereas the parent Verbascoside resulted more stable in an O/W emulsions. Verbascoside was also stable in suppositories, an interesting pharmaceutical form for possible applications to the inflammation of the intestinal mucosa