Microencapsulated α-Tocopherol and Moringa Extract for Improved Skin Protection: Insights From Human Skin Assessment...

α-Tocopherol is a potent antioxidant naturally present in human skin, protecting against oxidative damage from UV radiation and pollution. While cosmetic applications may enhance skin protection, its stability and effective delivery remain challenging. Moringa oleifera Lam. (Mo) leaves, rich in α-tocopherol and other bioactives, represent a natural alternative.

To develop and compare microcapsules containing synthetic α-tocopherol (MC α-toc) or a combination of α-tocopherol with Mo extract (MC Mo + α-toc), and to evaluate their encapsulation performance, release profile, and efficacy in cosmetic formulations.

Mo extract was obtained by supercritical CO₂ extraction, yielding 232.5 ± 3.2 mg α-tocopherol·g^-1 extract. Both extracts were microencapsulated by complex coacervation using Arabic gum and gelatine A. Franz cell studies assessed release and absorption compared to free α-tocopherol. Microcapsules were incorporated into a hydrating cream and tested in a 60-day study involving 30 healthy Icelandic volunteers. Skin parameters were evaluated against a commercial product.

Microcapsules showed encapsulation efficiency > 93%, loading capacity ~10%, multinucleated morphology, and an average size of 60 μm. Encapsulation enhanced α-tocopherol absorption, with rates of 6% for MC α-toc and 3% for MC Mo + α-toc after 2 h, versus < 1% for nonencapsulated forms. In vivo, MC α-toc cream reduced skin spots (-25%) and brown spots (-48%), improved firmness (+47%), and increased thickness (+15%). MC Mo + α-toc cream reduced red areas (-11%) and improved transepidermal water loss (-25%).

Microencapsulation improved stability and delivery of α-tocopherol and Mo extract, enhancing cosmetic cream performance. Results were comparable or superior to commercial formulations, highlighting their potential for next-generation skincare products.