DP2-DP6-Enriched Maritime Pine Bark Microcapsules Support Keratinocyte Redox Control and a Nutritional Photoprotection Framework

Oral photoprotection depends on repeated delivery of compounds that can influence the skin response to ultraviolet stress. We examined a BCLC maritime pine bark microcapsule enriched in DP2-DP6 oligomeric proanthocyanidins. The reference material contained 62.4% DP2-DP6 within total proanthocyanidins, with low catechin/epicatechin and DP≥10 fractions. In H₂O₂-challenged HaCaT keratinocytes, intracellular ROS fell from the model value of 100% to 78.4%, 68.5% and 60.7% at 25, 50 and 100 μg/mL; cell viability remained above 93%. During simulated digestion, DP2-DP6 retention was 86.8% after the gastric phase and 78.6% after the intestinal phase. Human studies of standardized French maritime pine bark extract include an eight-week trial in which the ultraviolet dose required for one minimal erythema dose increased during supplementation and a randomized double-blind crossover study in outdoor workers reporting protection against seasonal skin darkening and deterioration of hydration/barrier parameters. The formulation and cell data place ingredient stability and keratinocyte redox control alongside established human photobiology endpoints for BCLC-specific evaluation.