Rubus caesius leaves and stems in antiaging skin care products: antityrosinase, anticollagenase, antimicrobial activity, and transdermal distribution of main phenolic acids.

CONTEXT: The skin is the largest organ of the body, and its proper care significantly influences the well-being of the entire organism. Therefore, the ingredients of cosmetics and dermocosmetics should inhibit processes leading to inflammation and degradation of skin macromolecules. OBJECTIVE: To select the most promising Rubus caesius L. extract for use in cosmetic and dermocosmetic applications. MATERIALS AND METHODS: Water and ethanol extracts from leaves and stems of Rubus caesius L. (European dewberry, Rosaceae) were tested for their antioxidant properties, protective effects against pathogenic bacterial strains and the influence on tyrosinase and collagenase activity. The most biologically active extracts were selected and analyzed using the HPLC method to estimate the content of major phenolic acids and their ability to penetrate into and through porcine skin from hydrogels. RESULTS: Ethanol extracts from Rubus caesius L. demonstrated significant biological activity, particularly in scavenging the ABTS radical and inhibiting tyrosinase and collagenase activity. Furthermore, ethanol extracts were effective against pathogenic bacteria, but not against commensal skin microbiota. Ethanol extracts from leaves and stems were rich in phenolic acids. The permeation experiment through porcine skin from hydrogels revealed that gallic acid and neochlorogenic acid from ethanol leaves extract exhibited the highest permeation capability. DISCUSSION AND CONCLUSION: The ethanol extract demonstrated substantial activity in protecting the skin against pathogens, oxidative stress, and macromolecular degradation. The presence and transdermal permeability of phenolic acids were also confirmed. These findings highlight the high potential of Rubus caesius leaf ethanol extract for inclusion in cosmetic and dermocosmetic formulations.