Prosopis juliflora as a new cosmetic ingredient: Development and clinical evaluation of a bioactive moisturizing and anti-aging innovative solid core
Agave sisalana; Antioxidant; Cosmetics; Photoprotection
Sisal is the main hard fiber produced in the world. In the chemical composition of Agave sisalana residue, carbohydrates, saponins and phenolic compounds are found. Phenolic compounds are used in the cosmetic industry with photoprotective and antioxidant activities. This work aimed to develop a multifunctional formulation with antioxidant and photoprotective activities from the industrial residue of A. sisalana. An ultrasonic extraction of solid plant material was performed, varying the concentrations of the extracting agent (ethanol/water 50%, 80% and 100%). The extract with the best yield was chemically characterized and evaluated for in vitro antioxidant activity. Ten photoprotective formulations were prepared varying the concentrations of the emulsifiers and the shear time. A. sisalana extract at 1.0% was incorporated into the most stable formulations and their preliminary and accelerated stability was evaluated and investigated for safety. The photoprotective formulations containing or not the extract that were stable after 90 days, had the determination of the Sun Protection Factor in vivo, UVA Protection Factor, critical wavelength, and protection against visible and blue light. Ultrasonic extraction using 50% ethanol/water as extractor vehicle showed the best yield. The extract exhibited a good concentration of phenolic compounds and presented in vitro antioxidant activity in the different stages of the oxidative cascade. Emulsions without and with 1.0% A. sisalana extract remained stable for 90 days, showing desirable rheological behavior for a topical cosmetic. The emulsion containing the extract of A. sisalana was shown to be safe after clinical studies. It was verified that the addition of the extract to the photoprotective formulation statistically increased the SPF when compared to the formulation without the extract with protection against UVA radiation, critical wavelength, absorption of visible and blue light and meeting the requirements of current legislation for sunscreens. In view of the results presented, the solid residue of A. sisalana can be used as an ingredient in photoprotective and antioxidant cosmetic formulations.