Use of sisal industrial waste (Agave sisalana Perrine) in sustainable and multifunctional cosmetic products.

OBJECTIVE: Sisal is a common stiff fibre produced around the world, corresponding to approximately 70% of the commercial production of all fibres of this type. The fibres are extracted from the leaves of Agave sisalana, from which approximately 4% of their weight is obtained, with the remaining 96% considered to be residues from the process of the sisal industry. The objective of this work was to obtain a polyphenol-enriched extract from the A. sisalana residue by ultrasonically assisted extraction, characterize it chemically, evaluate in vitro antioxidant activity, and develop safe and stable photoprotective formulations for future application in cosmetic preparations. METHODS: Ultrasonic extraction of solid plant material was performed using 50% ethanol/water (v/v). The extract was chemically characterized by high-performance liquid chromatography equipment associated with classical molecular networking and evaluated for in vitro antioxidant activity by different methodologies. Ten formulations were prepared, varying the component concentrations and the shear time. The 1.0% sisal extract was incorporated into the most stable formulations, and preliminary and accelerated stability were evaluated. The emulsions were investigated for safety by assessment of primary accumulated dermal irritability and sensitization and a dermatological clinical study of phototoxicity and photosensitization. The photoprotective formulations containing or not containing the extract that were stable after 90 days had their in vivo sun protection factor (SPF), UVA protection factor, critical wavelength, and protection against visible and blue light determined. RESULTS: Ultrasound extraction using 50% ethanol/water (EH 50) as an extractor vehicle showed the best yield. The extract exhibited a concentration of phenolic compounds (77.93 mg of equivalent to the standard gallic acid/g) and showed in vitro antioxidant activity. Emulsions without and with 1.0% sisal extract remained stable and safe. The addition of the extract to the photoprotective formulation statistically increased the SPF when compared to the formulation without the extract and offered protection against UVA radiation, critical wavelengths, and absorption of visible and blue light. CONCLUSION: Based on the findings, the solid residue of A. sisalana may be indicated as a component of photoprotective and antioxidant cosmetic formulations.

OBJECTIF: Le sisal est une fibre rigide courante produite dans le monde entier, correspondant à environ 70 % de la production commerciale de toutes les fibres de ce type. Les fibres sont extraites des feuilles d'Agave sisalana dont environ 4 % du poids est obtenu, les 96 % restants étant considérés comme des résidus du procédé de l'industrie du sisal. L'objectif de ce projet était d'obtenir un extrait du résidu d'A. sisalana enrichi en polyphénols par extraction assistée par ultrasons (EAU), de le caractériser chimiquement, d'évaluer l'activité antioxydante in vitro et de développer des formulations photoprotectrices sûres et stables pour une application future dans des préparations cosmétiques. MÉTHODES: L'extraction ultrasonique de la matière végétale solide a été effectuée avec une solution à 50 % d'éthanol/eau (v/v). L'extrait a été chimiquement caractérisé avec un équipement de chromatographie en phase liquide à haute performance associé à un réseau moléculaire (RM) classique, puis évalué pour l'activité antioxydante in vitro par différentes méthodologies. Dix formulations ont été préparées en variant les concentrations des composants et le temps de cisaillement. L'extrait de sisal à 1,0 % a été incorporé dans les formulations les plus stables et la stabilité préliminaire et accélérée a été évaluée. La sécurité d'emploi des émulsions a été étudiée en évaluant l'irritabilité et la sensibilisation cutanées accumulées primaires et l'étude clinique dermatologique de la phototoxicité et de la photosensibilisation. Le facteur de protection solaire in vivo, le facteur de protection UVA, la longueur d'onde critique et la protection contre la lumière visible et bleue ont été déterminées pour les formulations photoprotectrices contenant ou non l'extrait qui étaient stables après 90 jours. RÉSULTATS: L'extraction par ultrasons utilisant une solution à 50 % d'éthanol/eau (EH 50) comme véhicule d'extraction a menée au meilleur rendement. L'extrait a présenté une concentration de composés phénoliques (77,93 mg d'EAG/g) et une activité antioxydante in vitro. Les émulsions sans et avec 1,0 % d'extrait de sisal sont restées stables et sans danger. L'ajout de l'extrait à la formulation photoprotectrice a statistiquement augmenté le SPF par rapport à la formulation sans extrait et a offert une protection contre les rayonnements UVA, la longueur d'onde critique et l'absorption de la lumière visible et bleue. CONCLUSION: D'après ces résultats, les résidus solides d'A. sisalana peuvent être indiqués comme composant des formulations cosmétiques photoprotectrices et antioxydantes.

Development of O/W emulsions containing Euterpe oleracea extract and evaluation of photoprotective efficacy

Euterpe oleracea Mart. is a palm tree popularly known as açai, which is primarily found in northern Brazil. The açai's fruits contain anthocyanins, a class of polyphenols to which antioxidant properties have been attributed. The aim of this work was to develop O/W sunscreens emulsions containing açai glycolic extract (AGE) and to evaluate both their physical stability and photoprotective efficacy. Emulsions containing AGE and sunscreens were formulated using different types and concentrations of polymeric surfactant (acrylates/C 10-30 alkyl acrylate crosspolymer and sodium polyacrylate). The influence of two rheology modifiers (polyacrylamide (and) C13-14/isoparaffin (and) Laureth-7 and Carbomer) on the stability was also investigated. Physical stability was evaluated by preliminary and accelerated studies. Emulsions with 1.0% sodium polyacrylate were stable and exhibited non-newtonian pseudoplastic behavior and thixotropy. Photoprotective efficacy was evaluated by in vivo Sun Protection Factor (SPF) and determination of Protection Factor of UVA (PF-UVA). When AGE was added to the sunscreen emulsion, no significant increase in the in vivo SPF value was observed. The emulsion containing AGE showed PF-UVA = 14.97, 1.69 of the SPF/PF-UVA ratio and a critical wavelength value of 378 nm, and may therefore be considered a sunscreen with UVA and UVB protection.

Euterpe oleracea Mart. é uma palmeira popularmente conhecida como açaí, encontrada no norte do Brasil. O fruto do açaí apresenta em sua composição antocianinas, uma classe de polifenóis à qual é atribuída propriedade antioxidante. Os objetivos desse trabalho foram desenvolver emulsões fotoprotetoras O/A contendo extrato glicólico de açaí (AGE), avaliar a estabilidade física e avaliar a eficácia fotoprotetora. Emulsões contendo AGE e filtros solares foram formuladas utilizando diferentes tipos e concentrações de tensoativo polimérico (acrilates/C 10-30 alquil acrilato polímero cruzado e polilacrilato sódico). A influência de dois modificadores reológicos (poliacrilamida (e) C13-14/isoparafina (e) Laureth-7 e Carbomer) na estabilidade foi avaliada. A estabilidade física das emulsões foi avaliada por meio de estudos de estabilidade preliminar e acelerada. Emulsões com 1,0% poliacrilato sódico foram estáveis, exibiram comportamento não-newtoniano pseudoplástico e tixotrópico. A eficácia fotoprotetora foi avaliada pelo teste in vivo de Fator de Proteção Solar (FPS) e pela determinação do Fator de Proteção UVA (FP-UVA). Quando adicionado o AGE na emulsão contendo filtros solares, não se observou aumento significativo no valor do FPS. A emulsão contendo o AGE apresentou FP-UVA=14,97, a razão FPS/FP-UVA = 1,69 e o comprimento de onda crítico igual a 378 nm, podendo ser considerado um protetor solar com proteção UVA e UVB.