RESUMEN
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.
Asunto(s)
Agave , Cosméticos , Residuos Industriales , Agave/química , Antioxidantes/farmacología , Extractos Vegetales , Etanol , AguaRESUMEN
In a recent study, our research group demonstrated that the essential oil of Ocotea odorifera (EOOO) and its major compound safrole potentiated the action fluoroquinolones, modulating bacterial resistance possibly due to direct inhibition of efflux pumps. Thus, in the present study, we investigated whether these treatments could enhance the activity of gentamicin and erythromycin against multidrug-resistant (MDR) bacteria. The EOOO was extracted by hydrodistillation, and the phytochemical analysis was performed by gas chromatography coupled to mass spectrometry (GC-MS). The antibiotic-enhancing effect of the EOOO and safrole against MDR strains of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa was analyzed by the broth microdilution method. The chemical analysis confirmed the presence of safrole as a major component among the 16 compounds identified in the EOOO. Both the essential oil and the isolated compound showed clinically relevant antibacterial activities against S. aureus. Regarding the modulation of antibiotic resistance, the EOOO was found to enhance the activity of erythromycin against the strains of P. aeruginosa and S. aureus, as well as improving the action of gentamicin against S. aureus. On the other hand, safrole potentiated the activity of gentamicin against the S. aureus strain alone. It is concluded, therefore, that the EOOO and safrole can enhance the activity of macrolides and aminoglycosides, and as such are useful in the development of therapeutic tools to combat bacterial resistance against these classes of antibiotics.
Asunto(s)
Ocotea , Aceites Volátiles , Antibacterianos/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/farmacología , Safrol/farmacología , Staphylococcus aureusRESUMEN
The present study evaluated the cytotoxicity, antioxidant potential, and antimicrobial effect on the antibiotic activity modulation of gelatin nanoparticles containing buriti oil (OPG). The cytotoxicity analysis was performed on Chinese Hamster Ovary Cells (CHO) using a MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] test. The antioxidant potential of buriti oil and OPG was determined by total antioxidant capacity, reducing power, and the ABTS (2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid) test. The modulating antimicrobial activity was evaluated by determining the minimum inhibitory concentration (MIC) concentration against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, gentamicin and norflaxacillin. The nanoformulation of OPG did not show a cytotoxic effect on CHO cells and had a higher antioxidant potential than free buriti oil (p<0.05). The combination of antibiotics with free buriti oil and OPG was more efficient in inhibiting E. coli and P. aeruginosa than isolated norfloxacillin and gentamicin (p<0.05). Regarding the inhibition of S. aureus, OPG in combination with norfloxacillin reduced MIC by 50%. Nanoencapsulation was a viable alternative to enhance functionality and adding commercial value to buriti oil.
Asunto(s)
Antioxidantes , Arecaceae , Animales , Antibacterianos/farmacología , Antioxidantes/farmacología , Células CHO , Carotenoides , Cricetinae , Cricetulus , Escherichia coli , Gelatina , Gentamicinas/farmacología , Pruebas de Sensibilidad Microbiana , Aceites de Plantas , Staphylococcus aureus , PorcinosRESUMEN
The purpose of the present study was to evaluate yellow mombin (Spondias mombin L.) juice as a vehicle for the Lactobacillus acidophilus NRRL B-4495 probiotic. The initial pH and fermentation temperature conditions were optimized by central composite rotational design. The beverage was evaluated for its chemical composition, bioactive properties, microbiological stability, survival in simulated gastrointestinal conditions and sensory analysis. The ideal conditions for probiotic juice production were an initial pH of 6.4 and 16 h of fermentation, with maximum viability of 12.9 ± 0.4 Log CFU/mL. The fermented juice showed a total phenolic concentration of 94.90 ± 7.12 GAE/mL and antioxidant activity, as measured by DPPH (0.31 ± 0.00 µmol TE/mL) and ABTS sequestration (2.59 ± 0.30 µmol TE/mL). Antibacterial activity could also be observed against S. aureus, E. coli and K. pneumoniae. The obtained formulation showed good microbiological stability when stored at 4ºC for 28 days. In addition, there was no significant change in viability after exposure to simulated gastrointestinal conditions. The sensory analysis showed that the probiotic beverage was not well accepted. However, the Just-About-Right (JAR) ideal scale test enabled identifying the specific attributes which need to be improved from the tasters' point of view so that it is possible to improve product acceptance.