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1.
J Mol Model ; 30(8): 258, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976085

RESUMEN

CONTEXT: 1,3-Dithiole-2-thione-4,5-dithiolate (dmit) ligands are known for their conductive and optical properties. Dmit compounds have been assessed for use in sensor devices, information storage, spintronics, and optical material applications. Associations with various metallic centers endow dmit complexes with magnetic, optical, conductive, and antioxidant properties. Optical doping can facilitate the fabrication of magnetic conductor materials from ground-state nonmagnetic cations. While most studied complexes involve transition-metal centers due to their diverse chemistry, compounds with representative elements are less explored in the literature. This study investigated the structural and electronic properties of bisdmit complexes with representative Bi(III), Sb(III), and Zn(II) cations. AIMD calculations revealed two new geometries for Bi(III) and Zn(II) complexes, diverging from the isolated geometry typically used in quantum chemical calculations. The coordination of acetonitrile molecules to the cationic centers of the complexes resulted in unstable structures, while the dimerization of the complexes was stable. SA-CASSCF/NEVPT2 calculations were applied to the structures of the isolated complexes and stable dimers, confirming the multireference character of the electronic structure of the three systems and the multiconfigurational character of the Bi(III) complex. The electronic spectra simulated by the STEOM-DLPNO-CCSD calculations accurately reproduced the experimental UV‒Vis spectra indicating the participation of the isolated Bi(III) dmit complex and its dimeric form in solution. METHODOLOGY: AIMD calculations of the dmit salts were conducted using the GFN2-xTB method with 60 explicit acetonitrile molecules as the solvent at 300 K for a total simulation time of 50.0 ps, with printing intervals of 0.5 fs. The final geometries were optimized employing the PBEh-3c compound method, incorporating implicit conductor-like polarizable continuum model (CPCM) solvation for acetonitrile. Local energy decomposition (LED) analysis at the DLPNO-CCSD(T)/Def2-TZVP level of theory was utilized to investigate the stability of the complex geometries identified by AIMD. The electronic structures of the complexes were assessed using the SA-CASSCF/NEVPT2/Def2-TZVP method to confirm the multiconfigurational and multireference nature of their electronic structures. Electronic spectra were analyzed using the STEOM-DLPNO-CCSD/Def2-TZVP method, with CPCM used to simulate an acetonitrile medium.

2.
J Mol Model ; 30(6): 163, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38730058

RESUMEN

CONTEXT: Xanthates are organic compounds of great interest in coordination chemistry due to their different basic sites, which allow them to form complexes with different coordination modes and geometries. These compounds are relevant in the environment and act as heavy metal collectors in aqueous environments. In this theoretical-experimental work, electronic spectroscopy studies of n-propyl xanthate complexes with group 12 metals were performed. This study verified structural differences in these systems, depending on the environment in which they are inserted. In addition, structural differences were observed when the solid was changed to an n-hexane solution. Thus, it was observed that the complexes assume a mononuclear structure in solution, while they present a polymeric form in the solid phase. The electronic spectra obtained through TD-DFT calculations were compared to those of the previously synthesized complexes. In the final theoretical analysis, the main orbitals involved in these transitions were assigned using population analysis calculations. The synthesis of the complexes was confirmed through infrared (MID and FAR), UV‒Vis, Raman, and NMR-1H spectroscopic analyses. METHODS: The structures of the mononuclear and polymeric complexes were optimized in vacuum and n-hexane. Under vacuum, DFT levels M06L/6-311 + + G** + LANL2TZ and M06L/def2-TZVP were used for the mononuclear complexes, and M06L/LANL2DZ + LANL2 were used for the polymer complexes. For the calculations of the mononuclear complexes in n-hexane, the same level of theory was used for the solid state. TD-DFT calculations for 300 excited states were performed with the same levels of theory and used the optimized structures of the complexes. Furthermore, population analysis was carried out on all the systems studied. Gaussian 09 software was used for the structure optimization, TD-DFT, and population analysis calculations. GaussSum software was used to evaluate the molecular orbitals and electronic spectra.

3.
Photochem Photobiol Sci ; 23(2): 271-284, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38305951

RESUMEN

Ultraviolet A (UVA) radiation, present in sunlight, can induce cell redox imbalance leading to cellular damage and even cell death, compromising skin health. Here, we evaluated the in vitro antioxidant and photochemoprotective effect of dithiothreitol (DTT). DTT neutralized the free radicals 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS·+), 2,2-diphenyl-1-picrylhydrazyl (DPPH·), and superoxide anion (O2·-) in in vitro assays, as well as the ferric ion (Fe3+) in the ferric reducing antioxidant power (FRAP) assay. We also evaluated the effect of DTT pre-treatment in L929 dermal fibroblasts and DTT (50 and 100 µM) led to greater cell viability following UVA-irradiation compared to cells that were untreated. Furthermore, the pre-treatment of cells with DTT prevented the increase of intracellular reactive oxygen species (ROS) production, including hydrogen peroxide (H2O2), lipid peroxidation, and DNA condensation, as well as the decrease in mitochondrial membrane potential (Δψm), that occurred following irradiation in untreated cells. The endogenous antioxidant system of cells was also improved in irradiated cells that were DTT pre-treated compared to the untreated cells, as the activity of the superoxide dismutase (SOD) and catalase (CAT) enzymes remained as high as non-irradiated cells, while the activity levels were depleted in the untreated irradiated cells. Furthermore, DTT reduced necrosis in UVA-irradiated fibroblasts. Together, these results showed that DTT may have promising use in the prevention of skin photoaging and photodamage induced by UVA, as it provided photochemoprotection against the harmful effects of this radiation, reducing oxidative stress and cell death, due mainly to its antioxidant capacity.


Asunto(s)
Antioxidantes , Peróxido de Hidrógeno , Humanos , Antioxidantes/farmacología , Antioxidantes/metabolismo , Ditiotreitol/farmacología , Ditiotreitol/metabolismo , Peróxido de Hidrógeno/farmacología , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Piel/efectos de la radiación , Rayos Ultravioleta , Necrosis , Fibroblastos
4.
Braz. j. biol ; 84: e258275, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1364498

RESUMEN

Variety assortment enhancement is a normal task that involves enhancing the assortment's quality and upgrading varieties. The findings of a research of imported grape varieties in the southeast of Kazakhstan, namely in the Almaty region's bottom-mountain zone, are presented in this article. The onset and conclusion of the main phenological phases of a grape plant throughout the vegetative period were directly influenced by the climatic and meteorological conditions of this district. In comparison to the recognized variety Almaty early-maturing, it has been proven that types Priusadebny, Iyulsky, and Kuibyshevsk early-maturing have a high degree of eyes wintering buds and may provide a high-quality crop in this location.


O aprimoramento da variedade é uma tarefa normal que envolve o aprimoramento da qualidade da variedade e o aprimoramento das variedades. As descobertas de uma pesquisa de variedades de uvas importadas no sudeste do Cazaquistão, ou seja, na zona de base da montanha da região de Almaty, são apresentadas neste artigo. O início e a conclusão das principais fases fenológicas de uma videira ao longo do período vegetativo foram diretamente influenciados pelas condições climáticas e meteorológicas deste distrito. Em comparação com a variedade reconhecida Almaty de maturação precoce, foi comprovado que os tipos Priusadebny, Iyulsky e Kuibyshevsk de maturação precoce têm um alto grau de gomos de inverno de olhos e podem fornecer uma safra de alta qualidade neste local.


Asunto(s)
Cambio Climático , Producción de Cultivos , Vitis , Kazajstán
5.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469385

RESUMEN

Abstract Variety assortment enhancement is a normal task that involves enhancing the assortment's quality and upgrading varieties. The findings of a research of imported grape varieties in the southeast of Kazakhstan, namely in the Almaty region's bottom-mountain zone, are presented in this article. The onset and conclusion of the main phenological phases of a grape plant throughout the vegetative period were directly influenced by the climatic and meteorological conditions of this district. In comparison to the recognized variety Almaty early-maturing, it has been proven that types Priusadebny, Iyulsky, and Kuibyshevsk early-maturing have a high degree of eyes wintering buds and may provide a high-quality crop in this location.


Resumo O aprimoramento da variedade é uma tarefa normal que envolve o aprimoramento da qualidade da variedade e o aprimoramento das variedades. As descobertas de uma pesquisa de variedades de uvas importadas no sudeste do Cazaquistão, ou seja, na zona de base da montanha da região de Almaty, são apresentadas neste artigo. O início e a conclusão das principais fases fenológicas de uma videira ao longo do período vegetativo foram diretamente influenciados pelas condições climáticas e meteorológicas deste distrito. Em comparação com a variedade reconhecida Almaty de maturação precoce, foi comprovado que os tipos Priusadebny, Iyulsky e Kuibyshevsk de maturação precoce têm um alto grau de gomos de inverno de olhos e podem fornecer uma safra de alta qualidade neste local.

6.
Rev. argent. microbiol ; Rev. argent. microbiol;55(4): 3-3, Dec. 2023.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1550710

RESUMEN

Abstract The use of lactic acid bacteria (LAB) in foods as biocontrol agents against foodborne pathogens has become increasingly known. Under the premise that controlling the adhesion of microorganisms to food contact surfaces is an essential step for meeting the goals of food processing, the aim of this work was to investigate the inhibitory and anti-biofilm effectiveness of Lactobacillus rhamnosus GG (ATCC 53103) and Lactobacillus casei (ATCC 393) against Escherichia coli O157:H7, Salmonella enterica and Listeria monocytogenes. Lactobacillus strains (108UFCCFU/ml) and pathogens (104UFCCFU/ml) were evaluated to monitor LAB anti-adhesive and antibiofilm effect, in two main scenarios: (i) co-adhesion and (ii) pathogen incorporation to stainless steel surfaces with a protective biofilm of Lactobacillus cells. In (i) the predominant effect was observed in L. rhamnosus against S. enterica and L. monocytogenes, whereas in (ii) both LAB significantly reduced the number of pathogenic adherent cells. The effect of pre-established LAB biofilms was more successful in displacing the three pathogens than when they were evaluated under co-adhesion. These findings show that both LAB can be considered good candidates to prevent or inhibit the adhesion and colonization of L. monocytogenes, S. enterica and E. coli O157:H7 on surfaces and conditions of relevance for juice processing industries, offering alternatives for improving the safety and quality of fruit-based products.


Resumen Existe un creciente interés en el uso de bacterias ácido lácticas (BAL) como agentes de biocontrol frente a patógenos de transmisión alimentaria. Bajo la premisa de que el control de la adhesión de microorganismos a superficies de contacto con alimentos es el paso esencial para evitar su contaminación, el objetivo de este trabajo fue investigar la efectividad inhibitoria y antibiofilm de Lactobacillus rhamnosus GG (ATCC 53103) y Lactobacillus casei (ATCC 393) frente a Escherichia coli O157:H7, Salmonella enterica y Listeria monocytogenes. A fin de cumplir con el objetivo propuesto, las cepas de Lactobacillus (108UFCUFC/ml) y los patógenos (104UFCUFC/ml) se ensayaron en 2 escenarios: (1) coadhesión, y (2) incorporación de los patógenos a las superficies de acero inoxidable con un biofilm preformado de Lactobacillus. En (1), el efecto predominante se observó con L. rhamnosus frente a S. enterica y L. monocytogenes, mientras que en (2), ambas BAL redujeron significativamente el número de células patógenas adheridas. En función de estos resultados, concluimos que el efecto de un biofilm preformado de ambas BAL fue más exitoso en el desplazamiento de los 3 patógenos que en coadhesión. Ambas BAL pueden considerarse buenas candidatas para mitigar la adhesión y colonización de L. monocytogenes, S. enterica y E. coli O157:H7 en superficies en condiciones de relevancia para la industria procesadora de jugos, y, de esta manera, ofrecer alternativas para mejorar la seguridad y calidad de los alimentos a base de frutas.

7.
Int. j. morphol ; 41(6): 1837-1845, dic. 2023. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-1528786

RESUMEN

SUMMARY: The potential anti-inflammatory and antifibrotic activity of polyphenolic extracts of blueberry and grape was evaluated in a mouse model of lung damage induced by subcutaneous administration of bleomycin. The results of testing the polyphenolic extracts on two different systemic administration variants of bleomycin (intraperitoneal and subcutaneous) were compared. It was found that regardless of the method of bleomycin administration, indirect cross-acute and subacute damage to the pulmonary system was observed. Both patterns exhibited the same prevalence and severity. The administration of polyphenolic extracts of blueberry and grape to mice resulted in a significant decrease in theseverity of acute and subacute patterns of lung damage, suggesting their protective properties for the microcirculatory bed and a pronounced anti-inflammatory effect.


La potencial actividad antiinflamatoria y antifibrótica de los extractos polifenólicos de arándano y uva se evaluó en un modelo de daño pulmonar en ratón inducido por la administración subcutánea de bleomicina. Se compararon los resultados de las pruebas de los extractos polifenólicos en dos variantes diferentes de administración sistémica de bleomicina (intraperitoneal y subcutánea). Se encontró que, independientemente del método de administración de bleomicina, se observaba daño indirecto cruzado, agudo y subagudo al sistema pulmonar. Ambos patrones exhibieron la misma prevalencia y gravedad. La administración de extractos polifenólicos de arándano y uva a ratones dio como resultado una disminución significativa en la gravedad de los patrones agudos y subagudos de daño pulmonar, lo que sugiere sus propiedades protectoras del lecho micro- circulatorio y un efecto antiinflamatorio pronunciado.


Asunto(s)
Animales , Ratones , Bleomicina/toxicidad , Extractos Vegetales/administración & dosificación , Lesión Pulmonar/inducido químicamente , Lesión Pulmonar/tratamiento farmacológico , Polifenoles/administración & dosificación , Arándanos Azules (Planta)/química , Vitis/química , Modelos Animales de Enfermedad , Lesión Pulmonar/patología , Pulmón/efectos de los fármacos , Antiinflamatorios/administración & dosificación
8.
Rev. peru. biol. (Impr.) ; 30(4)oct. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1530342

RESUMEN

El Pisco es el destilado del Perú, elaborado a partir de mostos recientemente fermentados con uvas criollas denominadas "pisqueras". Las levaduras son los microorganismos clave en la fermentación y el uso de cepas nativas seleccionadas presenta ventajas competitivas para la tipicidad del producto, así como también para la estandarización del producto y el control microbiológico del proceso. El objetivo fue identificar y seleccionar las cepas de levaduras nativas para la producción del Pisco de uva Quebranta aisladas de procesos productivos de Pisco en el valle de Ica. Para ello, se emplearon técnicas microbiológicas y moleculares mediante el análisis de ITS1-5.8S-ITS2 PCR-RFLP para la identidad taxonómica. La evaluación de las cepas para producir Pisco consistió en el análisis fisicoquímico y organoléptico del destilado obtenido con las cepas seleccionadas. Se evaluaron 3 aislados para la producción de Pisco identificados como Saccharomyces cerevisiae: UNA SC - 25, UNA SC - 49 y UNA SC - 54, de los cuales la cepa UNA SC-49 destacó por mostrar aptitudes enológicas diferentes a las otras cepas. Este trabajo constituye el primer registro de levaduras nativas del Perú para mostos procedentes de uva Quebranta.


El Pisco stands as Peru's distilled spirit, crafted from recently fermented musts derived from native grape varieties known as "pisqueras". Yeasts serve as decisive microorganisms in the fermentation process, and the utilization of selected native strains confers competitive advantages for product typicity, standardization, and microbiological control within the production process. The aim was to identify and select native yeast strains for Quebranta grape Pisco production, isolated from Pisco production processes in the Ica Valley. Microbiological and molecular techniques were employed, utilizing ITS1-5.8S-ITS2 PCR-RFLP analysis for taxonomic identification. The assessment of yeast strains for Pisco production involved the physicochemical and organoleptic analysis of the distilled product obtained using the selected strains. Three isolates were evaluated for Pisco production, identified as Saccharomyces cerevisiae: UNA SC - 25, UNA SC - 49, and UNA SC - 54. Among these, the UNA SC-49 strain stood out due to displaying oenological characteristics distinct from the other strains. This work is the first documentation of native yeasts in Peru for musts derived from Quebranta grapes.

9.
Rev Argent Microbiol ; 55(4): 378-386, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37302907

RESUMEN

The use of lactic acid bacteria (LAB) in foods as biocontrol agents against foodborne pathogens has become increasingly known. Under the premise that controlling the adhesion of microorganisms to food contact surfaces is an essential step for meeting the goals of food processing, the aim of this work was to investigate the inhibitory and anti-biofilm effectiveness of Lactobacillus rhamnosus GG (ATCC 53103) and Lactobacillus casei (ATCC 393) against Escherichia coli O157:H7, Salmonella enterica and Listeria monocytogenes. Lactobacillus strains (108CFU/ml) and pathogens (104CFU/ml) were evaluated to monitor LAB anti-adhesive and antibiofilm effect, in two main scenarios: (i) co-adhesion and (ii) pathogen incorporation to stainless steel surfaces with a protective biofilm of Lactobacillus cells. In (i) the predominant effect was observed in L. rhamnosus against S. enterica and L. monocytogenes, whereas in (ii) both LAB significantly reduced the number of pathogenic adherent cells. The effect of pre-established LAB biofilms was more successful in displacing the three pathogens than when they were evaluated under co-adhesion. These findings show that both LAB can be considered good candidates to prevent or inhibit the adhesion and colonization of L. monocytogenes, S. enterica and E. coli O157:H7 on surfaces and conditions of relevance for juice processing industries, offering alternatives for improving the safety and quality of fruit-based products.


Asunto(s)
Escherichia coli O157 , Lactobacillales , Listeria monocytogenes , Microbiología de Alimentos , Biopelículas , Manipulación de Alimentos
10.
Vitae (Medellín) ; 30(2): 1-7, 2023-05-08. Ilustraciones
Artículo en Inglés | LILACS, COLNAL | ID: biblio-1538037

RESUMEN

Background: The edible green algae Caulerpa racemosa (Forsskal) J. Agardh (Caulerpaceae), also known as "sea grape", is an excellent source of phenolic compounds known for their activity to reduce free radicals. Objectives: The research aims to evaluate the total phenolic content and antioxidant activity of C. racemosa (70% ethanol extracts) obtained from different extraction methods, such as maceration, Soxhlet, and ultrasound. Methods: Total phenolics of the extracts were determined by the colorimetry method using the Folin-Ciocalteu reagent. Total phenol content was expressed as mg gallic acid equivalent (GAE) per g extract. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical was used to assess the antioxidant activity of the extracts. Results: the ethanol extract of C. racemosa obtained from the ultrasonic methods had the highest phenolic content (39.38 mg GAE/g) compared to other extraction methods (Soxhlet was 36.88 mg GAE/g and maceration was 22.05 mg GAE/g). The IC50 value against DPPH of the C. racemosa ethanol extracts using ultrasonic, Soxhlet, and maceration was 352.95, 365.73, and 375.84 µg/mL, respectively. Conclusions: the variation of the extraction methods affected the total phenolics content of C. racemosa ethanol extracts and their antioxidant activity. We reported here the potential of C. racemosa extracts as an antioxidant raw material from marine plants for medicinal, nutraceutical, cosmetics, and food products; however, more research is needed.


Antecedentes: El alga verde comestible Caulerpa racemosa (Forsskal) J. Agardh (Caulerpaceae), también conocida como "uva de mar", es una excelente fuente de compuestos fenólicos conocidos por su actividad para reducir los radicales libres. Objetivos: La investigación pretende evaluar el contenido fenólico total y la actividad antioxidante de C. racemosa (extractos de etanol al 70%) obtenidos a partir de diferentes métodos de extracción, como maceración, Soxhlet y ultrasonido. Métodos: Los fenoles totales de los extractos se determinaron por el método colorimétrico utilizando el reactivo de Folin-Ciocalteu. El contenido total de fenoles se expresó como mg de ácido gálico equivalente (GAE) por g de extracto. Para evaluar la actividad antioxidante de los extractos se utilizó el radical libre 2,2-difenil-1-picrilhidrazilo (DPPH). Resultados: el extracto etanólico de C. racemosa obtenido por ultrasonido presentó el mayor contenido fenólico (39,38 mg GAE/g) en comparación con otros métodos de extracción (Soxhlet fue de 36,88 mg GAE/g y maceración fue de 22,05 mg GAE/g). El valor IC50 frente a DPPH de los extractos etanólicos de C. racemosa mediante ultrasonido, Soxhlet y maceración fue de 352,95, 365,73 y 375,84 µg/mL, respectivamente. Conclusiones: la variación de los métodos de extracción afectó al contenido total de fenoles de los extractos etanólicos de C. racemosa y a su actividad antioxidante. Aquí reportamos el potencial de los extractos de C. racemosa como materia prima antioxidante a partir de plantas marinas para productos medicinales, nutracéuticos, cosméticos y alimenticios; sin embargo, se necesita más investigación.


Asunto(s)
Humanos , Compuestos Fenólicos , Extractos Vegetales , Caulerpa , Antioxidantes
11.
J Photochem Photobiol B ; 242: 112702, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37018912

RESUMEN

The presence of melanopsin (OPN4) has been shown in cultured murine melanocytes and was associated with ultraviolet A radiation (UVA) reception. Here we demonstrated the protective role of OPN4 in skin physiology and the increased UVA-induced damage in its absence. Histological analysis showed a thicker dermis and thinner hypodermal white adipose tissue layer in Opn4-/- (KO) mice than in wild-type (WT) animals. Proteomics analyses revealed molecular signatures associated with proteolysis, remodeling chromatin, DNA damage response (DDR), immune response, and oxidative stress coupled with antioxidant responses in the skin of Opn4 KO mice compared to WT. Skin protein variants were found in Opn4 KO mice and Opn2, Opn3, and Opn5 gene expressions were increased in the genotype. We investigated each genotype response to UVA stimulus (100 kJ/m2). We found an increase of Opn4 gene expression following stimulus on the skin of WT mice suggesting melanopsin as a UVA sensor. Proteomics findings suggest that UVA decreases DDR pathways associated with ROS accumulation and lipid peroxidation in the skin of Opn4 KO mice. Relative changes in methylation (H3-K79) and acetylation sites of histone between genotypes and differentially modulated by UVA stimulus were also observed. We also identified alterations of molecular traits of the central hypothalamus-pituitary- adrenal (HPA) and the skin HPA-like axes in the absence of OPN4. Higher skin corticosterone levels were detected in UVA-stimulated Opn4 KO compared to irradiated WT mice. Taken altogether, functional proteomics associated with gene expression experiments allowed a high-throughput evaluation that suggests an important protective role of OPN4 in regulating skin physiology in the presence and absence of UVA radiation.


Asunto(s)
Opsinas de Bastones , Piel , Animales , Ratones , Homeostasis , Melanocitos/metabolismo , Proteínas de la Membrana/metabolismo , Opsinas de Bastones/genética , Opsinas de Bastones/metabolismo , Piel/metabolismo , Rayos Ultravioleta/efectos adversos
12.
Plants (Basel) ; 12(5)2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36903840

RESUMEN

Overexposure to solar radiation has become an increasingly worrying problem due to the damage to the skin caused by ultraviolet radiation (UVR). In previous studies, the potential of an extract enriched with glycosylated flavonoids from the endemic Colombian high-mountain plant Baccharis antioquensis as a photoprotector and antioxidant was demonstrated. Therefore, in this work we sought to develop a dermocosmetic formulation with broad-spectrum photoprotection from the hydrolysates and purified polyphenols obtained from this species. Hence, the extraction of its polyphenols with different solvents was evaluated, followed by hydrolysis and purification, in addition to the characterization of its main compounds by HPLC-DAD and HPLC-MS, and evaluation of its photoprotective capacity through the measurement of the Sun Protection Factor (SPF), UVA Protection Factor (UVAPF), other Biological Effective Protection Factors (BEPFs), and its safety through the cytotoxicity. In the dry methanolic extract (DME) and purified methanolic extract (PME), flavonoids such as quercetin and kaempferol were found, which demonstrated antiradical capacity, as well as UVA-UVB photoprotection and prevention of harmful biological effects, such as elastosis, photoaging, immunosuppression, DNA damage, among others, which demonstrates the potential of the ingredients in this type of extract to be applied in photoprotection dermocosmetics.

13.
Microbiology (Reading) ; 169(2)2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36757866

RESUMEN

Pseudomonas aeruginosa is a versatile bacterium capable of adapting to a wide range of stress factors, including solar UVA radiation (400-315 nm). High UVA doses produce lethal effects due to the action of reactive oxygen species. Sublethal UVA doses also induces oxidative damage, but, in addition, it triggers a variety of adaptive responses, including the overexpression of pelA and pslA genes in P. aeruginosa. These genes encode the synthesis of Pel and Psl, which are essential polysaccharides in biofilm formation. The present study analysed the role of Pel and Psl in the adaptive responses generated by exposure to low UVA doses, and their importance in the response to lethal doses of UVA, hydrogen peroxide (H2O2), and sodium hypochlorite, in both planktonic cells and submerged and air-liquid interface (ALI) biofilms. It also studied the roles of Pel and Psl in P. aeruginosa-Staphylococcus aureus interaction. The results demonstrate that the capacity of sublethal UVA exposure to increase cell hydrophobicity and cell attachment and generate cross-protection phenomena in P. aeruginosa depends on the presence of Pel and Psl. The study also shows that Pel and Psl have a key role in the tolerance to lethal doses of UVA radiation, sodium hypochlorite and H2O2, in both biofilms and planktonic cells. Finally, co-culture assays showed total inhibition of S. aureus growth in presence of P. aeruginosa. This phenomenon depends, at least in part, on the simultaneous presence of Pel and Psl in planktonic cells and biofilms, suggesting a relevant role of these polysaccharides in the interaction between these species.


Asunto(s)
Peróxido de Hidrógeno , Hipoclorito de Sodio , Peróxido de Hidrógeno/farmacología , Hipoclorito de Sodio/farmacología , Pseudomonas aeruginosa/fisiología , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Polisacáridos Bacterianos/metabolismo , Biopelículas , Estrés Oxidativo
14.
Int. j. morphol ; 41(1): 51-58, feb. 2023. ilus, tab, graf
Artículo en Inglés | LILACS | ID: biblio-1430524

RESUMEN

SUMMARY: An experimental morphological and morphometric study of the antifibrotic function of blueberry and grape extracts was carried out on a model of lung injury in mice induced by intraperitoneal administration of bleomycin. During intraperitoneal administration of bleomycin to mice, acute and subacute damage to the pulmonary system was noted. Both patterns had the same prevalence and severity. The administration of polyphenolic extracts of blueberry and grape to mice showed a significant reduction in the severity of the acute and subacute pattern of lung injury. Blueberry and grape extracts reduce the acute phase of damage to the microvasculature, enhance phagocytic function, have an anti-inflammatory effect, reducing the degree of lymphohistiocytic infiltration and locoregional foci of residual inflammatory effects.


Se realizó un estudio experimental morfológico y morfométrico de la función antifibrótica de extractos de arándano y uva en un modelo de lesión pulmonar en ratones inducida por la administración intraperitoneal de bleomicina. Durante la administración intraperitoneal de bleomicina a ratones, se observaron daños agudos y subagudos en el sistema pulmonar. Ambos patrones tuvieron la misma prevalencia y severidad. La administración de extractos polifenólicos de arándano y uva a ratones mostró una reducción significativa en la severidad del patrón agudo y subagudo de lesión pulmonar. Los extractos de arándano y uva reducen la fase aguda del daño a la microvasculatura, mejoran la función fagocítica, tienen un efecto antiinflamatorio, reducen el grado de infiltración linfohistiocítica y los focos locorregionales de efectos inflamatorios residuales.


Asunto(s)
Animales , Ratones , Fibrosis Pulmonar/tratamiento farmacológico , Bleomicina/toxicidad , Extractos Vegetales/administración & dosificación , Arándanos Azules (Planta)/química , Polifenoles/administración & dosificación , Antifibróticos/administración & dosificación , Fibrosis Pulmonar/inducido químicamente , Modelos Animales de Enfermedad , Antibióticos Antineoplásicos/toxicidad
15.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1421843

RESUMEN

El objetivo del estudio es determinar el efecto de distintas concentraciones de un gel experimental a base de extracto etanólico de semillas de uva (Vitis vinifera L) sobre la resistencia a la adhesión de resina nanohíbrida. Se obtuvo el extracto etanólico a base de Semillas de Uva (EESU) por maceración en alcohol al 70 % durante 45 días. Se reconstituyó el principio activo de las semillas de uva en forma de polvo mezclando 200 ml de agua ultrapura, 2 g. de Carbopol 940, 20 g. de glicerol, 20g. de propilenglicol, 1g. de benzoato de sodio, 1.5 de trietanolamina, obteniendo un gel con un pH de 14, en concentraciones de 5 %, 10 % y 15 %. La sustancia madre fue sometida a cromatografía en capa fina HPLC para identificar sus componentes químicos hallando compuestos fenólicos (ácido Gálico), taninos y en menor cantidad flavonoides. No existieron diferencias significativas entre los grupos control y experimentales cuya tracción se realizó inmediatamente al tratamiento de aclaramiento dental, a los 7 días y 14 días. El extracto etanólico de semillas de uva (Vitis Vinífera L) en concentraciones de 5 %, 10 % y 15 % tuvieron el mismo efecto sobre la resistencia a la adhesión de resina nanohíbrida.


The objective of the study is to determine the effect of different concentrations of an experimental gel based on ethanolic extract of grape seeds (Vitis vinifera L) on the resistance to adhesion of nanohybrid resin The ethanolic extract based on Grape Seeds (EESU) by maceration in 70 % alcohol for 45 days. The active principle of grape seeds was reconstituted in powder form by mixing 200 ml of ultrapure water, 2 g. of Carbopol 940, 20 g. glycerol, 20g. of propylene glycol, 1g. of sodium benzoate, 1.5 of triethanolamine, obtaining a gel with a pH of 14, in concentrations of 5 %, 10 % and 15 %. The base substance was subjected to HPLC thin-layer chromatography to identify its chemical components, finding phenolic compounds (Gallic acid), tannins and, to a lesser extent, flavonoids. There were no significant differences between the control and experimental groups whose traction was performed immediately after dental whitening treatment, at 7 days and 14 days. The ethanolic extract of grape seeds (Vitis vinifera L) in concentrations of 5 %, 10 % and 15 % had the same effect on the resistance to the adhesion of nanohybrid resin.

16.
Arq. ciências saúde UNIPAR ; 26(3): 1091-1098, set-dez. 2022.
Artículo en Portugués | LILACS | ID: biblio-1414403

RESUMEN

Eugenia pyriformis Cambess (Myrtaceae), conhecida popularmente como uvaia. Em seus frutos são encontrados compostos fenólicos com ação antioxidante e nas folhas foram detectados altos teores de flavonoides e taninos hidrolisados que se mostraram inibidor da protease de 2019 - nCoV e SARS-CoV. Neste sentido, o objetivo deste estudo foi a obtenção do extrato bruto das folhas, a análise da composição química e a possibilidade da ação antiviral frente ao SARS COV-2. O extrato bruto (EB) foi obtido a partir das folhas secas de E. pyriformis, pela técnica de maceração dinâmica com esgotamento do solvente (etanol 90º GL) e concentrado em evaporador rotativo. Seis gramas do EB foram fracionados em cromatografia em coluna, e eluído com hexano, diclorometano, acetato de etila e metanol, as frações foram concentradas em um evaporador rotativo (Tecnal TE-210). O EB e as frações foram identificadas por cromatografia líquida de alta eficiência à espectrometria de massas de alta resolução (CLAE-ESI/qTOF). A identificação química do extrato bruto e frações das folhas de E. pyriformis evidenciou a presença de compostos fenólicos destacando os ácidos fenólicos, flavonoides e taninos. De forma complementar, foi realizado um levantamento bibliográfico sobre a provável ação antiviral dos compostos fenólicos e taninos presentes nas folhas de uvaia. Os resultados evidenciaram que os flavonoides quercetina e kaempferol possuem ação antiviral quando se ligam a glicoproteína do envelope ou capsídeo viral interferindo na ligação e penetração do vírus na célula. Este resultado coloca as folhas de E. pyriformis na lista de plantas com ação antiviral.


Eugenia pyriformis Cambess (Myrtaceae), popularly known as uvaia. In its fruits, phenolic compounds with antioxidant action are found and in the leaves, high levels of flavonoids and hydrolyzed tannins were detected, which proved to be an inhibitor of the 2019 protease - nCoV and SARS-CoV. In this sense, the objective of this study was to obtain the crude extract of the leaves, the analysis of the chemical composition and the possibility of antiviral action against SARS COV-2. The crude extract (EB) was obtained from the dried leaves of E. pyriformis, by the dynamic maceration technique with solvent exhaustion (ethanol 90º GL) and concentrated in a rotary evaporator. Six grams of EB were fractionated in column chromatography, and eluted with hexane, dichloromethane, ethyl acetate and methanol, the fractions were concentrated on a rotary evaporator (Tecnal TE-210). EB and fractions were identified by high performance liquid chromatography using high resolution mass spectrometry (HPLC-ESI/qTOF). The chemical identification of the crude extract and fractions of E. pyriformis leaves evidenced the presence of phenolic compounds, highlighting phenolic acids, flavonoids and tannins. In addition, a bibliographic survey was carried out on the probable antiviral action of phenolic compounds and tannins present in uvaia leaves. The results showed that the flavonoids quercetin and kaempferol have antiviral action when they bind to the envelope glycoprotein or viral capsid, interfering with the binding and penetration of the virus into the cell. This result places E. pyriformis leaves in the list of plants with antiviral action.


Eugenia pyriformis Cambess (Myrtaceae), conocida popularmente como uvaia. En sus frutos se encuentran compuestos fenólicos con acción antioxidante y en las hojas se detectaron altos contenidos de flavonoides y taninos hidrolizados que demostraron inhibir la proteasa de 2019 - nCoV y SARS-CoV. En este sentido, el objetivo de este estudio fue obtener el extracto crudo de las hojas, el análisis de la composición química y la posibilidad de acción antiviral contra el SARS COV-2. El extracto crudo (EB) se obtuvo a partir de las hojas secas de E. pyriformis, mediante la técnica de maceración dinámica con agotamiento del disolvente (etanol 90º GL) y se concentró en evaporador rotatorio. Seis gramos de EB se fraccionaron en cromatografía en columna, y se eluyeron con hexano, diclorometano, acetato de etilo y metanol, las fracciones se concentraron en un evaporador rotatorio (Tecnal TE-210). El EB y las fracciones se identificaron mediante cromatografía líquida de alta resolución a espectrometría de masas de alta resolución (HPLC-ESI/qTOF). La identificación química del extracto crudo y de las fracciones de las hojas de E. pyriformis mostró la presencia de compuestos fenólicos destacando los ácidos fenólicos, los flavonoides y los taninos. De forma complementaria, se realizó un estudio bibliográfico sobre la probable acción antiviral de los compuestos fenólicos y los taninos presentes en las hojas de la uva. Los resultados mostraron que los flavonoides quercetina y kaempferol tienen acción antiviral cuando se unen a la glicoproteína de la envoltura o cápside viral, interfiriendo en la unión y penetración del virus en la célula. Este resultado sitúa a las hojas de E. pyriformis en la lista de plantas con acción antiviral.


Asunto(s)
Hojas de la Planta/química , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/química , Eugenia/química , Antivirales/farmacología , Quercetina/farmacología , Flavonoides/farmacología , Cromatografía Líquida de Alta Presión/métodos , Quempferoles/farmacología , Taninos Hidrolizables/farmacología , Compuestos Fenólicos
17.
Photochem Photobiol Sci ; 21(9): 1647-1657, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35666464

RESUMEN

Photoallergy is a photosensitivity disorder associated with a modified ability of the skin to react to the combined effect of drugs and sunlight. It has been attributed to the covalent conjugation of proteins with a photosensitizer, yielding modified macromolecules that can act as antigen provoking the immune system response. The potential role of some endogenous compounds as photoallergens has not been fully established. It has been previously proposed that pterins, which are endogenous photosensitizers present in human skin under pathological conditions, are able to covalently bind to proteins. Here, we evaluated the capability of pterin (Ptr) to form photoadducts with free Lysine (Lys) and poly-L-lysine (poly-Lys). The findings obtained using chromatographic and spectroscopic tools, confirm the formation of photoadducts of Ptr with Lys residues. With poly-Lys the resulting adduct retains the spectroscopic properties of the photosensitizer, suggesting that the aromatic Ptr structure is conserved. On the other hand, the photoproduct formed with free Lys does not behave like Ptr, which suggests that if this product is a photoadduct, a chemical modification may have occurred during the photochemical reaction that alters the pterin moiety.


Asunto(s)
Dermatitis Fotoalérgica , Humanos , Lisina , Fármacos Fotosensibilizantes/farmacología , Pterinas/química , Piel
18.
Photochem Photobiol Sci ; 21(8): 1459-1472, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35551642

RESUMEN

Pseudomonas aeruginosa is an extremely versatile microorganism that survives in a wide variety of niches. It is capable to respond rapidly to changes in the environment by producing secondary metabolites and virulence factors, including alginate. Alginate is an extracellular polysaccharide that protects the bacteria from antibiotics and oxidative agents, and enhances cell adhesion to solid surfaces in the process of biofilm formation. In the present study, we analyzed the role of alginate in the response of P. aeruginosa to lethal doses of ultraviolet-A (UVA) radiation, the major fraction of solar UV radiation reaching the Earth's surface. We also studied the role of alginate in the context of the adaptive responses generated when P. aeruginosa is exposed to sublethal doses of UVA radiation. The survival studies demonstrated that alginate has a key role in the resistance of P. aeruginosa to the oxidative stress generated by lethal UVA doses, both in planktonic cells and in static biofilms. In addition, the presence of alginate proved to be essential in the occurrence of adaptive responses such as induction of biofilm formation and cross-protection against hydrogen peroxide and sodium hypochlorite, both generated by exposure to low UVA doses. Finally, we demonstrated that the increase of biofilm formation is accompanied by an increase in alginate concentration in the biofilm matrix, possibly through the ppGpp-dependent induction of genes related to alginate regulation (algR and algU) and biosynthesis (algD operon). Given the importance of alginate in biofilm formation and its protective roles, better understanding of the mechanisms associated to its functions and synthesis is relevant, given the normal exposure of P. aeruginosa to UVA radiation and other types of oxidative stresses.


Asunto(s)
Plancton , Pseudomonas aeruginosa , Alginatos/metabolismo , Alginatos/farmacología , Biopelículas , Peróxido de Hidrógeno/farmacología , Pseudomonas aeruginosa/fisiología
19.
Photochem Photobiol ; 98(1): 211-219, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34289116

RESUMEN

The photoprotective and antioxidant activities of extracts of six species of plants collected in a high mountain ecosystem at 3150 m.a.s.l. were evaluated. In vitro photoprotection according to UVA-UVB absorption spectrum, Sun Protection Factor (SPF), UVA Protection Factor (UVAPF), (critical wavelength) λc and UVA/UVB Ratio were assessed. Also, the antioxidant activity was determined using the DPPH radical assay and the inhibition of lipid peroxidation in methyl linoleate (MeLo). Total anthocyanins content (TAC) and total polyphenolic content (TPC) were evaluated. Among the extracts evaluated, the extract of B. antioquensis, an endemic plant of Colombia, showed a significant photoprotection against UVA-UVB range, with SPF values of 15 ± 2 and UVAPF of 7 ± 1, λc : 378, UVA/UVB Ratio: 0.78. Furthermore, this extract presented an excellent antioxidant activity, with EC50 of 0.17 ± 0.04 g of dry extract/mmol DPPH, a value of TPC of 464 ± 9 mg gallic acid equivalents (GAE)/g dry extract and significant inhibition of MeLo peroxidation. The results suggest that the extract of B. antioquensis has the best quality to be a source of new UV filters, with a broad spectrum of protection and antioxidant properties.


Asunto(s)
Antioxidantes , Protectores Solares , Antocianinas , Antioxidantes/química , Antioxidantes/farmacología , Ecosistema , Extractos Vegetales/química , Extractos Vegetales/farmacología , Plantas , Protectores Solares/química , Protectores Solares/farmacología , Rayos Ultravioleta
20.
Environ Technol ; 43(2): 286-300, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32559130

RESUMEN

UV/persulfate (UV/PS) technologies have gained increased attention as efficient alternatives for removing pollutants from different classes, although processes based on the UVA-driven S2O82- (PS) activation have not yet been discussed in the literature for the removal of the nonionic surfactant nonylphenol polyethoxylate (NPEO). The present study investigated the simultaneous effect of the initial persulfate concentration ([PS]0) and specific photon emission rate (EP,0) on NPEO degradation by UVA/PS following a Doehlert experimental design. The results for [NPEO]0 = (4.65 ± 0.15) mg L-1 indicated more than 97.8% NPEO removal after 2 h, with pseudo first-order specific degradation rate (kobs) of 0.0320 min-1, for [PS]0 = 7.75 mmol L-1 and EP,0 = 0.437 µmol photons L-1 s-1. Under these conditions, NPEO half-life time was about 22 min, and the EC50-48 h (% v/v) values for Daphnia similis before and after treatment did not differ significantly. Higher values of EP,0 would influence NPEO removal for [PS]0 not higher than 8-10 mmol L-1, although lower degradation efficiencies were obtained with higher [NPEO]0 or real wastewater, except for longer reaction times. Additionally, UVA/PS showed to be efficient for tensoactivity removal, despite the negligible total organic carbon (TOC) removal achieved. Finally, UVC and UVA resulted in NPEO degradation higher than 96% and similar tensoactivity removals when UVA/PS was conducted under optimal conditions ([PS]0 = 10 mmol L-1; EP,0 = 0.324 µmol photons L-1 s-1), suggesting that UVA radiation available in solar light could be advantageously employed for NPEO removal at concentrations usually found in wastewater.


Asunto(s)
Contaminantes Químicos del Agua , Oxidación-Reducción , Fenoles , Aguas Residuales , Contaminantes Químicos del Agua/análisis
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