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1.
Bol. latinoam. Caribe plantas med. aromát ; 23(4): 636-644, jul. 2024. graf, tab
مقالة ي الانجليزية | LILACS | ID: biblio-1538072

الملخص

Thechemical composition, antioxidant and antimicrobial activities of the essential oil from aerial parts (leaves and flowers) of Chuquiraga arcuataHarling grown in the Ecuadorian Andes were studied. One hundred and twenty-six compounds were identified in the essential oil. Monoterpene hydrocarbons (45.8%) and oxygenated monoterpenes (44.1%) had the major percentages. The most abundant compounds were camphor (21.6%), myrcene (19.5%), and 1,8-cineole (13.4%). Antioxidant activity was examined using DPPH, ABTS,and FRAP assays. The essential oil had a moderate scavenging effect and reduction of ferric ion capacity through FRAP assay. Antimicrobial activity of the essential oil was observed against four pathogenic bacteria and a fungus. The essential oil exhibited activity against all microorganism strains under test, particularly against Candida albicansand Staphylococcus aureuswith MICs of 2.43-12.10 µg/mL.


Se estudió la composición química, actividades antioxidantes y antimicrobianas del aceite esencial procedente de las partes aérea (hojas y flores) de Chuquiraga arcuataHarling cultivadas en los Andes ecuatorianos. Se identificaron 126 compuestos en el aceite esencial. Los hidrocarburos monoterpénicos (45,8%) y los monoterpenos oxigenados (44,1%) tuvieron el mayor porcentaje. Los compuestos más abundantes fueron alcanfor (21,6%), mirceno (19,5%) y 1,8-cineol (13,4%). La actividadantioxidante se examinó mediante ensayos DPPH, ABTS y FRAP. El aceite esencial tuvo un efecto eliminador moderado y una reducción de la capacidad de iones férricos mediante el ensayo FRAP. Se observó actividad antimicrobiana del aceite esencial contra cuatro bacterias y un hongo patógenos. El aceite esencial mostró actividad contra todas las cepas de microorganismos bajo prueba, particularmente contra Candida albicansy Staphylococcus aureuscon CMI de 2,43-12,10 µg/mL.


الموضوعات
Oils, Volatile/chemistry , Plant Extracts/chemistry , Asteraceae/chemistry , Anti-Infective Agents/chemistry , Antioxidants/chemistry , Bacteria/drug effects , Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Chromatography, Gas , Plant Leaves/chemistry , Monoterpenes/analysis , Ecuador , Hydrocarbons/analysis , Anti-Infective Agents/pharmacology , Antioxidants/pharmacology
2.
Bol. latinoam. Caribe plantas med. aromát ; 23(4): 523-533, jul. 2024. tab
مقالة ي الانجليزية | LILACS | ID: biblio-1538056

الملخص

Leaves of Croton stipulaceuswere extracted (EHex, ECHCl3and EEtOH extracts) to assesstheir antioxidant potential, anti-inflammatory activity in murine models and acute toxicity. EEtOH showed the highest effect in DPPH (37.80% inhibition), FRAP (1065.00 ± 55.30 µmolFe2+) and total polyphenols (231.24 ± 9.05 meq AG/gM). EHex was the most active, ~ 50% inhibition of TPA-induced ear edema; while EEtOH (dose of 2 mg/ear) showed the highest inhibition in the chronic model (97% inhibition), and inhibited MPO activity (48%). In carrageenan-induced edema, ECHCl3(dose 500 mg/kg) was the most active. None of the extracts showed acute toxicity (LD50) at 2 g/kg (p.o.). This work is the first report that supports the traditional use of C. stipulaceusas an anti-inflammatory.


De las hojas de Croton stipulaceusse obtuvieron diferentes extractos (EHex, ECHCl3y EEtOH) evaluando el potencial antioxidante y la actividad antiinflamatoria en modelos murinos y la toxicidad aguda. El EEtOH mostró mayor efecto en DPPH (37.80% inhibición), FRAP (1065.00 ± 55.30 µmolFe2+) y polifenolestotales (231.24 ± 9.05 meq AG/gM). El EHex fue el más activo, cercano al 50% de inhibición del edema auricular inducido con TPA; mientras que el EEtOH (dosis de 2 mg/oreja) mostró la mayor inhibición en el modelo crónico (97% inhibición), e inhibió la actividad de la MPO (48%). En el edema inducido con carragenina, el ECHCl3(dosis 500 mg/kg) fue el más activo. Ninguno de los extractos mostró una toxicidad aguda (DL50) mayor a 2 g/kg (p.o). Este trabajo es el primer reporte que sustenta el uso tradicional de C. stipulaceuscomo antiinflamatorio.


الموضوعات
Animals , Rats , Plant Extracts/administration & dosage , Croton/chemistry , Inflammation/drug therapy , Anti-Inflammatory Agents/administration & dosage , Antioxidants/administration & dosage , Phenols/analysis , Plant Extracts/chemistry , Plant Leaves , Disease Models, Animal , Anti-Inflammatory Agents/chemistry , Antioxidants/chemistry
3.
Int. j. morphol ; 42(3): 663-672, jun. 2024. ilus, tab
مقالة ي الانجليزية | LILACS | ID: biblio-1564620

الملخص

SUMMARY: Etoposide is an effective antimitotic and antineoplastic agent used to treat various human malignancies. In the present study, Etoposide was injected intraperitoneally into the rats at 1 mg/kg/day for 52 days (52 doses). The control animals received physiological saline (0.5 ml) intraperitoneally daily for 52 doses. The body weight of etoposide-treated rats was significantly reduced compared to control rats. Lipid peroxidation demonstrated an insignificant rise in hepatic tissue, a non-significant decline in renal tissue, and a significant reduction in cardiac tissue. The levels of GSH in hepatic and renal tissue were found to be non-significantly increased but significantly increased in cardiac tissue compared to controls. GR activity was found to be considerably decreased in the treated group. G-S-T levels increased significantly in all treated group. Etoposide injections caused a non-significant change in the GPX level of hepatic tissue, whereas renal and cardiac tissues showed a significant increase. The activity of CAT in hepatic tissue was significantly increased, while CAT activity in renal tissue showed a non-significant decrease, whereas in cardiac tissue, significantly lower levels were observed than in control group. The level of CYTp450 in hepatic and cardiac tissues showed a significant increase; however, renal tissue showed non-significant depletion, whereas CYTb5 in hepatic, renal, and cardiac tissues was significantly lower than controls. The protein content in the hepatic tissue was not significantly increased, whereas the total protein in the renal and cardiac tissues was increased significantly. The research finding is indicative of detoxification activity in the etoposide model.


El etopósido es un agente antimitótico y antineoplásico eficaz que se utiliza para tratar diversas neoplasias malignas humanas. En el presente estudio, se inyectó etopósido por vía intraperitoneal a las ratas a razón de 1 mg/kg/día durante 52 días (52 dosis). Los animales control recibieron solución salina fisiológica (0,5 ml) por vía intraperitoneal diariamente por 52 dosis. El peso corporal de las ratas tratadas con etopósido se redujo significativamente en comparación con las ratas del grupo control. La peroxidación lipídica demostró un aumento insignificante del tejido hepático, una disminución no significativa del tejido renal y una reducción significativa del tejido cardíaco. Se encontró que los niveles de GSH en el tejido hepático y renal no aumentaron significativamente, pero sí aumentaron significativamente en el tejido cardíaco en comparación con los controles. Se encontró que la actividad de GR disminuyó considerablemente en el grupo tratado. Los niveles de G-S-T aumentaron significativamente en todos los grupos tratados. Las inyecciones de etopósido provocaron un cambio no significativo en el nivel de GPX del tejido hepático, mientras que los tejidos renal y cardíaco mostraron un aumento significativo. La actividad de CAT en el tejido hepático aumentó significativamente, mientras que la actividad de CAT en el tejido renal mostró una disminución no significativa, mientras que en el tejido cardíaco se observaron niveles significativamente más bajos que en el grupo de control. El nivel de CYTp450 en los tejidos hepático y cardíaco mostró un aumento significativo; sin embargo, el tejido renal mostró un agotamiento no significativo, mientras que CYTb5 en los tejidos hepático, renal y cardíaco fue significativamente menor que los controles. El contenido de proteínas en el tejido hepático no aumentó significativamente, mientras que la proteína total en los tejidos renal y cardíaco aumentó significativamente. El hallazgo de la investigación es indicativo de la actividad de desintoxicación en el modelo de etopósido.


الموضوعات
Animals , Male , Rats , Etoposide/administration & dosage , Heart/drug effects , Kidney/drug effects , Liver/drug effects , Antioxidants/administration & dosage , Organ Size/drug effects , Body Weight/drug effects , Lipid Peroxidation , Cytochromes b5/analysis , Rats, Wistar , Cytochrome P-450 Enzyme System/analysis , Etoposide/pharmacology , Kidney/ultrastructure , Liver/ultrastructure , Microscopy , Myocardium/ultrastructure , Antineoplastic Agents, Phytogenic , Antioxidants/pharmacology
4.
Int. j. morphol ; 42(2): 362-367, abr. 2024. ilus, tab
مقالة ي الانجليزية | LILACS | ID: biblio-1558145

الملخص

SUMMARY: This study evaluated the phytochemical screening, antioxidant capacity, and in vitro anticancer activities of four plants namely, Gypsophila capillaris, Anabasis lachnantha, Haloxylon salicornicum, and Horwoodia dicksoniae which belong to four different families: Caryophyllaceae, Amaranthaceae, Chenopodiaceae, Brassicaceae, respectively. The total phenolics, anthocyanins, saponins, total antioxidant capacity (TAC), and DPPH assays were determined by spectrophotometer. In vitro anticancer activity was assessed using two human cancer cell lines; hepatocellular carcinoma (HepG-2) and breast adenocarcinoma (MCF-7) to estimate the inhibition concentration 50 % (IC50). The results showed that H. dicksoniae has the highest concentrations of phenolics and saponins, while H. salicornicum has the highest DPPH. The highest concentration of TAC was found in G. capillaries. Among the tested extracts, G. capillaries and H. salicornicum have the potential activity against MCF-7 and HepG-2 cell lines in vitro. The content of polyphenols in G. capillaries was profiled by high-performance liquid chromatography (HPLC). The highest concentration among the phenolic compounds was chlorogenic (60.8 µg/ml) while the highest concentration among the flavonoid compounds was hesperidin (1444.92 µg/ml). In summary, G. capillaries and H. salicornicum extracts have potent anticancer activity against HepG-2 and MCF-7 cell lines.


Este estudio evaluó la detección fitoquímica, la capacidad antioxidante y las actividades anticancerígenas in vitro de cuatro plantas, Gypsophila capillaris, Anabasis lachnantha, Haloxylon salicornicum y Horwoodia dicksoniae, que pertenecen a cuatro familias diferentes: Caryophyllaceae, Amaranthaceae, Chenopodiaceae y Brassicaceae, respectivamente. Los ensayos de fenólicos totales, antocianinas, saponinas, capacidad antioxidante total (TAC) y DPPH se determinaron mediante espectrofotómetro. La actividad anticancerígena in vitro se evaluó utilizando dos líneas celulares de cáncer humano; carcinoma hepatocelular (HepG-2) y adenocarcinoma de mama (MCF- 7) para estimar la concentración de inhibición del 50 % (IC50). Los resultados indicaron que H. dicksoniae tiene las concentraciones más altas de fenólicos y saponinas, mientras que H. salicornicum tiene el DPPH más alto. La mayor concentración de TAC se encontró en G. capillaries. Entre los extractos probados, G. capillaries y H. salicornicum tienen actividad potencial contra líneas celulares MCF-7 y HepG-2 in vitro. El contenido de polifenoles en G. capillaries se perfiló mediante cromatografía líquida de alta resolución (HPLC). La concentración más alta entre los compuestos fenólicos fue clorogénica (60,8 µg/ml), mientras que la concentración más alta entre los compuestos flavonoides fue la hesperidina (1444,92 µg/ml). En resumen, los extractos de Gypsophila capillaris y H. salicornicum tienen una potente actividad anticancerígena contra las líneas celulares HepG-2 y MCF-7.


الموضوعات
Humans , Plants, Medicinal/chemistry , Antineoplastic Agents/chemistry , Antioxidants/chemistry , Phenols/analysis , Saponins/analysis , Saudi Arabia , In Vitro Techniques , Chromatography, High Pressure Liquid , Metabolomics , Hep G2 Cells/drug effects , MCF-7 Cells/drug effects , Phytochemicals , Anthocyanins/analysis , Antineoplastic Agents/pharmacology , Antioxidants/pharmacology
5.
Bol. latinoam. Caribe plantas med. aromát ; 23(2): 326-335, mar. 2024. graf, tab
مقالة ي الانجليزية | LILACS | ID: biblio-1552609

الملخص

Morocco has varied wealth of aromatic and medicinal plants (AMPs) which are commonly used for prevention and treatment of vario us diseases or as complementary therapy such for cancer diseases. An ethnobotanical study was carried out in the province of Nador, located northeast of Morocco. A total of 418 persons were interviewed, information about their profile, type of medicinal pl ants existing in this area, plant characteristics and uses of those existing plants. Results showed 35 species distributed in 23 families, the most represented were Lamiaceae (7), Apiaceae (5) and Fabaceae (3). This study revealed that the population mainl y used seeds (28%), leaves (26%), aerial parts (20%) and fruits (14%). Moreover, it has shown that Nerium oleander were used by the local population for cancer treatments. Biological activity of N. oleander showed an antimicrobial effect on Escherichia col i , Pseudomonas aeruginosa and Staphylococcus aureus


Marruecos tiene una riqueza vegetal muy variada de plantas aromáticas y medicinales (AMP) y se utilizan com únmente para la prevención y el tratamiento de diversas enfermedades o como terapia complementaria, como las enfermedades del cáncer. Se llevó a cabo un estudio etnobotánico en la provincia de Nador, situada al noreste de Marruecos. Se entrevistó a un tota l de 418 personas, información sobre su perfil, tipo de plantas medicinales existentes en esta zona, características de las plantas, usos de las plantas existentes, etc. Los resultados mostraron una alta riqueza de especies de 35 especies distribuidas en 2 3 familias, las más representadas fueron Lamiaceae (7), Apiaceae (5) y Fabaceae (3). Este estudio reveló que la población utilizó preferentemente semillas (28%), hojas (26%), partes aéreas (20%) y frutos (14%). Además, se ha demostrado que la población loc al utilizaba Nerium oleander para tratamientos contra el cáncer. La actividad biológica de N. oleander mostró un efecto antimicrobiano sobre Escherichia coli , Pseudomonas aeruginosa y Staphylococcus aureus


الموضوعات
Plants, Medicinal/chemistry , Ethnobotany , Neoplasms/drug therapy , Medicine, Traditional/methods , Morocco , Neoplasms/prevention & control
6.
Rev. chil. nutr ; 51(1)feb. 2024.
مقالة ي الانجليزية | LILACS-Express | LILACS | ID: biblio-1550798

الملخص

The consumption of vegetable oils is common in our daily diet. Rapeseed oil (canola oil) is the third most consumed edible oil in the world, followed by palm and soybean oils in terms of production. Rapeseed oil has a low proportion of saturated fatty acids, while it is rich in unsaturated fatty acids, as well as in healthy compounds such as phenols, tocopherols, phytosterols, carotenoids, and fat-soluble vitamins. However, processing technologies affect the content and functional activities of bioactive compounds in the oil. Aim: To assess any potential effect of hot or cold pressing and a refining process on the nutritional value and the profile of several bioactive compounds in canola oils produced in Chile. Methods: Canola oils were characterized regarding their fatty acid profile, phytosterol and tocopherol composition, total phenol content, and antioxidant activity, according to the mode of extraction (cold or hot pressed) and before and after bWeing subjected to a refining process. Results: Fatty acid profiles were not significantly different in any of the analyzed canola oils. Refining but not temperature extraction led to a sharp decrease of phytosterols and tocopherols. Hot pressing significantly increased the amount of total phenols (3.1 times) and the antioxidant activity measured by ORAC (3.1 times) and DPPH (8.3 times) compared to the cold extraction. However, phenolic concentration and antioxidant capacity decreased after refining. Conclusions: Refining processes should be adjusted to reduce the loss of bioactive compounds in the oil.


El consumo de aceites vegetales es habitual en nuestra dieta diaria. El aceite de colza (aceite de canola) es el tercer aceite comestible más consumido en el mundo, seguido por los aceites de palma y soja en términos de producción. El aceite de colza tiene una baja proporción de ácidos grasos saturados, mientras que es rico en ácidos grasos insaturados, así como en compuestos liposolubles saludables como fenoles, tocoferoles, fitoesteroles, carotenoides y vitaminas. Sin embargo, las tecnologías de procesamiento afectan el contenido y las actividades funcionales de los compuestos bioactivos en el aceite. Objetivo: Evaluar cualquier efecto potencial del prensado en caliente o en frío y un proceso de refinación sobre el valor nutricional y el perfil de varios compuestos bioactivos en los aceites de canola producidos en Chile. Métodos: Los aceites de canola se caracterizaron en cuanto a su perfil de ácidos grasos, composición de fitoesteroles y tocoferoles, contenido de fenoles totales y actividad antioxidante, según el modo de extracción (prensado en frío o en caliente) y antes y después de ser sometidos a un proceso de refinación. Resultados: Los perfiles de ácidos grasos no fueron significativamente diferentes en ninguno de los aceites de canola analizados. La refinación, pero no la extracción en caliente, condujo a una fuerte disminución de los fitoesteroles y tocoferoles. El prensado en caliente aumentó significativamente la cantidad de fenoles totales (3,1 veces) y la actividad antioxidante medida por ORAC (3,1 veces) y DPPH (8,3 veces) en comparación con la extracción en frío. Sin embargo, la concentración de fenoles y la capacidad antioxidante disminuyeron después del refinado. Conclusión: Los procesos de refinación deben ajustarse para reducir la pérdida de compuestos bioactivos en el aceite.

7.
Rev. Baiana Saúde Pública (Online) ; 47(4): 238-254, 20240131.
مقالة ي الانجليزية | LILACS-Express | LILACS | ID: biblio-1537823

الملخص

Species of Pithecellobium (Fabaceae) are used in traditional medicine to treat diabetes, cough, bronchitis, and inflammation. This study aims to evaluate the content and determine the antioxidant activity, phenolic compounds content, and cytotoxicity of the extract and the fractions of Pithecellobium diversifolium. This is unprecedented research with an exotic species from the Caatinga, northeastern Brazil, using High-performance Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (HPLC-ESI-MS). The MeOH fractions of leaves and stem barks showed a high content of flavonoids (198.1 ± 106.50 and 542.7 ± 2.52 mg EqQ/g). The CH2Cl2 fraction of peels showed a high content of total phenolic compounds (516.7 ± 3.00 mg EqAG /g). The DPPH test showed that the CH2Cl2 fraction (leaves) held an EC50 of 0.08 ± 0.02, a higher value than that observed for the standards used in the test­Butylated hydroxyanisole (BHA), Butylated hydroxytoluene (BHT), and ascorbic acid. The AcOEt and MeOH fractions of peels presented moderate cytotoxicity with values below 500 µg/mL. The MeOH fraction of leaves showed seven major compounds: myricetin, quercetin, quercetin-arabinofuranoside, apigenin-triglycosides, and apigenin-diglucoside, being the last three unpublished in studies involving the genus. The tests conducted in this study show the potential of P. diversifolium as a promising source of biomolecules with therapeutic applicability.


Espécies de Pithecellobium (Fabaceae) são usadas na medicina tradicional para tratar diabetes, tosse, bronquite e inflamação. Este estudo teve como objetivo avaliar o teor e determinar a atividade antioxidante, o teor de compostos fenólicos e a citotoxicidade do extrato e das frações de Pithecellobium diversifolium, uma pesquisa inédita com uma espécie exótica da Caatinga do Nordeste do Brasil, utilizando a instrumentação Clae-IES. As frações MeOH das folhas e cascas do caule apresentaram alto teor de flavonoides (198,1 ± 106,50 e 542,7 ± 2,52 mg EqQ/g). A fração CH2Cl2 das cascas apresentou um elevado teor de compostos fenólicos totais (516,7 ± 3,00 mg EqAG/g). O teste DPPH mostrou que a fração CH2Cl2 (folhas) apresentou um EC50 de 0,08 ± 0,02, valor superior ao observado para os padrões utilizados no teste ­ Butil hidroxianisol (BHA), Butil hidroxitolueno (BHT) e ácido ascórbico. As frações AcOEt e MeOH das cascas apresentaram citotoxicidade moderada com valores inferiores a 500 µg/mL. A fração MeOH das folhas apresentou sete compostos majoritários: miricetina, quercetina, quercetina-arabinofuranosídeo, apigenina-triglicosídeos e apigenina-diglucosídeo, sendo os três últimos inéditos em estudos envolvendo o gênero. Os testes realizados demonstram o potencial de P. diversifolium, uma promissora fonte de biomoléculas com aplicabilidade terapêutica.


Las especies de Pithecellobium (Fabaceae) se utilizan en la medicina tradicional para tratar diabetes, tos, bronquitis e inflamación. Este estudio tuvo como objetivo evaluar el contenido y determinar la actividad antioxidante, el contenido de compuestos fenólicos y la citotoxicidad del extracto y de las fracciones de Pithecellobium diversifolium, un estudio inédito con una especie exótica de la Caatinga de la región Nordeste de Brasil, que utilizó la instrumentación HPLC-ESI. Las fracciones MeOH de hojas y cortezas de tallo mostraron un alto contenido de flavonoides (198,1 ± 106,50 y 542,7 ± 2,52 mg EqQ/g). La fracción CH2Cl2 de las cortezas presentó un alto contenido de compuestos fenólicos totales (516,7 ± 3,00 mg EqAG/g). El ensayo DPPH mostró que la fracción CH2Cl2 (hojas) tenía EC50 de 0,08 ± 0,02, valor superior a lo observado para los estándares utilizados en el ensayo ­Butilhidroxianisol (BHA), butilhidroxitolueno (BHT) y ácido ascórbico. Las fracciones AcOEt y MeOH de las cortezas presentaron una citotoxicidad moderada con valores inferiores a 500 µ g/mL. La fracción MeOH de las hojas contiene siete compuestos principales: miricetina, quercetina, quercetina-arabinofuranosido, apigenina-triglucósidos y apigenina-diglucósido, de los cuales los tres últimos son inéditos en estudios sobre el género. Las pruebas realizadas demuestran el potencial de P. diversifolium, una fuente prometedora de biomoléculas con aplicabilidad terapéutica.

8.
Bol. latinoam. Caribe plantas med. aromát ; 23(1): 61-74, ene. 2024. tab
مقالة ي الانجليزية | LILACS | ID: biblio-1552900

الملخص

Although numerous studies have demonstrated the biomedical potential of Myrtus communis L., (Myrtaceae) data on myrt le from Montenegro are scarce. T o evaluate antioxidant, antimutagenic and antibacterial activity of myrtle methanolic extracts. Antioxidant activity was evaluated by measuring free radicals scavenging activity, reducing power and enzyme inhibition. The strongest scavenging activity was towards DPPH radical ( 2,2 - diphenyl - 1 - picry lhydrazyl) (IC 50 1.69 - 2.25 mg/mL) and superoxide anion (IC 50 0.56 to 0.88 mg/mL), followed by high reducing power (428 - 472 mgAA/g.DE) and inhibition of XOD (IC 50 0.308 - 0.6261mg/mL). Antimutagenic activity was evaluated in reverse mutation assays with Esche richia coli WP2 oxyR mutant IC202 and deficient in the induction of antioxidant enzymes. The myrtle extracts strongly inhibited mutagenesis induced by t - BOOH, reaching 70% at the highest concentration applied. Antimicrobial activity was examined on eight different bacterial strains. Gram - positive bacteria, S. epidermis , S. aureus and M. flavus demonstrated the highest sensitivity towards extracts (MICs 4.5 - 9 mg/mL), but significantly lower towards essential oil (MIC 0.42 - 3.32 mg/mL).


Aunque numerosos estudios han demostrado el potencial biomédico de Myrtus communis L., (Myrtaceae), los datos sobre el mirto de Montenegro son escasos. E valuar la actividad antioxidante, antimutagéni ca y antibacteriana de extractos metanólicos de mirto. La actividad antioxidante se evaluó midiendo la actividad de eliminación de radicales libres, el poder reductor y la inhibición enzimática. La actividad secuestrante más fuerte fue hacia DPPH radical ( IC 50 1.69 - 2.25 mg/mL) y radicales de anión superóxido (IC 50 0.56 a 0.88 mg/mL), seguido de alto poder reductor (428 - 472 m gAA/g.DE) e inhibición de XOD (I C 50 0,308 - 0,6261 mg/m L ). La actividad antimutagénica se evaluó en ensayos de mutación inversa con Esche richia coli WP2 oxyR mutante IC202 y deficiente en la inducción de enzimas antioxidantes. Los extractos de mirto inhibieron fuertemente la mutagénesis inducida por t - BOOH, alcanzando el 70% a la mayor concentración aplicada. La actividad antimicrobiana se examinó en octo cepas bacterianas diferentes. Las bacterias grampositivas, S. epidermis , S. aureus y M. flavus demostraron la sensibilidad más alta hacia los extractos (MIC 4.5 - 9 mg/mL), pero significativamente más baja hacia el aceite esencial (MIC 0.42 - 3 .32 mg/mL). Los resultados muestran la gran perspectiva nutrafarmacéutica de la especie montenegrina Myrtus communis .


الموضوعات
Plant Extracts/pharmacology , Myrtus/chemistry , Anti-Infective Agents , Anti-Inflammatory Agents , Antioxidants/therapeutic use , Antioxidants/pharmacology
9.
Tianjin Medical Journal ; (12): 278-284, 2024.
مقالة ي صينى | WPRIM | ID: wpr-1021010

الملخص

Objective To explore the mechanism of Wumei pill on ulcerative colitis(UC)in mice based on the anti oxidative stress pathway of nuclear factor erythroid 2-related factor 2(Nrf2)/antioxidant response element(ARE).Methods Seventy SPF male C57BL/6 mice were randomly divided into the control group,the UC group,the mesalazine group(MES group,0.82 g/kg MES),the low dose Wumei pill group(WMW-L group,5 g/kg crude drug),the middle dose Wumei pill group(WMW-M group,10 g/kg crude drug),the high dose Wumei pill group(WMW-H group,20 g/kg crude drug)and the high dose Wumei pills+Nrf2 inhibitor ML-385 group(WMW-H+ML-385 group,Wumei pills crude drug 20 g/kg+20 mg/kg ML-385),with 10 rats in each group.The disease activity index(DAI)score and colonic mucosa injury score were performed in mice after the last administration.Pathological changes of colonic mucosa in mice were observed by HE staining.The levels of interleukin(IL)-1β,tumor necrosis factor-α(TNF-α)and IL-6 in serum and colon tissue of mice were measured by enzyme-linked immunosorbent assay(ELISA).The content of malondialdehyde(MDA)in serum and colon tissue of mice was determined by thiobarbituric acid colorimetry(TBA).The activity of superoxide dismutase(SOD)in serum and colon tissue of mice was measured by xanthine oxidase method.The activity of glutathione peroxidase(GSH-px)in serum and colon tissue of mice was determined by direct method with dithiodinitrobenzoic acid(DTNB).The positive expression of Nrf2 in colon tissue of mice was observed by immunohistochemistry.The expression of heme oxygenase-1(HO-1)and NAD(P)H:quinone oxidoreductase-1(NQO1)proteins in colon tissue of mice were detected by Western blot assay.Results Compared with the control group,the DAI score,colonic mucosa injury score,colonic histopathology score,levels of IL-1β,TNF-α,IL-6 and MDA in serum and colonic tissue,and expression levels of Nrf2,HO-1 and NQO1 protein in colonic tissue of mice were increased in the UC group,levels of SOD and GSH-px in serum and colon tissue decreased(P<0.05),the colon mucosa of mice was seriously damaged.Compared with the UC group,changes of corresponding indexes were contrary to the above in the MES group,the WMW-M group and the WMW-H group.However,the expression levels of Nrf2,HO-1 and NQO1 proteins in colon tissue were increased(P<0.05),and the damage of colon mucosa in mice was alleviated.Changes of the above indexes were dose-dependent in the WMW-L group,the WMW-M group and the WMW-H group.There were no significant differences in the above indexes between the WMW-H group and the MES group.ML-385 attenuated the improvement effect of high dose Wumei pill on colon mucosa injury.Conclusion Wumei pill may alleviate the colon mucosal damage of UC mice by activating Nrf2/ARE antioxidant stress pathway.

10.
مقالة ي صينى | WPRIM | ID: wpr-1016473

الملخص

ObjectiveThe correlation of Pueraria lobata producing areas, climate factors, total flavonoids of P. lobata, polysaccharide content of P. lobata, and antioxidant activity of P.lobata for medicinal application was analyzed, and the relationship between climate factors and the formation of P. lobata quality was evaluated. MethodThe scavenging rates of 1,1-diphenyl-2-picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl(DPPH) and 2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS) radicals by total flavonoids and polysaccharides of P. lobata were detected, and the correlation between the contents of each component and the information of producing areas and climate factors was analyzed. ResultThe ABTS+ scavenging rate by total flavonoids of P.lobata was negatively correlated with altitude (P<0.05) and positively correlated with annual sunshine hours (P<0.05). The altitude was positively correlated with the total flavonoid content, while the annual sunshine hours were negatively correlated with the total flavonoid content. There was a negative correlation between total flavonoid content and ABTS+ scavenging rate by total flavonoids. In other words, lower altitude and longer annual sunshine hours indicated lower total flavonoid content and higher ABTS+ scavenging rate by total flavonoids. The ABTS+ scavenging rate by polysaccharides of P. lobata was negatively correlated with the frost-free period (P<0.05) and the mean temperature in July (P<0.01). There was a positive correlation between the polysaccharide content of P. lobata and the frost-free period. The mean temperature in July was positively correlated with the polysaccharide content of P. lobata (P<0.05). The polysaccharide content of P. lobata was negatively correlated with the ABTS+ scavenging rate by polysaccharides of P. lobata. In other words, a shorter frost-free period in the producing area and lower mean temperature in July indicated lower polysaccharide content of P. lobata and higher ABTS+ scavenging rate by polysaccharides of P. lobata. The mean temperature in July was significantly correlated with the contents of total flavonoids and polysaccharides in P. lobata samples (P<0.05). The lower mean temperature in July was often accompanied by lower total flavonoid content of P. lobata, lower polysaccharide content of Pueraria lobata, and stronger antioxidant activity of P. lobata samples. ConclusionThe ability of P. lobata to remove ABTS+ is stronger than that of DPPH+. There is a significant correlation between climate factors, content, and antioxidant capacity in each producing area. Further research on the internal law of the formation of medicinal active components of P. lobata induced by core climate factors will provide a scientific basis for revealing the formation mechanism of genuine P. lobata and the subsequent control of P. lobata quality according to the environment of producing areas.

11.
مقالة ي صينى | WPRIM | ID: wpr-1016487

الملخص

Cerebral ischemia-reperfusion injury (CIRI) has a very high incidence, disability, and mortality rates, which seriously affects human life and health. In recent years, modern medicine has made some progress in the diagnosis and treatment of CIRI, but there are still problems such as difficulties in postoperative rehabilitation and adverse drug reactions, and new therapeutic drugs for CIRI are urgently needed. As an important class of active ingredients in traditional Chinese medicine, flavonoids can play antioxidant, apoptosis inhibition, anti-inflammatory, and other pharmacological effects to improve brain tissue damage, which is important for improving the quality of life of CIRI patients and slowing down the aging of the social population. Numerous studies have found that flavonoids in traditional Chinese medicine can regulate cell surface receptors Toll-like receptor 4/nuclear factor-kappaB (TLR4/NF-κB), phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt), adenylate-activated protein kinase/mammalian target of rapamycin protein (AMPK/mTOR), Ras homologous gene family member A/Rho-associated coiled-coil protein kinase (RhoA/ROCK), nuclear factor E2-associated factor 2/Kelch-like epoxychloropropane-associated protein-1/haemoglobin oxygenase 1 (Nrf2/Keap1/ HO-1), Notch, and other signaling pathways, so as to regulate the transcription and expression of related proteins after CIRI, alleviate brain tissue injury, and improve CIRI. This paper analyzed the relevant literature in China and abroad in recent years, reviewed the mechanism of action and related pathways of flavonoids in traditional Chinese medicine to improve CIRI, and explored the new therapeutic direction of CIRI at the metabolic level, with a view to providing a basis for the further development and application of flavonoids in traditional Chinese medicine.

12.
Acta Pharmaceutica Sinica ; (12): 418-423, 2024.
مقالة ي صينى | WPRIM | ID: wpr-1016651

الملخص

Twelve compounds were isolated from the ethyl acetate fraction of the 80% aqueous ethanol extract of the roots and stems of Dalbergia rimosa Roxb. by silica gel, MCI, Sephadex LH-20 column chromatography, and semi-preparative HPLC. Their structures were identified by spectral analysis such as UV, IR, MS, 1D/2D NMR and by comparison with literature information as dalbergiquinol A (1), dalbergiquinol B (2), R-(-)-3′-hydroxy-2,4,5-trimethoxydalbergiquinol (3), neokhriol A (4), mucronulatol (5), (3R)-7,2′,3′-trihydroxy-4′-methoxy-isoflavane (6), isomucronulatol (7), (3S)-violanone (8), 3′-O-methylviolanone (9), eryvarin M (10), (±)-α,3,4,2′,4′-pentahydroxydihydrochalcone (11) and (-)-butin (12). Compound 1 and 2 are new compounds, and compounds 3-12 were isolated from this plant for the first time. Compounds 1, 2, 4, 6, 8, 11, 12 showed good scavenging effect on DPPH free radical.

13.
Acta Pharmaceutica Sinica ; (12): 170-182, 2024.
مقالة ي صينى | WPRIM | ID: wpr-1005440

الملخص

Thirty-one phenolic constituents were isolated and purified from the 95% ethanol extract of Sanguisorbae Radix by using various chromatographic techniques, including macroporous resin, silica gel, ODS, Sephadex LH-20 and semi-preparative HPLC. Their structures were elucidated by physicochemical properties, spectroscopic data (MS and NMR) and electronic circular dichroism (ECD) spectra, and identified as 3-methoxyl-2S,3S-epoxyflavanone (1a), 3-methoxyl-2R,3R-epoxyflavanone (1b), longifoin B (2), longifoin C (3), eriodictyol (4), naringenin (5), liquiritigenin (6), 5,3ʹ-dihydroxy-7,4ʹ-dimethoxyflavanone (7), naringenin-7-O-β-D-glucopyranoside (8), dihydroquercetin (9), dihydrokaempferol (10), (-)-garbanzol (11), (2R,3R)-4-methoxyl-distylin (12), kaempferol (13), quercetin (14), α,4,2′,4′-tetrahydroxydihydrochalcone (15), phloretin (16), (+)-catechin (17), ethyl (+)-cyanidan-3-ol-8-carboxylate (18), phyllocoumarin (19), methyl 3-methoxy-4,5-dihydroxybenzoate (20), 4,5-dimethoxy-3-hydroxybenzoic acid methyl ester (21), 3,4′-di-O-methylellagic acid (22), 3,4,3′-O-trimethylellagic acid (23), 3,3ʹ,4ʹ-O-trimethylellagic acid-4-O-β-D-xyloside (24), (3R)-thunberginol C (25), resveratrol (26), 1-hydroxypinoresinol (27), (7S,8S)-3-methoxy-3′,7-epoxy-8,4′-oxyneoligna-4,9,9′-triol (28), emodin-8-O-β-D-glucoside (29), phloracetophenone (30) and 4-(4′-hydroxyphenyl)-butan-2-one (31). Among them, compound 1a and 1b is a pair of new flavonoid enantiomers, compounds 2 and 3 are a pair of new epimers, while compounds 4, 5, 6, 9, 10, 13, 16 and 26 were obtained from S. officinalis for the first time, compounds 7, 8, 27, 30 and 31 were isolated for the first time from the S. officinalis genus, and compounds 11, 12, 15, 18, 19, 25, 28 and 29 were isolated for the first time from the Rosaceae. The antioxidant activities of compounds 1-24 were evaluated by activating the Nrf2 transcriptional pathway, which were measured by the dual-luciferase reporter gene assay in 293T cells. Compounds 4, 6-10, 12, 14, 17, 19, 20 and 22-24 showed significant Nrf2 agonistic effect compared with the control group at 25 μmol·L-1, which provided reference for the research of their antioxidant activity.

14.
مقالة ي صينى | WPRIM | ID: wpr-1006465

الملخص

Endocrine disrupting chemicals (EDCs) are a class of chemical substances widely present in daily-life environment, and can enter human body through various pathways, posing a threat to reproductive development and health. Oxidative stress (OS) is one of the most important fundamental mechanisms underlying the reproductive toxicity of EDCs. Numerous studies have found that exposure to EDCs can increase the levels of reactive oxygen species (ROS) in human reproductive system and reduce the activity and quantity of multiple enzymatic antioxidants, leading to oxidative stress and inducing damage to the reproductive system at various levels such as DNA and cells. Many research results have shown that supplementing food-derived non-enzymatic antioxidants can reduce ROS levels and increase the activity of enzymatic antioxidants, thereby reduce OS levels, and further repair EDCs-induced reproductive damage. In addition, many food-derived antioxidants are important elements involved in reproductive physiological activities and have protective effects on reproductive health. This paper summarized the reproductive toxicity of EDCs, including damage to reproductive cells, interference with hormone action, and influence on reproductive-related epigenetic regulation, elaborated the relationship between OS and reproductive toxicity of EDCs, and further summarized the alleviating effects and related mechanisms of food-derived antioxidants such as vitamins, trace elements, and plant polyphenols and pigments against reproductive toxicity of EDCs, aiming to provide a theoretical and scientific basis for prevention and treatment against reproductive toxicity of EDCs.

15.
Chinese Herbal Medicines ; (4): 151-161, 2024.
مقالة ي الانجليزية | WPRIM | ID: wpr-1010745

الملخص

OBJECTIVE@#To identify phytochemical constituents present in the extract of flowers of Xanthoceras sorbifolia and evaluate their anti-oxidant and anti-hyperglycemic capacities.@*METHODS@#The AlCl3 colorimetric method and Prussian Blue assay were used to determine the contents of total flavonoids and total phenolic acids in extraction layers, and the bioactive layers was screened through anti - oxidative activity in vitro. The Waters ACQUITY UPLC system and a Waters ACQUITY UPLC BEH C18 column (2.0 mm × 150 mm, 5 μm) were used to identify the ingredients. And anti-oxidative ingredients were screened by off-line UPLC-QTOF-MS/MS-free radical scavenging. The ameliorative role of it was further evaluated in a high-fat, streptozotocin-induced type 2 diabetic rat model and the study was carried out on NADPH oxidase (PDB ID: 2CDU) by molecular docking.@*RESULTS@#Combined with the results of activity screening in vitro, the anti - oxidative part was identified as the ethyl acetate layer. A total of 24 chemical constituents were identified by liquid chromatography-mass spectrometry in the ethyl acetate layer and 13 main anti-oxidative active constituents were preliminarily screened out through off-line UPLC-QTOF-MS/MS-free radical scavenging. In vivo experiments showed that flowers of X. sorbifolia could significantly reduce the blood glucose level of diabetic mice and alleviate liver cell damage. Based on the results of docking analysis related to the identified phytocompounds and oxidase which involved in type 2 diabetes, quercetin 3-O-rutinoside, kaempferol-3-O-rhamnoside, isorhamnetin-3-O-glucoside, and isoquercitrin showed a better inhibitory profile.@*CONCLUSION@#The ethyl acetate layer was rich in flavonoids and phenolic acids and had significant anti-oxidant activity, which could prevent hyperglycemia. This observed activity profile suggested X. sorbifolia flowers as a promising new source of tea to develop alternative natural anti-diabetic products with a high safety margin.

16.
مقالة ي صينى | WPRIM | ID: wpr-1016845

الملخص

ObjectiveThe glycosidic linkage structural characteristics of polysaccharides from Pinelliae Rhizoma(PR) and its processed products were analyzed by sugar spectrum, high performance thin layer chromatography(HPTLC), fluorescence-assisted carbohydrate gel electrophoresis(PACE) based on partial acid hydrolysis and specific glycosidase hydrolysis, and the antioxidant activities of polysaccharides before and after hydrolysis(enzymolysis) were compared. MethodPolysaccharides from PR and its processed products were extracted by ultrasound extraction, starch was hydrolyzed by α-amylase, and small molecules below 3 kDa were removed by ultrafiltration. The purified polysaccharides were prepared by hydrolysis of acid and five different specific glycosidases, and the hydrolysates were analyzed by HPTLC and PACE. The antioxidant capacity of polysaccharides was analyzed by 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)(ABTS) and 2,2-diphenyl-1-picrylhydrazyl(DPPH) free radical scavenging experiment before and after different hydrolysis. ResultThrough HPTLC and PACE analysis, it was found that polysaccharides from PR and its processed products could be hydrolyzed by β-galactosidase, β-mannase, cellulase and pectinase, but hardly hydrolyzed by glucanase, indicating that the polysaccharides contained β-galactopyranoside bond, β-1,4-mannoside bond, β-1,4-glucoside bond and α-1,4-galacturonic acid glycosidic bond. In vitro antioxidant experiments showed that the ABTS radical scavenging capacity of the polysaccharides from PR and its processed products was weakened after acid hydrolysis and pectinase enzymatic hydrolysis, while the ABTS radical scavenging capacity was enhanced after enzymatic hydrolysis with cellulase, β-galactosidase, and β-mannase. And after different hydrolysis, the DPPH free radical scavenging capacity of polysaccharides from PR and its processed products was all significantly enhanced. ConclusionThe glycosidic linkage structural characteristics of polysaccharides from PR and its processed products was analyzed by sugar spectrum in this paper, and the relationship between glycosidic bond types and their antioxidant activity was clarified through in vitro antioxidant experiments, which is beneficial for further elucidating the material basis of the related efficacy of PR and its processed products, and providing new ideas and methods for analyzing the structural characteristics of polysaccharides in Chinese medicines.

17.
مقالة ي صينى | WPRIM | ID: wpr-1016856

الملخص

Hippophae rhamnoides is a traditional Chinese medicine with homology of medicine and food, which has the effects of relieving cough and resolving phlegm, strengthening the stomach and digestion, and promoting blood circulation and resolving blood stasis. H. rhamnoides contains not only flavonoids, phenols, proteins, vitamins, and amino acids but also abundant polysaccharides. In order to explore the functional value and current research status of H. rhamnoides polysaccharides, this study systematically summarized the extraction process, structural characteristics, pharmacological effects, and mechanism of action of H. rhamnoides polysaccharides by reviewing Chinese and foreign literature. The results showed that H. rhamnoides polysaccharides have anti-tumor, hypoglycemic, antioxidant, immune regulation, anti-inflammatory, and anti-hyperlipidemia functions and could improve intestinal microbiota. There were various extraction processes for polysaccharides, including hot water extraction, microwave extraction, ultrasonic extraction, enzymatic extraction, flash extraction, ultrasonic-microwave synergistic extraction, emerald hot water extraction, enzymatic-ultrasonic synergistic extraction, etc. Based on comprehensive analysis, hot water extraction is suitable for industrial development and application. However, multiple homogeneous polysaccharides have been isolated and purified from H. rhamnoides polysaccharides, but their efficacy, structure, and structure-activity relationship still need to be further explored and studied. This study can provide a reference for the research and development of H. rhamnoides polysaccharides.

18.
Chinese Journal of Analytical Chemistry ; (12): 45-53,中插5-中插13, 2024.
مقالة ي صينى | WPRIM | ID: wpr-1017628

الملخص

Lattice strain ruthenium nanoparticles uniformly and stably supported on nitrogen-modified carbon nanosheets(RuNPs/NC)were prepared via simple wet-chemical and subsequent pyrolysis method.The nitrogen doped NC could effectively improve their uniform dispersion and lattice compression of RuNPs.Through changing the pyrolysis temperature,the nitrogen content,types and degree of lattice strain of RuNPs could be effectively tuned,which could be used to adjust and control their peroxidase-like activity.The as-prepared RuNPs/NC-900 exhibited highest peroxidase-like activity,and could catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine(TMB)to produce a blue product with the maximum absorption at 652 nm in the presence of H2O2.The steady-state kinetic analysis indicated that the reaction catalyzed by RuNPs/NC followed the Michaelis-Menten kinetic model.Tannic acid(TA),gallic acid(GA)and ascorbic acid(AA)could effectively inhibit the RuNPs/NC-H2O2-triggered chromogenic reaction of TMB,resulting in color fading and decrease in absorbance.Based on this,a sensitive and accurate system was constructed for detection of TA,GA and AA.The detection limits(3σ/S)for TA,GA and AA were 0.014,0.014 and 0.29 μmol/L,respectively.This study not only developed a colorimetric sensing method based on RuNPs/NC nanozyme but also offered a new approach for the sensitive detection of antioxidants in food.

19.
Journal of Preventive Medicine ; (12): 345-349, 2024.
مقالة ي صينى | WPRIM | ID: wpr-1038927

الملخص

Objective@#To investigate the causal relationship between antioxidant nutrients and pregnancy complications, so as to provide the reference for the prevention and treatment of pregnancy complications.@*Methods@#Data of seven antioxidant nutrients including vitamin A, vitamin C, vitamin E, selenium, zinc, copper and iron were collected from genome-wide association study (GWAS) Catalog database, and data of four pregnancy complications including gestational diabetes mellitus, pre-eclampsia, spontaneous abortion and preterm birth were collected from the Finland database. Single nucleotide polymorphism (SNP) data were collected, and 27 SNPS strongly correlated with seven antioxidant nutrients were selected as instrumental variables. Mendelian randomization (MR) analyses were performed using the inverse-variance weighted (IVW) method with seven antioxidant nutrients as exposures factors and four pregnancy complications as outcome variables. The heterogeneity was assessed using the Cochran's Q test, the horizontal pleiotropy was assessed using the MR-PRESSO test and MR-Egger regression, and the robustness of the results was verified with the leave-one-out.@*Results@#Cochran's Q test showed heterogeneity of MR results between vitamin C and gestational diabetes mellitus, preeclampsia and preterm birth, between vitamin E and iron and gestational diabetes (all P<0.05), and a random effect model was employed. There was no heterogeneity in other results (all P>0.05), and a fixed effect model was employed. MR analysis results showed that there was no causal association between seven antioxidant nutrients and the risk of four pregnancy complications (all P>0.05). MR-PRESSO test and the MR-Egger regression identified no horizontal pleiotropy of instrumental variables (both P>0.05).@*Conclusion@#This study did not find genetically predicted associations of antioxidant nutrients with pregnancy complications.

20.
Journal of Preventive Medicine ; (12): 365-368, 2024.
مقالة ي صينى | WPRIM | ID: wpr-1038932

الملخص

Objective@#To explore the effects of whole wheat flour on blood glucose and lipid levels and antioxidant capacity of high-fat fed mice.@*Methods@#Thirty-two male C57BL/6J mice at ages of 3 to 4 weeks were randomly divided into 4 groups with 8 mice in each group. The normal control group was fed with ordinary diet, the high-fat diet group was fed with high-fat diet, the whole wheat flour group was fed with high-fat diet and whole wheat flour, and the refined wheat flour group was fed with high-fat diet and refined wheat flour. Nine weeks later, blood was collected from the tail for measurement of fasting blood glucose (FBG), and blood was also collected from the eyeball to determine the levels of total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA). Adipose tissue was taken and weighed after death. Body weight, total food intake, Lee's index, adipose index, blood glucose, blood lipids, and antioxidant indicators were compared among the four groups of mice.@*Results@#Compared with the normal control group, the mice in the high-fat diet group, whole wheat flour group, and refined wheat flour group exhibited increased body weight, total food intake, Lee's index, and adipose index, as well as decreased GSH-Px levels; the high-fat diet group had elevated levels of TC, TG, LDL-C and MDA (all P<0.05). When compared to the high-fat diet group, the whole wheat flour group showed lower Lee's index and adipose index, but the difference was not statistically significant (both P>0.05). Both the whole wheat flour group and the refined wheat flour group had reduced levels of TC, TG, LDL-C, and MDA, as well as increased GSH-Px levels (all P<0.05).@*Conclusions@#Whole wheat flour can effectively reduce the body weight of high-fat feeding mice, improve blood lipid levels, and enhance antioxidant capacity. However, there was no significant difference in the effects of whole wheat flour and refined wheat flour on mice during the experimental period.

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