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1.
Molecules ; 27(10)2022 May 20.
Article in English | MEDLINE | ID: mdl-35630757

ABSTRACT

One of the main global problems that affect human health is the development of bacterial resistance to different drugs. As a result, the growing number of multidrug-resistant pathogens has contributed to an increase in resistant infections and represents a public health problem. The present work seeks to investigate the chemical composition and antibacterial activity of the essential oil of Syzygium cumini leaves. To identify its chemical composition, gas chromatography coupled to mass spectrometry was used. The antibacterial activity test was performed with the standard strains Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 25853 and Staphylococcus aureus ATCC 25923 and multidrug-resistant clinical isolates E. coli 06, P. aeruginosa 24 and S. aureus 10. The minimum inhibitory concentration (MIC) was determined by serial microdilution as well as the verification of the modulating effect of the antibiotic effect. In this test, the oil was used in a subinhibitory concentration. The test reading was performed after 24 h of incubation at 37 °C. The results show that the major chemical constituent is α-pinene (53.21%). The oil showed moderate activity against E. coli ATCC 25922, with the MIC of 512 µg/mL; there was no activity against the other strains. The oil potentiated the effect of antibiotics demonstrating possible synergism when associated with gentamicin, erythromycin and norfloxacin against E. coli 06 and S. aureus 10.


Subject(s)
Oils, Volatile , Syzygium , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Escherichia coli , Gas Chromatography-Mass Spectrometry , Humans , Oils, Volatile/chemistry , Oils, Volatile/pharmacology , Phytochemicals/pharmacology , Pseudomonas aeruginosa , Staphylococcus aureus
2.
Ecotoxicol Environ Saf ; 170: 461-467, 2019 Apr 15.
Article in English | MEDLINE | ID: mdl-30553924

ABSTRACT

The objective of this work was to evaluate the antioxidant, metal chelating and cytoprotective activity of the Eugenia jambolana Lam. extract, as well as of its flavonoid and tannic fractions, against the action of Mercury Chloride (HgCl2). Flavonoids were quantified and an LC-MS chromatographic analysis was performed to identify secondary metabolites. Fe2+ and Fe3+ chelation tests and antioxidant activity were carried out using the FRAP method. Microbiological tests were performed by microdilution to determine the Minimum Inhibitory Concentration (MIC). From these results the Minimum Bactericidal (MBC) and Minimum Fungicide Concentration (MFC) were evaluated. The allelopathy and cytoprotection assays were performed using eukaryotic and prokaryotic models. The results revealed the presence of phenolic acids and flavonoids in the E. jambolana extract and fractions. The sub-allelopathic concentration (64 µg/mL) was used and the results demonstrated the E. jambolana potential cytoprotective effect against mercury chloride.


Subject(s)
Biological Products/chemistry , Mercuric Chloride/toxicity , Syzygium/chemistry , Allelopathy , Anti-Infective Agents/chemistry , Antioxidants/chemistry , Cytoprotection , Flavonoids/chemistry , Lactuca/drug effects , Microbial Sensitivity Tests , Plant Extracts/chemistry
3.
J Photochem Photobiol B ; 174: 144-149, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28778018

ABSTRACT

Bacterial resistance has risen as an important health problem with impact on the pharmaceutical industry because many antibiotics have become ineffective, which has affected their commercialization. The Brazilian biodiversity is marked by a vast variety of natural products with significant therapeutic potential, which could bring new perspectives in the treatment of infections caused by resistant microorganisms. The present study aimed to evaluate the antibacterial effect of the essential oil obtained from Eugenia jambolana (EjEO) using the method of microdilution method to determine the Minimum Inhibitory Concentration (MIC). The modulatory effect of this oil on antibiotic activity was determined using both the broth microdilution and gaseous contact methods. The antibacterial effect of the association of the gaseous contact and the use of a LED unit with red and blue lights was also determined. The chemical components of the EjEO were characterized by HPLC, which revealed the presence of α-pinene as a major constituent. The EjEO presented a MIC≥128µg/mL against S. aureus and ≥1024µg/mL against E. coli. The combination of the EjEO with antibiotics presented synergism against E. coli and antagonism against S. aureus. An antagonistic effect was obtained from the association of EjEO with amikacin and erythromycin by the method of gaseous contact. On the other hand, the association of EjEO with ciprofloxacin presented a synergistic effect against S. aureus and E. coli exposed to LED lights. A similar effect was observed in the association of the EjEO with norfloxacin presented synergism against S. aureus in the same conditions. In conclusion, our results demonstrated that the essential oil obtained from Eugenia jambolana interfere with the action of antibiotics against bacteria exposed to LED lights. Thus, further researches are required to elucidate the mechanisms underlying these effects, which could open new perspectives in the development of new antibacterial therapies.


Subject(s)
Anti-Bacterial Agents/pharmacology , Light , Oils, Volatile/pharmacology , Plant Oils/pharmacology , Syzygium/chemistry , Escherichia coli/drug effects , Escherichia coli/radiation effects , Microbial Sensitivity Tests , Staphylococcus aureus/drug effects , Staphylococcus aureus/radiation effects
4.
Acta toxicol. argent ; 24(3): 187-192, dic. 2016. ilus, tab
Article in Spanish | LILACS | ID: biblio-837865

ABSTRACT

La evaluación de la actividad antioxidante ha sido una cuestión relevante teniendo en cuenta su importancia para la salud humana. Estudios recientes muestran que el uso de plantas en forma de jugos o tés como fuentes de antioxidantes naturales, que se pueden utilizar como complemento para el tratamiento de diversas enfermedades. En este contexto, evaluado el potencial antioxidante in vitro, de extractos de Eugenia jambolana Lam y Psidium myrsinites DC. A. y cuantificar fenoles y flavonoides presentes en los extractos. La peroxidación lipídica ha sido evaluada por la técnica de TBARS (sustancias reactivas al ácido tiobarbitúrico). De acuerdo con los resultados, mostraron una mejor actividad antioxidante del extracto de psidium myrsinites DC. A. Para poner a prueba TBARS con fosfolípido de huevo extrae redujo los niveles basales en el proceso de peroxidación de lípidos, la CI50 del extracto etanolico de Euguenia jambolana (EEFEJ) mostró los mejores resultados, con un más bajo valor de la CI50 en comparación con el extracto hidroetanolico de Psidium mirsinites, demostrado ser más efectivo. Por lo tanto, a través de estas pruebas se puede ver que los extractos de las hojas de la especie, Eugenia jambolana Lam y Psidium myrsinites DC. A., la actividad antioxidante de exposiciones, sustancias fenólicas directamente relacionados producidos a partir de su metabolismo secundario.


The evaluation of the antioxidant activity has been a relevant and important issue to human health. Recent studies show that the use of plants juices or teas as sources of natural antioxidants, which can be used as an adjuvant in the treatment of several diseases. In this context, was evaluated the in vitro antioxidant potential of the extracts of Psidium myrsinites DC. and Eugenia jambolana Lam. The total of phenols and flavonoids were quantified in the extracts. Lipid peroxidation was evaluated by the technique of TBARS (thiobarbituric acid reactive substances). According to the results, was showed a better antioxidant activity in the extract of Psidium myrsinites DC. A. In the TBARS assay with egg phospholipid the extracts reduced the basal levels in the process of lipid peroxidation and the IC50 of ethanol extract of Eugenia jambolana (EEFEJ) showed the best results with a lower value of IC50 compared with hydroethanol extract of Psidium mirsinites, demonstrating be more effective. Therefore, through these tests can be seen that extracts from the leaves of the species, Eugenia and Psidium jambolana Lam myrsinites DC. A., exhibit antioxidant activity, directly related phenolic substances produced from the secondary metabolism.


Subject(s)
Humans , Antioxidants/chemical synthesis , Eugenia jambosa/therapeutic use , Lipid Peroxidation/drug effects , Psidium/drug effects , Phytochemicals/therapeutic use , Plant Extracts/therapeutic use
5.
Rev. bras. farmacogn ; 23(4): 651-661, Aug. 2013. ilus, tab
Article in English | LILACS | ID: lil-686642

ABSTRACT

Eugenia jambolana Lam., Myrtaceae, is a widely distributed and traditionally well known plant in India. The root bark of the plant was extracted with ethanol and then successively fractionated into petroleum ether fraction, chloroform fraction, n-butanol fraction and methanol fraction. The extract and fractions of the plant material were evaluated for the antinociceptive activity by acetic acid-induced writhing test and formalin-induced nociception test, and anti-inflammatory activity was screened by carrageenan-induced rat paw edema, cotton pellet induced granuloma formation and adjuvant induced arthritis in rat models. The test materials showed the antinociceptive and anti-inflammatory effect in dose dependent manner and the petroleum ether fraction was found to be most potent among the test materials. At 400 mg/kg b.w., p.o. dose petroleum ether fraction significantly inhibited 54.28% writhing response and 73.77% formalin induced nociception in mice. The fraction with same dose showed significant 79.31% inhibition of carrageenan-induced rat paw edema, 57.78% anti-proliferative effect and 77.93% inhibition of adjuvant induced arthritis. The bioactive petroleum ether fraction was then subjected to column chromatography which led to isolate three compounds, namely, β-sitosterol, stigmasterol and lupeol. These compounds were characterized and identified by IR, ¹H NMR, 13C NMR and mass spectroscopy.

6.
Rev. bras. farmacogn ; 23(1): 145-152, Jan.-Feb. 2013. graf, tab
Article in English | LILACS | ID: lil-666174

ABSTRACT

Aqueous extract from seeds of Syzygium cumini (L.) Skeels, Myrtaceae, obtained by dynamic maceration was spray-dried and characterized by its physico-chemical and antihyperglycaemic action. The extract showed to possess high amount of polyphenols, significant in vitro free radical scavenger activity using the DPPH method and an antihyperglycaemic effect in alloxan-induced experimental diabetes. S. cumini spray-dried extracts were obtained using silicon dioxide and cassava starch as adjuvants. The powders showed acceptable flowability, compactability, and low hygroscopicity at 43% relative humidity. Besides, the spray-dried extracts showed in vivo antihyperglycaemic and in vitro scavenger activity comparable to the lyophilized extract. Thus, experimental data indicates that the extract from S. cumini has a relevant activity and that spray-drying could be adequately used to perform the technological processing of S. cumini fluid extracts.

7.
Rev. bras. farmacogn ; 11(1): 37-50, 2001. ilus, tab
Article in Portuguese | LILACS | ID: lil-528790

ABSTRACT

A padronização de um fitoterápico é etapa imprescindível para garantia da qualidade de medicamentos contendo plantas medicinais. Objetivou-se padronizar Syzygiam cumini (L.) Skeels e para tanto se estabeleceram parametros tais como, avaliação morfoanatômica das folhas, morfológica das flores e dos frutos, avaliação granulométrica da droga rasurada (frutos), determinação da umidade, avaliação dos processos de secagem, determinação do teor de extrativos e do teor de taninos (monômeros e polimeros). O estudo anatômico das folhas revelou a inexistência de pêlos no sistema dérmico, assim como a ocorrência de glândulas secretoras, drusas, colênquima e esclerênquima. As flores são hermafroditas, com androceu polistêmone e gineceu com ovário ínfero, gamocarpelar, bilocular com placentação axial. Observou-se elevado teor extrativo (38,57 por cento). O diâmetro médio de partícula dos frutos secos moídos ficou em 0,630 mm. O processo de secagem dos frutos influenciou o teor de taninos totais. O teor de taninos determinado ficou em 5,10 por cento para monômeros e 11,30 por cento para os polimeros.


The phytotherapics standardization is an important step for the warranty of the quality of the drugs contends medicinal plants. The aim of this paper was to standardize and establish parameters seeking the characterization of the drug, according to technical pharmacopoeias and in some cases, other techniques were developed. Morphologic description of leaves, flowers and fruits, granulometric analysis of the ground drugs, dry residues, evaluations in the drying methods, determination of the extractive drift and tannins values (monomers and polymers) were executed, being the monomers in the range of 5,10 percent and 11,30 percent for the polymeric ones.

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