scholarly journals Coordination Compounds of Platinum and Palladium with Mixed Ligands (Usnic Acid and 1-(o-Tolyl) Biguanide) � Synthesis, Spectral Characterization and Biological Activity

2020 ◽  
Vol 71 (4) ◽  
pp. 336-346
Author(s):  
Mirela Calinescu ◽  
Ovidiu Oprea ◽  
Catalina Stoica ◽  
Mihai Nita-Lazar ◽  
Madalina Mihalache
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Biological Activity ◽  
Coordination Compounds ◽  
Antitumor Agents ◽  
Biological Activities ◽  
Usnic Acid ◽  
Biological Properties ◽  
Mixed Ligands

Four coordination compounds of Pd(II), Pt(II) and Pt(IV) with usnic acid (H3AU) and 1-(o-tolyl)biguanide (TB) as ligands have been synthesized in view of their potential as antimicrobial, antifungal and antitumor agents. The metal complexes have been characterized by elemental and thermogravimetrical analyses, infrared and electronic spectra. Based on these studies, the following formulas have been proposed for the complexes: [Pd(TB)(H3AU)]PdCl4 (C1), [Pd(TB)(H2AU)] CH3COO (C2), [Pt(TB)(H2AU)Cl2]Cl (C3) and [Pt(TB)(H2AU)]Cl (C4), where H2AU is deprotonated usnic acid. The in vitro biological activities of the new complexes were tested against Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Candida albicans ATCC 10231 and HeLa tumor cells. All complexes were found to have good biological properties and therefore they can be further explored in therapeutic applications.

scholarly journals Analytics on Antimicrobial Activity of Lichen Extract

2021 ◽  
Author(s):  
Hitendra Yadav ◽  
Sanjeeva Nayaka ◽  
Manish Dwivedi
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Ethyl Acetate ◽  
Methanolic Extract ◽  
Biological Activities ◽  
Usnic Acid ◽  
Human Pathogens ◽  
Fungal Partner

Lichen has a great medicinal value and represents the symbiotic relationship between fungi and algae or cyanobacteria. The genus Usnea longissima (Parmeliaceae), is a fruticose lichen with numerous biological activities like antimicrobial, antifungal and inhibitory activities for plant and human pathogens. Taxonomically it is well distinguished by pale greenish to yellowish-green colour and pendulous thallus with dense branches usually emerging from the main stem. Its fungal partner releases an extracellular compound called Usnic acid, a derivative of Dibenzofuran which is a naturally occurring secondary metabolite. In the present work, antimicrobial activities of Usnea longissimi are explored in various extraction solvents. The crude extracts were prepared in methanol, ethanol, ethyl acetate, acetone and different concentrations (2.5,5,10,15,20mg/ml) followed by the determination of its antimicrobial activity against various microbes viz. Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Fusarium oxysporum using agar well diffusion process. The maximum zone of inhibition was observed in the 15 mg/ml methanolic extract for Escherichia coli(34 mm), 10 mg/ml methanolic extract for Staphylococcus aureus (30 mm), 10 mg/ml ethyl acetate for Pseudomonas aeruginosa (16 mm) and 0.5 mg/ml ethanolic extract for Fusariumoxysporium (14 mm). Usnea longissimi have shown significant antibacterial and antifungal activity that encourage us to explore novel antimicrobial components within lichen biodiversity. These lichens further can be used as food supplements to cure various human diseases.

scholarly journals Antibacterial activity tannin-rich fraction from leaves of Anacardium humile

2012 ◽  
Vol 42 (10) ◽  
pp. 1861-1864 ◽  
Author(s):  
Peracio Rafael Bueno Ferreira ◽  
Cíntia Sorandra Oliveira Mendes ◽  
Cínthia Gracielly Rodrigues ◽  
Juliane Caroline Moura Rocha ◽  
Vanessa de Andrade Royo ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Enterococcus Faecalis ◽  
Antibacterial Agents ◽  
Biological Activities ◽  
In Vitro Tests ◽  
Leaf Extracts ◽  
Minimal Inhibitory Concentrations

In vitro tests conducted with extracts rich in tannins have identified several biological activities of this class of substance. Thus, this paper intends to evaluate the antibacterial activity of tannin-rich fraction obtained from leaf extracts of Anacardium humile A.St.-Hil. Extracts of A. humile leaves in 70% acetone were semi-purified with ethyl acetate and butanol. We quantified the total tannins of the semi-purified fractions, of the crude extract and of aqueous residues and then performed tests of the antibacterial activity of the tannins against Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212. All positive extracts underwent tannin isolation using a Sephadex LH-20 column. The tannins isolated from the samples were quantified and tested for the minimal inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC). The tannins from crude extracts, semi-purifications and residues showed inhibition of S. aureus growth with MIC=500 g mL-1. All tannin fractions showed MIC against all strains and MBC, except against E. faecalis. The tannin fractions from Anacardium humile have antibacterial activity against Staphylococcus aureus, Pseudomononas aeruginosa and Enterococcus faecalis and, therefore, may be promising for future synthesis of new antibacterial agents.

ATIVIDADE ANTIMICROBIANA IN VITRO DO EXTRATO AQUOSO, HIDROALCOÓLICO E ALCOÓLICO DE FOLHAS DE ESPÉCIES DA FAMÍLIA LAMIACEAE

2018 ◽  
Vol 4 ◽  
Author(s):  
Karlynne Freire Mendonça ◽  
José Klauber Roger Carneiro ◽  
Maria Auxiliadora Silva Oliveira
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Enterococcus Faecalis ◽  
Streptococcus Pyogenes ◽  
Mentha Arvensis ◽  
Ocimum Gratissimum ◽  
Mueller Hinton ◽  
Plectranthus Amboinicus

Objetivos: avaliar a atividade antimicrobiana em extrato aquoso, hidroalcoólico e alcoólico das folhas de espécies da família Lamiaceae frente a bactérias de interesse. Método: Foram escolhidas quatro espécies: Ocimum gratissimum, Plectranthus amboinicus, Mentha arvensis e Plectranthus barbatus. A partir das folhas foram confeccionados os extratos aquoso, hidroalcoólico e alcoólico nas concentrações 100mg/mL, 50mg/mL e 25mg/mL. Foram selecionadas as bactérias Streptococcus pyogenes, Enterococcus faecalis, Staphylococcus aureus e Pseudomonas aeruginosa para os ensaios de antibiose em Ágar Mueller-Hinton. Resultados: P. barbatus, em seu extrato hidroalcoólico mostrou ativo nas três concentrações para bactéria S. aureus, e ainda foi ativo para P. aeruginosa, demonstrando no extrato alcoólico atividade frente as bactérias. Para M. arvensis e P. amboinicus, seus extratos hidroalcoólico e alcoólico apresentaram atividade para S. aureus. Conclusão: Sugere-se que as espécies em questão apresentem boa atividade antimicrobiana, sendo necessária a realização de mais estudos para melhor entender esse mecanismo.

Activité antibactérienne de l’huile essentielle de Pelargonium x asperum et son potentiel synergique avec la nisine

2019 ◽  
Vol 17 (3) ◽  
pp. 140-148 ◽  
Author(s):  
A. Ouelhadj ◽  
L. Ait Salem ◽  
D. Djenane
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Klebsiella Pneumoniae ◽  
Nous Avons ◽  
Activité Antibactérienne

Ce travail vise l’étude de l’activité antibactérienne de l’huile essentielle (HE) de Pelargoniumx asperum et de la bactériocine, la nisine seul et en combinaison vis-à-vis de six bactéries dont quatre sont multirésistantes d’origine clinique. L’activité antibactérienne in vitro a été évaluée par la méthode de diffusion sur gélose. La concentration minimale inhibitrice (CMI) est aussi déterminée pour HE. Les résultats ont révélé une activité antibactérienne significative exercée par HE visà-vis de Staphylococcus aureus (ATCC 43300), Staphylococcus aureus et Escherichia coli avec des diamètres d’inhibition de 36,00 ; 22,50 et 40,00 mm, respectivement. Cependant, l’HE de Pelargonium asperum a montré une activité antibactérienne supérieure par rapport à la nisine. Les valeurs des CMI rapportées dans cette étude sont comprises entre 1,98–3,96 μl/ml. Les combinaisons réalisées entre HE et la nisine ont montré un effet additif vis-à-vis de Escherichia coli (ATCC 25922) avec (50 % HE Pelargonium asperum + 50 % nisine). Par contre, nous avons enregistré une synergie vis-à-vis de Klebsiella pneumoniae avec (75 % HE Pelargonium asperum + 25 % nisine) et contre Pseudomonas aeruginosa avec les trois combinaisons testées. Les résultats obtenus permettent de dire que l’HE de Pelargonium asperum possède une activité antibactérienne ainsi que sa combinaison avec la nisine pourrait représenter une bonne alternative pour la lutte contre l’antibiorésistance.

Complexes of Cu (II) with a-Ketoglutaric Acid and 1- (o-tolyl) Biguanide Synthesis, characterization and biological Activity

2019 ◽  
Vol 70 (10) ◽  
pp. 3603-3610
Author(s):  
Madalina Mihalache ◽  
Cornelia Guran ◽  
Aurelia Meghea ◽  
Vasile Bercu ◽  
Ludmila Motelica ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Biological Activity ◽  
Candida Albicans ◽  
Antifungal Activity ◽  
Copper Complexes ◽  
Substrate Adhesion ◽  
Inert Substrate

The three copper complexes having a-ketoglutaric acid (H2A) and 1- (o-tolyl) biguanide (TB) ligands have been synthesized and characterized. The proposed formulas for these complexes are: [Cu(TB)(HA)]Cl (C1), [Cu(TB)(HA)CH3COO]�H2O (C2) and [Cu(TB)(HA)](NO3) (C3) where HA represents deprotonated H2A. The complexes obtained were tested for antibacterial activity against Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853, antifungal activity on Candida albicans ATCC 10231 and antitumor activity on HeLa tumor cells. Due to the antitumor, antifungal, antimicrobial activity and inhibition of inert substrate adhesion, complexes synthesized could be used for potential therapeutic applications.

Tamarix articulata (T. articulata) - An Important Halophytic Medicinal Plant with Potential Pharmacological Properties

2019 ◽  
Vol 20 (4) ◽  
pp. 285-292 ◽  
Author(s):  
Abdullah M. Alnuqaydan ◽  
Bilal Rah
Keyword(s):  
Medicinal Plant ◽  
Biological Activities ◽  
Wide Spectrum ◽  
Biological Properties ◽  
In Vivo Model ◽  
Drug Candidate ◽  
Phytochemical Analysis ◽  
Pharmacological Properties

Background:Tamarix Articulata (T. articulata), commonly known as Tamarisk or Athal in Arabic region, belongs to the Tamaricaece species. It is an important halophytic medicinal plant and a good source of polyphenolic phytochemical(s). In traditional medicines, T. articulata extract is commonly used, either singly or in combination with other plant extracts against different ailments since ancient times.Methods:Electronic database survey via Pubmed, Google Scholar, Researchgate, Scopus and Science Direct were used to review the scientific inputs until October 2018, by searching appropriate keywords. Literature related to pharmacological activities of T. articulata, Tamarix species, phytochemical analysis of T. articulata, biological activities of T. articulata extracts. All of these terms were used to search the scientific literature associated with T. articulata; the dosage of extract, route of administration, extract type, and in-vitro and in-vivo model.Results:Numerous reports revealed that T. articulata contains a wide spectrum of phytochemical(s), which enables it to have a wide window of biological properties. Owing to the presence of high content of phytochemical compounds like polyphenolics and flavonoids, T. articulata is a potential source of antioxidant, anti-inflammatory and antiproliferative properties. In view of these pharmacological properties, T. articulata could be a potential drug candidate to treat various clinical conditions including cancer in the near future.Conclusion:In this review, the spectrum of phytochemical(s) has been summarized for their pharmacological properties and the mechanisms of action, and the possible potential therapeutic applications of this plant against various diseases discussed.

Exploración de la actividad antibacteriana de Metformina frente a Escherichia coli, Staphylococcus aureus y Pseudomonas aeruginosa

Bionatura ◽  
2020 ◽  
Vol 5 (4) ◽  
pp. 1335-1339
Author(s):  
Pool Marcos-Carbajal ◽  
Christian Allca-Muñoz ◽  
Ángel Urbano-Niño ◽  
Alberto Salazar-Granara
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa

El objetivo del estudio es determinar la actividad antibacteriana de Metformina frente a Escherichia coli, Staphylococcus aureus y Pseudomonas aeruginosa. Se evaluó la actividad antibacteriana mediante la técnica de Kirby Bauer. Se utilizó cepas de Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923) y Pseudomonas aeruginosa (ATCC 27853), las cuales se expusieron a Metformina en concentraciones de 250 mg y 500 mg, Ciprofloxacino (CIP) 5 µg, Imipenem (IPM) 10 µg, y Cefoxitin (FOX) 30 µg. Frente a Escherichia coli, Staphylococcus aureus y Pseudomonas aeruginosa se presentó un halo de inhibición de 6 mm. para Metformina 250 mg, 6 mm. para Metformina 500 mg, y un halo de inhibición >25 mm. con el uso de Ciprofloxacino 5 µg, Cefoxitin 30 µg, e Imipenem 10 µg respectivamente. En conclusion, In vitro Metformina a dosis de 250 y 500 mg, no presentó efecto antibacteriano frente a Escherichia coli, Staphylococcus aureus y Pseudomonas aeruginosa.

scholarly journals Exogenous Alginate Protects Staphylococcus aureus from Killing by Pseudomonas aeruginosa

2019 ◽  
Vol 202 (8) ◽  
Author(s):  
Courtney E. Price ◽  
Dustin G. Brown ◽  
Dominique H. Limoli ◽  
Vanessa V. Phelan ◽  
George A. O’Toole
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Physical Space ◽  
Late Time ◽  
Protective Effects ◽  
Content Type ◽  
Alginate Production ◽  
The Impact

ABSTRACT Cystic fibrosis (CF) patients chronically infected with both Pseudomonas aeruginosa and Staphylococcus aureus have worse health outcomes than patients who are monoinfected with either P. aeruginosa or S. aureus. We showed previously that mucoid strains of P. aeruginosa can coexist with S. aureus in vitro due to the transcriptional downregulation of several toxic exoproducts typically produced by P. aeruginosa, including siderophores, rhamnolipids, and HQNO (2-heptyl-4-hydroxyquinoline N-oxide). Here, we demonstrate that exogenous alginate protects S. aureus from P. aeruginosa in both planktonic and biofilm coculture models under a variety of nutritional conditions. S. aureus protection in the presence of exogenous alginate is due to the transcriptional downregulation of pvdA, a gene required for the production of the iron-scavenging siderophore pyoverdine as well as the downregulation of the PQS (Pseudomonas quinolone signal) (2-heptyl-3,4-dihydroxyquinoline) quorum sensing system. The impact of exogenous alginate is independent of endogenous alginate production. We further demonstrate that coculture of mucoid P. aeruginosa with nonmucoid P. aeruginosa strains can mitigate the killing of S. aureus by the nonmucoid strain of P. aeruginosa, indicating that the mechanism that we describe here may function in vivo in the context of mixed infections. Finally, we investigated a panel of mucoid clinical isolates that retain the ability to kill S. aureus at late time points and show that each strain has a unique expression profile, indicating that mucoid isolates can overcome the S. aureus-protective effects of mucoidy in a strain-specific manner. IMPORTANCE CF patients are chronically infected by polymicrobial communities. The two dominant bacterial pathogens that infect the lungs of CF patients are P. aeruginosa and S. aureus, with ∼30% of patients coinfected by both species. Such coinfected individuals have worse outcomes than monoinfected patients, and both species persist within the same physical space. A variety of host and environmental factors have been demonstrated to promote P. aeruginosa-S. aureus coexistence, despite evidence that P. aeruginosa kills S. aureus when these organisms are cocultured in vitro. Thus, a better understanding of P. aeruginosa-S. aureus interactions, particularly mechanisms by which these microorganisms are able to coexist in proximal physical space, will lead to better-informed treatments for chronic polymicrobial infections.

scholarly journals Staphylococcus aureus Serves as an Iron Source for Pseudomonas aeruginosa during In Vivo Coculture

2005 ◽  
Vol 187 (2) ◽  
pp. 554-566 ◽  
Author(s):  
Lauren M. Mashburn ◽  
Amy M. Jett ◽  
Darrin R. Akins ◽  
Marvin Whiteley
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Pathogenic Bacteria ◽  
Iron Acquisition ◽  
Low Oxygen ◽  
Dialysis Membrane ◽  
Opportunistic Human Pathogen ◽  
The Impact

ABSTRACT Pseudomonas aeruginosa is a gram-negative opportunistic human pathogen often infecting the lungs of individuals with the heritable disease cystic fibrosis and the peritoneum of individuals undergoing continuous ambulatory peritoneal dialysis. Often these infections are not caused by colonization with P. aeruginosa alone but instead by a consortium of pathogenic bacteria. Little is known about growth and persistence of P. aeruginosa in vivo, and less is known about the impact of coinfecting bacteria on P. aeruginosa pathogenesis and physiology. In this study, a rat dialysis membrane peritoneal model was used to evaluate the in vivo transcriptome of P. aeruginosa in monoculture and in coculture with Staphylococcus aureus. Monoculture results indicate that approximately 5% of all P. aeruginosa genes are differentially regulated during growth in vivo compared to in vitro controls. Included in this analysis are genes important for iron acquisition and growth in low-oxygen environments. The presence of S. aureus caused decreased transcription of P. aeruginosa iron-regulated genes during in vivo coculture, indicating that the presence of S. aureus increases usable iron for P. aeruginosa in this environment. We propose a model where P. aeruginosa lyses S. aureus and uses released iron for growth in low-iron environments.

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