scholarly journals Novel synthetic antimicrobial peptides effective against methicillin-resistant Staphylococcus aureus

1994 ◽  
Vol 302 (2) ◽  
pp. 535-538 ◽  
Author(s):  
J Alvarez-Bravo ◽  
S Kurata ◽  
S Natori
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Candida Albicans ◽  
Liquid Medium ◽  
Culture Medium ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Antimicrobial Activities ◽  
Methicillin Resistant ◽  
Synthetic Antimicrobial Peptides

Previously, we identified a core undecapeptide of sapecin B having antimicrobial activity. Based on the structure of this peptide, we systematically synthesized peptides consisting of terminal basic motifs and internal oligo-leucine sequences and examined their antimicrobial activities. Of these peptides, RLKLLLLLRLK-NH2 and KLKLLLLLKLK-NH2 were found to have potent microbicidal activity against Staphylococcus aureus, Escherichia coli, methicillin-resistant S. aureus and Candida albicans in liquid medium. We also synthesized the D-enantiomer of KLKLLLLLKLK-NH2. This enantiomer was resistant to tryptic digestion and persisted longer in the culture medium, showing greater antimicrobial activity than the original peptide.

scholarly journals PREPARATION OF COLD CREAM AGAINST CLINICAL PATHOGEN USING CARALLUMA ADSCENDENS VAR. ATTENUATA

2020 ◽  
pp. 120-123
Author(s):  
SUNDAR MADASAMY ◽  
SURESH SUNDAN ◽  
LINGAKUMAR KRISHNASAMY
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Positive Control ◽  
Diffusion Method ◽  
Methicillin Resistant ◽  
Cold Cream ◽  
Significant Difference ◽  
Vancomycin Resistant

Objective: A simple formulation of cold cream from methanolic extract Caralluma adscendens var. attenuata (MECA) and their antimicrobial activity was tested against various clinical pathogens, namely, Escherichia coli, methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium, and Candida albicans. Methods: Methanol extract of these plant extract was prepared by the Soxhlet method. We analyzed phytochemical nature of theses plant, and subsequently, a cream was formulated cold-cream C. adscendens var. attenuata (FCA) different concentration such as FCA 50 mg, FCA 100 mg, and FCA 200 mg. In the present study, aimed to the antimicrobial activity of cold cream was measured by agar well diffusion method, and standard antibiotic Neosporin (market available) cream was used as positive control and dummy cold cream (without-MECA) were used as the negative control. Results: Phytochemical screening showed that the plant extracts were found a rich source of secondary metabolites. For more, the efficacy of cold cream from MECA extracts to against the clinical pathogen. Positive control Neosporin and 200 mg FCA cream was a highly significant difference in the zone of inhibition when compared to dummy cream. The 200 mg FCA was activity against Escherichia coli, methicillin-resistant Staphylococcus aureus, vancomycin-resistant E. faecium, and C. albicans highly significantly difference (p<0.05) compared FCA 50 mg and FAC 100 mg creams. Conclusion: The results from this study suggested that the cold cream form base of MECA crude had antimicrobial activity in the different clinical pathogen. They could be used as an alternative source to conventional antimicrobial agents for the treatment of pathological infection.

scholarly journals The Antimicrobial Activity of Pechuel-Loeschea leubnitziae Leaf Extract and its Effect on The Expression Level of Methicillin Resistant Staphylococcus Aureus and Candida albicans Virulence-Associated Genes

2022 ◽  
Author(s):  
Mariah Ndilimeke Muhongo ◽  
Mourine Kangogo ◽  
Christine Bii
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Candida Albicans ◽  
Leaf Extract ◽  
Target Genes ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Methanol Extract ◽  
Ethanol Extract ◽  
Expression Level ◽  
Methicillin Resistant

The complete halt in the synthesis of new effective antimicrobial compounds is a global concern. Pathogenic microorganisms' virulence mechanisms seem to have a significant impact on their pathogenesis. The purpose of this study was to examine the antimicrobial activity of the ethanol and methanol fractions of Pechuel-Loeschea leubnitziae leaf extract, as well as its effect on the expression level of virulence-associated genes.The extract's fractions were evaluated for antimicrobial activity against Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae (clinical), Methicillin-resistant Staphylococcus aureus, and Candida albicans ATCC 90029. The test organism's antibiogram pattern was determined. The extracts' attenuation effect on the target genes of the susceptible organisms was investigated employing relative quantification using RT-qPCR. The test organism's antibiogram pattern revealed that it was drug-resistant, intermediate, and sensitive. The extracts tested positive for antimicrobial activity against Methicillin-resistant Staphylococcus aureus and Candida albicans ATCC 90029, with zones of inhibition varying from 20.33 to 29 mm. The lowest recorded MIC value was 4.688 mg/ml, while the highest was 37.5 mg/ml. In contrast to the methanol extract, the ethanol extract had a cidal action at a lower dose. The ethanol extract's Sub-MIC (18.25 mg/ml) merely reduced the expression of the hly gene in MRSA. The MRSA virulence genes were not suppressed by the sub-MIC of methanol extract (18.25 mg/ml). Notably, the expression of als1, pbl1, and sap1 in Candida albicans ATCC 90029 was significantly attenuated when exposed to sub-MICs of ethanol extract (2,344 mg/ml) and methanol extract (9.375 mg/ml). Per the findings of this research, the leaves of P. leubnitziae could be a source of an effective antimicrobial agent in the therapy of MRSA/Candida-related disorders.

scholarly journals Synthesis and Antimicrobial Activities of 1-((5-Chloro-1-ethyl-2-methyl-1H-imidazol-4-yl)sulfonyl)-N-ethylpyrrolidine-2-carboxamide

2021 ◽  
Vol 47 (3) ◽  
pp. 1296-1302
Author(s):  
Oluwaseyi B. Ovonramwen ◽  
Bodunde J. Owolabi ◽  
Abiodun Falodun
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Bacillus Subtilis ◽  
Candida Albicans ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Antimicrobial Activities ◽  
Microbiological Method ◽  
Gram Negative ◽  
Methyl Imidazole

A new 1-((5-chloro-1-ethyl-2-methyl-1H-imidazol-4-yl)sulfonyl)-N-ethylpyrrolidine-2-carboxamide was synthesized from methyl-1-[(5-chloro-1-ethyl-2-methyl-1H-imidazol-4-yl)sulfonyl]pyrrolidine-2-carboxylate and ethylamine. The compound methyl-1-[(5-chloro-1-ethyl-2-methyl-1H-imidazol-4-yl)sulfonyl]pyrrolidine-2-carboxylate was synthesized from methyl pyrrolidine-2-carboxylate and 5-chloro-4-chlorosulfonyl-1-ethyl-2-methyl-imidazole. The compounds were characterized based on FTIR, 1H, 13C NMR, and DEPT 135 analysis. Antimicrobial activities of the 1-((5-chloro-1-ethyl-2-methyl-1H-imidazol-4-yl)sulfonyl)-N-ethylpyrrolidine-2-carboxamide against Gram-positive (methicillin-susceptible Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Bacillus subtilis), Gram-negative (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae), and Candida albicans were carried out using the standard microbiological method. The newly synthesized 1-((5-chloro-1-ethyl-2-methyl-1H-imidazol-4-yl)sulfonyl)-N-ethylpyrrolidine-2-carboxamide had no activities against the tested organisms. Keywords:    1-((5-chloro-1-ethyl-2-methyl-1H-imidazol-4-yl)sulfonyl)-N-ethylpyrrolidine-2-carboxamide; methyl-1-[(5-chloro-1-ethyl-2-methyl-1H-imidazol-4-yl)sulfonyl]pyrrolidine-2-carboxylate; L-proline; ethylamine.

scholarly journals A Time-Kill Assay Study on the Synergistic Bactericidal Activity of Pomegranate Rind Extract and Zn (II) against Methicillin-Resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa

Biomolecules ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1889
Author(s):  
Amal Alrashidi ◽  
Mohammed Jafar ◽  
Niamh Higgins ◽  
Ciara Mulligan ◽  
Carmine Varricchio ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Bactericidal Activity ◽  
Staphylococcus Epidermidis ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Synergistic Activity ◽  
Methicillin Resistant ◽  
Time Kill

There is a need for new antimicrobial systems due to increased global resistance to current antimicrobials. Pomegranate rind extract (PRE) and Zn (II) ions both possess a level of antimicrobial activity and work has previously shown that PRE/Zn (II) in combination possesses synergistic activity against Herpes simplex virus and Micrococcus luteus. Here, we determined whether such synergistic activity extended to other, more pathogenic, bacteria. Reference strains of methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa were cultured and subjected to challenge by PRE, Zn (II), or PRE + Zn (II), in time-kill assays. Data were obtained independently by two researchers using different PRE preparations. Statistically significant synergistic activity for PRE + Zn (II) was shown for all four bacterial strains tested compared to untreated controls, although the extent of efficacy and timescales varied. Zn (II) exerted activity and at 1 h, it was not possible to distinguish with PRE + Zn (II) combination treatment in all cases. PRE alone showed low activity against all four bacteria. Reproducible synergistic bactericidal activity involving PRE and Zn (II) has been confirmed. Potential mechanisms are discussed. The development of a therapeutic system that possesses demonstrable antimicrobial activity is supported which lends itself particularly to topical delivery applications, for example MRSA infections.

scholarly journals Synthesis, Characterization and Crystal Structures of Fluoro-Substituted Aroylhydrazones with Antimicrobial Activity

2021 ◽  
Vol 68 (3) ◽  
pp. 541-547
Author(s):  
Fu-Ming Wang ◽  
Li-Jie Li ◽  
Guo-Wei Zang ◽  
Tong-Tong Deng ◽  
Zhong-Lu You
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Bacillus Subtilis ◽  
Candida Albicans ◽  
1H Nmr Spectroscopy ◽  
Antimicrobial Activities ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diphenyl Tetrazolium Bromide

A series of five new fluoro-substituted aroylhydrazones were prepared and structurally characterized by elemental analysis, IR, UV-Vis and 1H NMR spectroscopy, as well as single crystal X-ray diffraction. The compounds were evaluated for their antibacterial (Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas fluorescence) and antifungal (Candida albicans and Aspergillus niger) activities by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) method. The biological assay indicated that the presence of the electron-withdrawing groups in the aroylhydrazones improved their antimicrobial activities.

scholarly journals Synthesis and Antimicrobial Activities of some Quaternary Morpholinium Chlorides

2010 ◽  
Vol 59 (1) ◽  
pp. 49-53 ◽  
Author(s):  
BOGUMIŁ BRYCKI ◽  
ZOFIA DEGA-SZAFRAN ◽  
ILONA MIRSKA
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Candida Albicans ◽  
Nitrogen Atom ◽  
Alkyl Group ◽  
Antimicrobial Activities ◽  
Proteus Vulgaris

The synthesis and antimicrobial activity of 31 morpholinium chlorides, divided into five series depending on the substituents attached to the nitrogen atom, N-carboxyalkyl-morpholinium chlorides (1a-e), N-carbalkoxymethyl-N-methyl-morpholinium chlorides (2a-f), N-carbethoxymethyl-N-alkyl-morpholinium chlorides (3a-g), N-carbalkoxymethyl-N-dodecyl-morpholinium chlorides (4a-f) and N-carboxymethyl-N-alkyl-morpholinium chlorides (5a-g) is reported. The compounds investigated were tested for antimicrobial activity against Staphylococcus aureus, Escherichia coli, Proteus vulgaris, Pseudomonas aeruginosa, Candida albicans and Trichophyton menthagrophytes. The most active are compounds with a long N-alkyl group and with the substituent CH2COOC(n)H(2n-1) (n = 8-16).

scholarly journals Antimicrobial Activities and Mechanism of Action of Petiveria alliacea Stem Extract

2018 ◽  
Vol 1 (1) ◽  
pp. 45-55
Author(s):  
Yani Mulyani ◽  
Ika Kurnia Sukmawati ◽  
Jajang Jafar Sodik
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Candida Albicans ◽  
Molecular Docking ◽  
Mechanism Of Action ◽  
Ethanol Extract ◽  
Antimicrobial Activities ◽  
Petiveria Alliacea

Abstract. This research aimed to determine the antimicrobial activity of ethanol extract of Petiveria alliacea stem (EEPS) against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined by perforation and broth micro dilution methods. Study on the mechanism of action of EEPS was conducted by molecular docking and Scanning Electron Microscopy (SEM) techniques. The results showed that EEPS had an inhibitory activity against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans with MIC values of 256, 128, 256, 512 µg/ml, consecutively. These values are included in to the medium category. Through the process of molecular docking, the best interaction was observed between S-benzyl-L-cysteine sulfoxide with penicillin-binding protein receptor of Pseudomonas aeruginosa characterized by free energy change (ΔG) of 4.32 kcal/mol, and the Ki value of 682.16 μM. Four folds of MIC of the EEPS caused changes in the morphology of Pseudomonas aeruginosa. EEPS possessed antimicrobial activities against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans.   Keywords: Antimicrobial Activity, Molecular Docking, Petiveria alliacea, SEM.

scholarly journals Synthesis and Antimicrobial Activity Evaluation of Some Novel Heterocycles Derived from Chromonyl-2(3H)-furanone

2018 ◽  
Vol 42 (6) ◽  
pp. 332-336 ◽  
Author(s):  
Sayed K. Ramadan ◽  
Eman A. E. El-Helw
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Candida Albicans ◽  
Spectral Data ◽  
Aspergillus Flavus ◽  
Antimicrobial Activities ◽  
Nitrogen Nucleophiles ◽  
And Staphylococcus Aureus

6-Chloro-3-((2-oxo-5-phenylfuran-3(2 H)-ylidene)methyl)-4 H-chromen-4-one was utilised for the construction of N-heterocycles. The proclivity of this furanone towards some nitrogen nucleophiles, i.e. glycine, thiosemicarbazide, thiocarbohydrazide, phenylhydrazine and o-phenylenediamine, was studied. The structures of all products obtained were established on the basis of their analytical and spectral data. All synthesised compounds were screened for their in vitro antibacterial (two strains of bacteria; Escherichia coli and Staphylococcus aureus) and antifungal (two fungus strains; Aspergillus flavus and Candida albicans) activities. Some products exhibited promising antimicrobial activities.

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