Antibiotic potential of some synthesized derivatives of C-9154 antibiotic

2020 ◽  
Vol 15 (2) ◽  
pp. 52-58
Author(s):  
Isaac Asusheyi Bello ◽  
Isaac Asusheyi Bello ◽  
George Iloegbulam Ndukwe ◽  
Joseph Olorunju Amupitan ◽  
Rachael Gbekele Ayo ◽  
...  

Structural modification of the C-9154 antibiotic in an attempt to simultaneously improve its activity and lower its toxicity led to the synthesis of an analogue of the C-9154 antibiotic and six derivatives of this analogue. The significant reduction of the polarity of the synthesized analogue in the derivatives to increase permeability across cell membranes was achieved by conversion of the highly polar carboxylic group to the nonpolar ester functional groups. The compounds were synthesized by condensation of 4-nitroaniline with maleic anhydride and then conversion of the terminal carboxylic acid functional group to an ester functional group using a thionyl chloride-mediated esterification. The in vitro biological activity using gram positive bacteria (MRSA, S. pyogenes, B. subtilis, and C. ulcerans), gram negative bacteria (E. coli, P. mirabilis, P. aeruginosa, S. typhii, S. dysenteriae, and K. pneumonia and some fungi (C. albicans, A. nigre and T. rubrum), showed that the derivatives were more active than their respective analogue and significantly better than the standard antibiotics (Sparfloxacin and Fluconazole) used for comparison, establishing their potential or use as antibiotics. The derivatives exhibited activity at concentrations as low as 0.625μg/mL while the analogue was active at 2.5μg/mL. These values were higher than results obtained for the standard drugs which showed activity at concentrations of 5 μg/mL. The derivatives however did not show activity against A. nigre whereas the analogue was active against it. Keywords: C-9154 Antibiotic, Bioactivity, Fumaramidmycin, antibacterial, antifungal

2020 ◽  
Vol 840 ◽  
pp. 265-269
Author(s):  
Nurjanah Nurjanah ◽  
Endang Saepudin

Curcumin, a diarylheptanoids compound which isolated primary from Curcuma longa, exhibits a variety of exciting biological activities, including as an antibacterial agent. In the present study, a sulfanilamide-contained curcumin compound was synthesized and characterized to investigate the antibacterial activity against gram-positive bacteria S. aureus, B. subtilis and gram-negative bacteria E. coli. The characterization of the synthesized compound was determined by analysing peak absorbance, functional group, and molecular weight using mass spectroscopy, UV/Vis and FTIR spectrophotometry. Curcumin-sulfanilamide compound exhibited the best antibacterial activity against gram-negative bacteria compared to curcumin and the curcumin-derived compound containing isoxazole with inhibitory zone of 11 mm.


Author(s):  
Chinyere Benardette Chinaka Ikpa ◽  
Uchechukwu C. Okoro ◽  
Collins I. Ubochi ◽  
Kieran O. Nwanorh

The 2-phenylsulphonamide derivatives of amino acids were synthesis by simple substitution of benzenesulphonylchloride (6) with amino acids (1-5) containing pharmacological active functionalities. Structures of the synthesised compounds (7a-7e) were characterised using FT-IR, NMR(1H,13C) and elemental analysis. The anti bacterial activities of the synthesised compounds were evaluated against gram positive bacteria: Staph and Streptococcus, gram negative bacteria: E-coli, Klebsiella, Proteus, and pseudomonas using 200 µl of 10 mg/ml and minimum inhibitory concentration (MIC) were also determined. The compounds exhibited effective anti bacterial properties though some are not more active than the standard drug ciprofloxacin.


2012 ◽  
Vol 2012 ◽  
pp. 1-7
Author(s):  
Isaac Asusheyi Bello ◽  
George Iloegbulam Ndukwe ◽  
Joseph Olorunju Amupitan ◽  
Rachael Gbekele Ayo ◽  
Francis Oluwole Shode

This research was undertaken to design several new antibiotics, by structurally modifying the C-9154 antibiotic, simultaneously improving its activity and lowering toxicity. This was achieved by synthesizing an analogue to the C-9154 antibiotic and seven derivatives of this analogue. The approach was to significantly reduce the polarity of the synthesized analogue in the derivatives to achieve increased permeability across cell membranes by conversion of the highly polar carboxylic group to an ester functional group. The compounds were fully characterized using infrared, GC-MS, and 1D and 2D NMR experiments. The in vitro biological activity of the compounds showed that the derivatives were more active than the analogue as was anticipated and both were more active than the standard drugs used for comparison. Work is ongoing to establish applications for the compounds as antiplasmodials, antivirals, anticancers/tumours, antitrypanosomiasis, anthelminthic, and as general antibiotics for human, veterinary, and even agricultural use as they had marked effect on both Gram-positive and Gram-negative bacteria and some fungi.


2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Angela Filocamo ◽  
Carlo Bisignano ◽  
Giuseppina Mandalari ◽  
Michele Navarra

Background. The aim of the present study was to evaluate the antimicrobial effect of a white grape juice extract (WGJe) against a range of Gram-positive and Gram-negative bacteria, yeasts, and the fungusAspergillus niger. WGJe was also tested on the production of bacterial biofilmsin vitro.Results. WGJe inhibitedin vitromost Gram-positive bacteria tested,Staphylococcus aureusATCC 6538P being the most sensitive strain (MIC values of 3.9 μg/mL). The effect was bactericidal at the concentration of 500 μg/mL. Amongst the Gram-negative bacteria,Escherichia coliwas the only susceptible strain (MIC and MBC of 2000 μg/mL). No effect on the growth ofCandidasp. and the fungusAspergillus nigerwas detected (MIC values > 2000 μg/mL). WGJe inhibited the biofilms formation ofE. coliandPseudomonas aeruginosawith a dose-dependent effect.Conclusions. WGJe exerted both bacteriostatic and bactericidal activityin vitro. The presented results could be used to develop novel strategies for the treatment of skin infections and against potential respiratory pathogens.


2020 ◽  
Vol 16 (4) ◽  
pp. 481-488
Author(s):  
Heli Sanghvi ◽  
Satyendra Mishra

Background: Curcumin, one of the most important pharmacologically significant natural products, has gained significant consideration among scientists for decades since its multipharmacological activities. 1, 3-Dicarbonyl moiety of curcumin was found to be accountable for the rapid degradation of curcumin molecule. The aim of present work is to replace 1, 3-dicarbonyl moiety of curcumin by pyrazole and phenylpyrazole derivatives with a view to improving its stability and to investigate the role of substitution in N-phenylpyrazole curcumin on its antibacterial activity against both Gram-positive as well as Gram-negative bacteria. Methods: Pyrazole derivatives of curcumin were prepared by heating curcumin with phenyhydrazine/ substituted phenyhydrazine derivatives in AcOH. The residue was purified by silica gel column chromatography. Structures of purified compounds were confirmed by 1H NMR and Mass spectroscopy. The synthesized compounds were evaluated for their antibacterial activity by the microdilution broth susceptibility test method against gram positive (S. aureus) and gram negative (E. coli). Results: Effects of substitution in N-phenylpyrazole curcumin derivatives against S. aureus and E. coli were studied. The most active N-(3-Nitrophenylpyrazole) curcumin (12) exhibits twenty-fold more potency against S. aureus (MIC: 10μg/mL)) and N-(2-Fluoroophenylpyrazole) curcumin (5) fivefold more potency against E. coli (MIC; 50 μg/mL) than N-phenylpyrazole curcumin (4). Whereas, a remarkable decline in anti-bacterial activity against S. aureus and E. coli was observed when electron donating groups were incorporated in N-phenylpyrazole curcumin (4). Comparative studies of synthesized compounds suggest the effects of electron withdrawing and electron donating groups on unsubstituted phenylpyrazole curcumin (4). Conclusion: The structure-activity relationship (SAR) results indicated that the electron withdrawing and electron donating at N-phenylpyrazole curcumin played key roles for their bacterial inhibitory effects. The results of the antibacterial evaluation showed that the synthesized pyrazole derivatives of curcumin displayed moderate to very high activity in S. aureus. In conclusion, the series of novel curcumin derivatives were designed, synthesized and tested for their antibacterial activities against S. aureus and E. coli. Among them, N-(3-Nitrophenylpyrazole curcumin; 12) was most active against S. aureus (Gram-positive) and N-(2-Fluoroophenylpyrazole) curcumin (5) against E. coli (Gram-negative) bacteria.


2006 ◽  
Vol 50 (6) ◽  
pp. 2261-2264 ◽  
Author(s):  
Hee-Soo Park ◽  
Hyun-Joo Kim ◽  
Min-Jung Seol ◽  
Dong-Rack Choi ◽  
Eung-Chil Choi ◽  
...  

ABSTRACT DW-224a showed the most potent in vitro activity among the quinolone compounds tested against clinical isolates of gram-positive bacteria. Against gram-negative bacteria, DW-224a was slightly less active than the other fluoroquinolones. The in vivo activities of DW-224a against gram-positive bacteria were more potent than those of other quinolones.


2006 ◽  
Vol 50 (7) ◽  
pp. 2478-2486 ◽  
Author(s):  
Andrea Giacometti ◽  
Oscar Cirioni ◽  
Roberto Ghiselli ◽  
Federico Mocchegiani ◽  
Fiorenza Orlando ◽  
...  

ABSTRACT Sepsis remains a major cause of morbidity and mortality in hospitalized patients, despite intense efforts to improve survival. The primary lead for septic shock results from activation of host effector cells by endotoxin, the lipopolysaccharide (LPS) associated with cell membranes of gram-negative bacteria. For these reasons, the quest for compounds with antiendotoxin properties is actively pursued. We investigated the efficacy of the amphibian skin antimicrobial peptide temporin L in binding Escherichia coli LPS in vitro and counteracting its effects in vivo. Temporin L strongly bound to purified E. coli LPS and lipid A in vitro, as proven by fluorescent displacement assay, and readily penetrated into E. coli LPS monolayers. Furthermore, the killing activity of temporin L against E. coli was progressively inhibited by increasing concentrations of LPS added to the medium, further confirming the peptide's affinity for endotoxin. Antimicrobial assays showed that temporin L interacted synergistically with the clinically used β-lactam antibiotics piperacillin and imipenem. Therefore, we characterized the activity of temporin L when combined with imipenem and piperacillin in the prevention of lethality in two rat models of septic shock, measuring bacterial growth in blood and intra-abdominal fluid, endotoxin and tumor necrosis factor alpha (TNF-α) concentrations in plasma, and lethality. With respect to controls and single-drug treatments, the simultaneous administration of temporin L and β-lactams produced the highest antimicrobial activities and the strongest reduction in plasma endotoxin and TNF-α levels, resulting in the highest survival rates.


2020 ◽  
Vol 7 (8) ◽  
pp. 1290
Author(s):  
Saswat Subhankar ◽  
K. Madhuri ◽  
Vivek D. Alone

Osteomyelitis is an infection of the bones caused by pyogenic organisms. The ribs are an extremely uncommon site for osteomyelitis, occurring in less than 1% cases. The main causative organisms are Gram-positive bacteria, such as Staphylococcus aureus and Hemophilus influenzae. Gram-negative bacteria like E. coli have been rarely reported. Authors hereby present a case of an immune-competent patient who presented with an osteomyelitis of the ribs caused by the latter. In developing countries, tuberculosis is considered as the primary cause of osteomyelitis and pleural effusions. However, other organisms should also be considered in patients who present with fulminant infections.


1996 ◽  
Vol 34 (10) ◽  
pp. 89-95 ◽  
Author(s):  
Hu Tai-Lee

The use of biomass for the removal of reactive dyes from an aqueous solution with different bacterial genera has been investigated. Three Gram-negative bacteria: Aeromonas sp., P. luteola and E. coli, and two Gram-positive bacteria: B. subtilis and S. aureus and a mixed biomass of activated sludge are the tested biosorbents. Dead cells of Gram-negative bacteria have a higher specific adsorption capacity than the living cells. The dye removal is in the order of Aeromonoas sp. > P. luteola > E. coli. The adsorption equilibrium can be reached within one hour. Due to the positively charged cells at acidic pH, the removal of reactive dyes increases with decreasing pH. Evaluating the adsorption parameters, bacterial biomass exhibits stable adsorption characteristics, which makes it a suitable adsorbent for different dye compounds.


2019 ◽  
Vol 18 (5) ◽  
pp. 1147-1155 ◽  
Author(s):  
Rehan Khan ◽  
Melis Özkan ◽  
Aisan Khaligh ◽  
Dönüs Tuncel

Water-dispersible glycosylated poly(2,5′-thienylene)porphyrin-based nanoparticles have the ability to generate singlet oxygen in high yields and exhibit light-triggered antibacterial activity against Gram negative bacteria, E. coli as well as Gram positive bacteria, B. subtilis.


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