scholarly journals Antibacterial activity of cobalt(II) complexes with some benzimidazole derivatives

2008 ◽  
Vol 73 (12) ◽  
pp. 1153-1160 ◽  
Author(s):  
S.O. Podunavac-Kuzmanovic ◽  
V.M. Leovac ◽  
D.D. Cvetkovic
Keyword(s):  
Antibacterial Activity ◽  
Chemical Structure ◽  
Antibacterial Activities ◽  
Benzimidazole Derivatives ◽  
Wall Structure ◽  
Gram Negative Bacteria ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative

The antibacterial activities of cobalt(II) complexes with two series of benzimidazoles were evaluated in vitro against three Gram-positive bacterial strains (Bacillus cereus, Staphylococcus aureus, and Sarcina lutea) and one Gram-negative isolate (Pseudomonas aeruginosa). The minimum inhibitory concentration was determined for all the complexes. The majority of the investtigated complexes displayed in vitro inhibitory activity against very persistent bacteria. They were found to be more active against Gram-positive than Gram-negative bacteria. It may be concluded that the antibacterial activity of the compounds is related to the cell wall structure of the tested bacteria. Comparing the inhibitory activities of the tested complexes, it was found that the 1-substituted- -2-aminobenzimidazole derivatives were more active than complexes of 1-substituted- 2-amino-5,6-dimethylbenzimidazoles. The effect of chemical structure on the antibacterial activity is discussed.

scholarly journals In Vitro and In Vivo Antibacterial Activities of DW-224a, a New Fluoronaphthyridone

2006 ◽  
Vol 50 (6) ◽  
pp. 2261-2264 ◽  
Author(s):  
Hee-Soo Park ◽  
Hyun-Joo Kim ◽  
Min-Jung Seol ◽  
Dong-Rack Choi ◽  
Eung-Chil Choi ◽  
...  
Keyword(s):  
Antibacterial Activities ◽  
The Other ◽  
Vitro Activity ◽  
Gram Negative Bacteria ◽  
In Vitro Activity ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria

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.

scholarly journals Antibacterial Potential of Aloe weloensis (Aloeacea) Leaf Latex against Gram-Positive and Gram-Negative Bacteria Strains

2019 ◽  
Vol 2019 ◽  
pp. 1-4
Author(s):  
Yohannes Kelifa Emiru ◽  
Ebrahim Abdela Siraj ◽  
Tekleab Teka Teklehaimanot ◽  
Gedefaw Getnet Amare
Keyword(s):  
Antibacterial Activity ◽  
Bacterial Infections ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Maximum Activity ◽  
New Drugs ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative

Objective. To evaluate the antibacterial effects of the leaf latex of Aloe weloensis against infectious bacterial strains. Methods. The leaf latex of A. weloensis at different concentrations (400, 500, and 600 mg/ml) was evaluated for antibacterial activities using the disc diffusion method against some Gram-negative species such as Escherichia coli (ATCC 14700) and Pseudomonas aeruginosa (ATCC 35619) and Gram-positive such as Staphylococcus aureus (ATCC 50080) and Enterococcus fecalis (ATCC 4623). Results. The tested concentrations of the latex ranging between 400 and 600 mg·mL−1 showed significant antibacterial activity against bacterial strain. The highest dose (600 mg/ml) of A. weloensis leaf latex revealed the maximum activity (25.93 ± 0.066 inhibition zone) followed by the dose 500 mg/ml against S. aureus. The lowest antibacterial activity was observed by the concentration 400 mg/ml (5.03 ± 0.03) against E. coli. Conclusion. The results of the present investigation suggest that the leaf latex of A. weloensis can be used as potential leads to discover new drugs to control some bacterial infections.

Antibacterial Activity and Chemical Composition of the Essential Oil of Grammosciadium platycarpum Boiss. from Iran

2005 ◽  
Vol 60 (1-2) ◽  
pp. 30-34 ◽  
Author(s):  
Ali Sonboli ◽  
Fereshteh Eftekhar ◽  
Morteza Yousefzadi ◽  
Mohammad Reza Kanani
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Chemical Composition ◽  
Essential Oil ◽  
Essential Oils ◽  
Antibacterial Activities ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Two Samples

The chemical composition of the essential oils obtained from two samples (GP1 and GP2) of Grammosciadium platycarpum Boiss. was analyzed by GC and GC-MS. The analysis of the oils resulted in the identification of twenty-two constituents. Linalool (79.0% - GP1, 81.8% - GP2) and limonene (10.0%, 5.8%) were found to be the major components, respectively. The in vitro antibacterial activities of these oils and their main compounds against seven Gram-positive and Gram-negative bacteria were investigated. The results exhibited that the total oils and their major components possess strong to moderate activities against all the tested bacteria except for Pseudomonas aeruginosa.

scholarly journals Evaluation of antibacterial activity of vitamin C against human bacterial pathogens

2023 ◽  
Vol 83 ◽  
Author(s):  
S. Mumtaz ◽  
S. Mumtaz ◽  
S. Ali ◽  
H. M. Tahir ◽  
S. A. R. Kazmi ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Vitamin C ◽  
Bacterial Infections ◽  
Unmet Need ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Bacterial Strains ◽  
Gram Positive ◽  
Gram Negative ◽  
Adjunct Treatment

Abstract Now a day’s multidrug resistance phenomenon has become the main cause for concern and there has been an inadequate achievement in the development of novel antibiotics to treat the bacterial infections. Therefore, there is an unmet need to search for novel adjuvant. Vitamin C is one such promising adjuvant. The present study was aimed to elucidate the antibacterial effect of vitamin C at various temperatures (4°C, 37°C and 50°C) and pH (3, 8, and 11), against Gram-positive and Gram-negative bacteria at various concentrations (5-20 mg/ml) through agar well diffusion method. Growth inhibition of all bacterial strains by vitamin C was concentration-dependent. Vitamin C significantly inhibited the growth of Gram-positive bacteria: Bacillus licheniformis (25.3 ± 0.9 mm), Staphylococcus aureus (22.0 ± 0.6 mm), Bacillus subtilis (19.3 ± 0.3 mm) and Gram-negative bacteria: Proteus mirabilis (27.67 ± 0.882 mm), Klebsiella pneumoniae (21.33±0.9 mm), Pseudomonas aeruginosa (18.0 ± 1.5 mm) and Escherichia coli (18.3 ± 0.3 mm). The stability of vitamin C was observed at various pH values and various temperatures. Vitamin C showed significant antibacterial activity at acidic pH against all bacterial strains. Vitamin C remained the stable at different temperatures. It was concluded that vitamin C is an effective and safe antibacterial agent that can be used in the future as an adjunct treatment option to combat infections in humans.

In Vitro Antibacterial Activities and Mechanisms of Action of Fatty Acid Monoglycerides Against Four Foodborne Bacteria

2020 ◽  
Vol 83 (2) ◽  
pp. 331-337
Author(s):  
WENYUE WANG ◽  
RUI WANG ◽  
GUIJU ZHANG ◽  
FANGLI CHEN ◽  
BAOCAI XU
Keyword(s):  
Antibacterial Activity ◽  
Antibacterial Activities ◽  
Carbon Chain ◽  
Antimicrobial Activities ◽  
Inhibitory Effect ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Alkaline Conditions

ABSTRACT Naturally occurring monoglyceride esters of fatty acids have been associated with a broad spectrum of antimicrobial activities. We used an automated turbidimetric method to measure the MIC and assess the antimicrobial activity of five monoglycerides (monocaprin, monolaurin, monomyristin, monopalmitin, and monostearin) against pathogenic strains of Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli. The antibacterial activity of monocaprin was highest because its carbon chain is shorter than those of other monoglycerides. The MICs of monocaprin against S. aureus, B. subtilis, P. aeruginosa, and E. coli were 0.32, 0.32, 2.5, and 2.5 mg/mL, respectively. Monocaprin had antibacterial activity under neutral and alkaline conditions (pH 7.0 to 9.0) but had no inhibitory effect on S. aureus, B. subtilis, and E. coli under weakly acidic conditions (pH 6.0). The antibacterial mechanism of monocaprin against gram-positive strains (S. aureus and B. subtilis) resulted from destruction of the cell membrane. In contrast, the antibacterial activity of monocaprin against gram-negative strains (P. aeruginosa and E. coli) was attributed to damage to lipopolysaccharides in the cell walls. Because of its inhibitory effect on both gram-positive and gram-negative bacteria, monocaprin could be used as an antibacterial additive in the food industry. HIGHLIGHTS

The Effects of Natural Dopant Acids on Morphologies and Antibacterial Activity of Polyaniline

2013 ◽  
Vol 650 ◽  
pp. 249-252 ◽  
Author(s):  
Jia Li Mu ◽  
Wen Jun Fan ◽  
Shao Yun Shan ◽  
Ting Wei Hu ◽  
Ya Ming Wang ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Salicylic Acid ◽  
Citric Acid ◽  
Rosin Acid ◽  
Antibacterial Activities ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Bacillus Coli

Polyaniline(PANI) doped by natural acid(citric acid, salicylic acid or rosin acid)solutions was synthesized using aniline as monomer and ammonium peroxydisulfate ((NH4)2S2O8) as oxidant. The antibacterial activities of the PANI against Gram positive bacteria(Bacillus megatherium, Bacillus subtilis, Bacillus cereus and Staphylo-coccus aureus) and Gram negative bacteria(Bacillus coli) were investigated. It was shown that PANI doped by citric acid possessed the better antibacterial activity against the selected species of Gram positive bacteria and Gram negative bacteria than PANI doped by rosin acid. PANI doped by salicylic acid exhibited ascendant antibacterial activities against Gram positive bacteria, but it has little antibacterial activity against the Gram negative bacteria.

scholarly journals Synthesis and Pharmacological Evaluation of Some New 2-Phenyl benzimidazoles Derivatives and their Schiff's Bases

2009 ◽  
Vol 6 (s1) ◽  
pp. S342-S346 ◽  
Author(s):  
Y. S. Chhonker ◽  
B. Veenu ◽  
S. R. Hasim ◽  
Niranjan Kaushik ◽  
Devendra Kumar ◽  
...  
Keyword(s):  
Antimicrobial Activities ◽  
Benzimidazole Derivatives ◽  
Spectroscopic Techniques ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
H Nmr ◽  
Ir Spectroscopic

Some new 2- phenyl benzimidazole derivatives were synthesised by cyclocondensation with appropriate reagents. The compounds synthesised were identified by1H NMR, FAB Mass and FT-IR spectroscopic techniques. All compounds studied in this work were screened for theirin vitroantimicrobial activities against the standard strains:Staphylococcus aureusATCC - 25923, ATCC - 441 andBacillus subtilisATCC- 6633 as gram positive,Escherichia coliATCC - 11775 andPseudomonas aeruginosaATCC 10145 as gram negative bacteria. Some of the compounds inhibited the growth of gram-positive bacteria (B. subtilisandS. aureus) at MIC values between 25 and 200 mg/mL. Some of the compounds exhibit antimicrobial activity against gram negative bacteria (E. coliandP. Aeruginosa) MIC values between 25 and 200 mg/mL.

In vitro Antibacterial Activity of 7-Substituted-6-Fluoroquinolone and 7-Substituted-6,8-Difluoroquinolone Derivatives

Chemotherapy ◽  
2017 ◽  
Vol 62 (3) ◽  
pp. 194-198 ◽  
Author(s):  
Socorro Leyva-Ramos ◽  
Denisse de Loera ◽  
Jaime Cardoso-Ortiz
Keyword(s):  
Antibacterial Activity ◽  
Antimicrobial Agents ◽  
New Drugs ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Topoisomerase Iv ◽  
Gram Positive ◽  
Disk Diffusion Method ◽  
Gram Negative

Background: Fluoroquinolones are widely prescribed synthetic antimicrobial agents. Quinolones act by converting their targets, gyrase and topoisomerase IV, into toxic enzymes that fragment the bacterial chromosome; the irreversible DNA damage eventually causes the killing of bacteria. Thorough knowledge of the structure-activity relationship of quinolones is essential for the development of new drugs with improved activity against resistant strains. Methods: The compounds were screened for their antibacterial activity against 4 representing strains using the Kirby-Bauer disk diffusion method. Minimal inhibitory concentration (MIC) was determined by measuring the diameter of the inhibition zone using concentrations between 250 and 0.004 μg/mL. Results: MIC of derivatives 2, 3, and 4 showed potent antimicrobial activity against gram-positive and gram-negative bacteria. The effective concentrations were 0.860 μg/mL or lower. MIC for compounds 5-11 were between 120 and 515 μg/mL against Escherichia coli and Staphylococcus aureus, and substituted hydrazinoquinolones 7-10 showed poor antibacterial activity against gram-positive and gram-negative bacteria compared with other quinolones. Conclusion: Compounds obtained by modifications on C-7 of norfloxacin with the acetylated piperazinyl, halogen atoms, and substituted hydrazinyl showed good in vitro activity - some even better than the original compound.

Sign in / Sign up

Export Citation Format

Share Document