Posted by admin on Sep 1, 2011 in |
There has been considerable interest in the development of novel compounds with anticonvulsant, antidepressant, analgesic, anti-inflammatory, anti platelet, anti malarial, antimicrobial, antimycobacterial, antitumoral, vasodilator, antiviral and antis chistosomiasis activities. Hydrazones possessing an azometine -NHN=CH- proton constitute an important class of compounds for new drug development. Therefore, many researchers have synthesized these compounds as target structures and evaluated their biological activities. These observations have been guiding for the development of new hydrazones that possess varied biological activities....
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Posted by admin on Sep 1, 2011 in |
Preservatives are added to pharmaceuticals to ensure safety and shelf life. A number of Essential oil components are identified as effective antimicrobials. The antimicrobial activity is assessed of pure oils. Oils were evaluated based on Refractive index, Specific gravity and Antimicrobial activity. In present study Syrups were prepared using Peppermint, Rose and Orange oils in different concentrations and antimicrobial activity was determined by using same syrups and compared with antimicrobial activity of pure oils determined by using same concentrations as used in syrups at the end of 7, 14 and 28 days. It was found that pure oils showed higher activity than syrups and only peppermint oil used in concentration of 2% showed antimicrobial activity after 28 days against S. aureus. Syrups containing Rose oil showed activity against E. coli in concentrations of 1% and 2%, against S. aureus only 2% syrup showed activity. All oils were found to be more active against Gram +ve microorganisms than Gram –ve...
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Posted by admin on Jul 1, 2011 in |
Methanol extract of leaves of Spilanthes calva (DC) was examined for their antimicrobial and cytotoxic properties. To determine antibacterial activities, the extract was tested against four gram-positive and six gram-negative bacteria at three concentrations (500, 800, 1000 µg disc-1) through disc diffusion method. The extract showed moderate antibacterial actions and that was increased by increasing the concentration of the sample. The maximum antimicrobial potential was obtained against Staphylococcus aureus and no sensitivity was found for Escherichia coli. Comparatively gram-positive bacteria demonstrated more susceptibility to the extract than gram-negative bacteria. Cytotoxic property of the sample was done using Brine shrimp lethality bioassay where it did not show noticeable toxicity. So, our present study reveals that the leaves extract of S. calva possess considerable antibacterial properties along with lesser amount of...
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Posted by admin on Jul 1, 2011 in |
Antibacterial, antifungal and phytotoxic activities of the prepared pyrazine derivatives of benzil (A), 4, 4’-dibromobenzil (B) and α-diketones of triterpenoids skeleton e.g. 2, 3-diketolupene (C) and 2, 3-diketomethyl- dihydrobetulonate (D) were studied. The prepared 1, 4-pyrazine derivatives (E, F, G & H respectively) have been characterized by UV, IR, NMR (1H and 13C), optical rotation, mass spectra and by comparison with authentic samples. Disc diffusion technique was used to determine in vitro antibacterial and antifungal activities. Phytotoxicity was determined against seed growth technique. In addition, minimum inhibitory concentration (MIC) was determined using serial dilution technique to determine antibacterial potency. The derivatives showed significant antimicrobial activities against Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa (bacterial specimen), Colletotrichum camelliae, Fusarium equisiti, Alternaria alternata, Curvularia eragrostidis and Colletotrichum gloeosporioides (fungal...
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Posted by admin on Jul 1, 2011 in |
The aim of this study was to determine the antimicrobial activity of three selected Lebanese plants (Rheum rhaponticum, Olea europaea, and Viola Odorata) against Extended Spectrum Beta Lactamase (ESBL) – producing Escherichia coli and Klebsiella pneumoniae, and to identify the specific plant fraction responsible for the antimicrobial activity. The plants were extracted with ethanol to yield the crude extract which was further subfractionated by different solvents to obtain the petroleum ether, the dichloromethane, the ethyl acetate and the aqueous fractions. The Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentrations (MBC) were determined using broth microdilution. The MICs ranged between 2.5 and 80 μg/μl. The majority of these microorganisms were inhibited by 80 and 40 μg/μl of the crude extracts. The dichloromethane fraction of Olea europea exerted a significant inhibitory effect on 90% of the tested strains. Ethyl acetate extracts of all selected plants presented antibacterial activity with high potency. Aqueous extracts of Rheum rhaponticum and Olea europaea exerted antimicrobial activity against the majority of the tested strains while Viola...
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