scholarly journals Biocidal activity of chicken defensin-9 against microbial pathogens

2016 ◽  
Vol 94 (2) ◽  
pp. 176-187 ◽  
Author(s):  
Haitham A. Yacoub ◽  
Salem M. El-Hamidy ◽  
Maged M. Mahmoud ◽  
Mohamed Nabih Baeshen ◽  
Hussein A. Almehdar ◽  
...  

In this study we identified the expression patterns of β-defensin-9 in chickens from Saudi Arabia, evaluated the antimicrobial activities of synthetic chicken β-defensin-9 (sAvBD-9) against pathogenic bacteria and fungi, and investigated the mode of action of sAvBD-9 on bacterial cells. The AvBD-9 gene of Saudi chickens encodes a polypeptide of 67 amino acids, which is highly similar to the polypeptide in duck, quail, and goose (97%, 86%, and 87%, respectively) and shares a low sequence similarity with the mammalian defensins. AvBD-9 is expressed in various organs and tissues of Saudi chickens and inhibits the growth of both Gram-negative and Gram-positive bacteria, as well as showing activity against unicellular and multicellular fungi (Aspergillus flavus, A. niger, and Candida albicans). sAvBD-9 completely inhibited the growth of both Gram-positive and Gram-negative bacterial strains as well as Candida albicans. The haemolytic effects of sAvBD-9 were limited. Morphological analysis by TEM revealed that sAvBD-9 induces shortening and swelling of Staphylococcus aureus and Shigella sonni cells, opens holes and deep craters in their envelopes, and leads to the release of their cytoplasmic content. Our data shed light on the potential applications of sAvBD-9 in the pharmaceutical industry.

2010 ◽  
Vol 5 (9) ◽  
pp. 1934578X1000500 ◽  
Author(s):  
Erich Schmidt ◽  
Stefanie Bail ◽  
Susanne Mirjam Friedl ◽  
Leopold Jirovetz ◽  
Gerhard Buchbauer ◽  
...  

Commercially available aroma samples were evaluated for their olfactory quality by professional perfumers and tested for their antimicrobial activity. Agar diffusion and agar-dilution were used as test methods and a set of two Gram-positive ( Staphylococcus Aureus and Enterococcus faecalis) and four Gram-negative bacterial strains ( Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris G, Klebsiella pneumoniae and Salmonella abony) and a yeast, Candida albicans, were the test microorganisms. All the investigated compounds were active against Gram-positive bacteria, especially β-caryophyllene against Enterococcus faecalis (MIC 6 ppm), but only few substances showed activity towards Gram-negative bacteria, except for cinnamic acid, which was active against all (MIC 60 ppm) and Candida albicans, against which cinnamic acid and caryophyllene oxide showed high activity (MIC < 60 ppm).


2014 ◽  
Vol 8 (3) ◽  
pp. 40-45
Author(s):  
Zina Hashem Shehab ◽  
Huda Suhail Abid ◽  
Sumaya Fadhil Hamad ◽  
Sara Haitham

The study was conducted to evaluate the inhibitory activity of methanol extract of Gardenia jasminoides leaves compared with leaf crude extracts for some organic solvents namely Methanol, Ethanol, Petroleum ether, Asetone and Chloroform on growth of some pathogenic bacteria and yeast, which included four gram positive isolates Staphylococcus aureus, Enterococcus faecalis, Streptococcus pyogenes and Bacillus cereus and gram negative isolates Escherichia coli, Salmonella typhi, Proteus vulgaris and Pseudomonas aeruginosa and some yeasts Candida albicans and Saccharomyces boulardii, by using well diffusion method. The inhibitory activity of extracts in the tested bacterial strains and yeasts was varied according to the type of extracting solvents and are tested microorganisms. The methanol callus extract which grown on Murashige and Skoog (MS) media by using (Naphthalen acitic acid) NAA and (Benzyle adenine) BA as growth regulator highly effective as compared to the other extracts as for inhibition of three gram positive bacteria and three gram negative bacteria,which include Staphylococcus aureus and, Proteus vulgaris, followed by acetone and ethanolic extracts which include two gram positive bacteria and two gram negative bacteria. All extracts had highly effect in growth of Candida albicans while all crude extracts didn’t show any sensitivity against Saccharomyces boulardii, and when we’d done (High Performance Liquid Chromatography) HPLC test for detection of some active compound we found Quinic acid, Iridiods glycosides and Crocin which its rate in fresh callus was higher than fresh leaves.


Viruses ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 192 ◽  
Author(s):  
Feng Wang ◽  
Xinyu Ji ◽  
Qiupeng Li ◽  
Guanling Zhang ◽  
Jiani Peng ◽  
...  

New strategies against antibiotic-resistant bacterial pathogens are urgently needed but are not within reach. Here, we present in vitro and in vivo antimicrobial activity of TSPphg, a novel phage lysin identified from extremophilic Thermus phage TSP4 by sequencing its whole genome. By breaking down the bacterial cells, TSPphg is able to cause bacteria destruction and has shown bactericidal activity against both Gram-negative and Gram-positive pathogenic bacteria, especially antibiotic-resistant strains of Klebsiella pneumoniae, in which the complete elimination and highest reduction in bacterial counts by greater than 6 logs were observed upon 50 μg/mL TSPphg treatment at 37 °C for 1 h. A murine skin infection model further confirmed the in vivo efficacy of TSPphg in removing a highly dangerous and multidrug-resistant Staphylococcus aureus from skin damage and in accelerating wound closure. Together, our findings may offer a therapeutic alternative to help fight bacterial infections in the current age of mounting antibiotic resistance, and to shed light on bacteriophage-based strategies to develop novel anti-infectives.


2016 ◽  
Vol 34 (2) ◽  
pp. 35
Author(s):  
Prayna P. P. Maharaj ◽  
Riteshma Devi ◽  
Surendra Prasad

Fiji is highly populated with plants containing essential oils (EO). The essential oils extracted from the leaves of the selected Fijian leafy plants were screened against two Gram-negative bacteria (Salmonella typhimurium, Pseudomonas aeruginosa) and three Gram-positive bacteria (Staphylococcus aureus, Enterococcus faecalis and Bacillus subtilis). The agar diffusion method was used to examine the antimicrobial activities of the extracted EO. All the EO tested showed antibacterial properties against one or more strains while none of the EO was active against Pseudomonas aeruginosa. Viburnum lantana (Wayfaring tree), Annona muricata (Soursop), Coleus amboinicus (Spanish thyme) and Cinnamomum zeylancium (Cinnamon) showed good inhibition against both Gram-positive and Gram-negative bacteria and proved as worthy source of antimicrobial agent. These findings will help the Pacific population to use the studied plants leaves as antimicrobial agent.


2004 ◽  
Vol 59 (5-6) ◽  
pp. 373-378 ◽  
Author(s):  
El-Sayed S. Mansour ◽  
Galal T. Maatooq ◽  
Ashraf T. Khalil ◽  
El-Sayed M. Marwan ◽  
Amal A. Sallam

The composition of the essential oil of the fruits, leaves and stems of Daucus glaber Forssk has been studied by GC/MS. It was found that, the essential oil of the fruits consists of monoterpene hydrocarbons (limonene and sylvestrene are the majors) and phenylpropanoids (elemicin is the major). Sylvestrene has never been reported before in the essential oil of any Daucus species. The study of the essential oil of the leaves revealed the presence of monoterpene hydrocarbons; limonene and γ-terpinene are the majors and a small amount of sylvestrene. The essential oil of stems consists of monoterpene hydrocarbons (γ-terpinene is the major), terpene alcohols (mainly 4-terpineol) and phenylpropanoids (myristicin and elemicin are the majors). It is interesting that, the essential oil of the fruits is free from any oxygenated terpenes while that of the stems is free from limonene and sylvestrene which are present in the essential oil of the fruits and leaves in fairly large amounts. The essential oil of the fruits, leaves and stems shows broad antimicrobial activities against both gram positive and gram negative bacteria. In addition, the volatile oil of the stem, particularly, show activi­ties against Candida albicans (yeast). Also, the prepared oils have variable cytotoxic activities with LC50 21.52, 36.01 and 42.34 μrg/ml. respectively.


2007 ◽  
Vol 2 (4) ◽  
pp. 1934578X0700200 ◽  
Author(s):  
Leopold Jirovetz ◽  
Gerhard Buchbauer ◽  
Thomas Schweiger ◽  
Zapriana Denkova ◽  
Alexander Slavchev ◽  
...  

The chemical composition of a sample of Jasminum grandiflorum L. absolute from India was analyzed by GC and GC/MS. The major compounds identified were benzyl acetate (23.7%), benzyl benzoate (20.7%), phytol (10.9%), linalool (8.2%), isophytol (5.5%), geranyl linalool (3.0%), methyl linoleate (2.8%) and eugenol (2.5%). The odor of this absolute sample was olfactorically evaluated as intense and heavy floral-flowery, with penetrant-animalic and fruity side-notes. Some main and minor compounds were found to be responsible for the aroma impression of this sample. The antimicrobial activities of the J. grandiflorum sample and of some of its main and minor compounds were tested against Gram-positive and Gram-negative bacteria, as well as against the yeast Candida albicans, using agar dilution and agar diffusion methods. The jasmine absolute showed medium to high activity (reference compounds: eugenol and three synthetic antibiotics) against the Gram-positive bacterium Enterococcus faecalis, against the Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Salmonella sp., as well as against the yeast Candida albicans. A comparison of these biological data with those of some constituents of the jasmine absolute is also given.


2020 ◽  
Vol 17 ◽  
Author(s):  
Srinu Bhoomandla ◽  
Phani Raja Kanuparthy ◽  
Rambabu Gundla ◽  
Ramana Reddy Bobbala

: A Three component Synthesis of novel 5-phenyl-2-(thiophen-2-yl)-4-(trifluoromethyl)-5H-indeno [1,2-b] [1,8] naphthyridin-6(11H)-one derivatives (4a-n) were prepared using 6-phenyl/(thiophen-2-yl)-4-(trifluoromethyl)pyridin-2-amine, 1H-indene-1,3(2H)-dione and aryl aldehyde using 40% aq. HF with good yield. All the synthesized compounds were screened against Gram-positive and Gram-negative bacterial strains and different Candida strains by well diffusion method. Compounds 4c, 4f and 4g showed promising activity on Bacillus subtilis strain and compounds 4c and 4g showed promising activity towards Candida albicans starains.


2003 ◽  
Vol 07 (11) ◽  
pp. 755-760 ◽  
Author(s):  
Tatyana O. Philippova ◽  
Boris N. Galkin ◽  
Oksana Yu. Zinchenko ◽  
Maria Yu. Rusakova ◽  
Vladimir A. Ivanitsa ◽  
...  

The antimicrobial activity of new meso-tetrakis(N-methyl-6-quinolinyl)-substituted porphyrins and meso-tetrakis(N-methyl-6-quinolinyl)-substituted chlorins is described. The dark toxicity and photosensitising potentials of free-base (TQP and TQC) and its Sn(IV)-complexes [(TQP)Sn(IV) and (TQC)Sn(IV)] were tested on Gram-positive (Staphylococus aureus), Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria and two species of yeasts (Candida albicans and Rhodotorula bogoriensis). The results described in this paper show that TQP and (TQP)Sn(IV) did not inhibit the growth of S. aureus in the dark, but efficiently photosensitize the inactivation of this Gram-positive bacteria. These porphyrins have no appreciable photosensitizing activity towards Gram-negative bacteria. However, (TQP)Sn(IV) shows high dark toxicity against E. coli and P. aeruginosa. The free-base derivatives demonstrated dark activity only in the case of P. aeruginosa. We suppose that these meso-tetrakis(N-methyl-6-quinolinyl)-substituted porphyrins can bind to the Gram-negative bacteria outer membrane receptors that transported vitamin B12. The meso-substituted chlorins TQC and (TQC)Sn(IV) have shown similar efficiency in the dark- and photoinactivation of S. aureus. They revealed a middle level of dark toxicity towards Gram-negative bacteria. The Sn(IV)-complex of chlorin in comparison with free base and metalloporphyrins are more effective in photoinactivation of Gram-negative bacteria. Yeasts, such as Candida albicans and Rhodotorula bogoriensis are more sensitive to photodynamic inactivation as bacterial cells. The effects of (TQP)Sn(IV) and (TQC)Sn(IV) are more expressed than effects of free bases.


Author(s):  
L. Rajanna ◽  
N. Santhosh Kumar ◽  
N. S. Suresha ◽  
S. Lavanya

The in vitro antibacterial assay was carried out against both Gram positive (B. cerus and S. aureus) and Gram negative (E. coli and K. pneumoniae) bacteria. Floral petals of 20 different species of plants were collected and tested for antibacterial activity. The result showed that the petals were active against both Gram positive and Gram negative. Out of 20 floral petals tested, 19 floral petals exhibited antibacterial activity against selected bacterial strains. The minimal inhibitory zone of floral petal discs against human pathogenic bacteria varies from 2 – 6 mm. Rosa carolina and Ruellia tuberosa showed significance inhibition zone for all the bacterial strains while Lantana camara does not show inhibition zone for any of these pathogenic bacteria.


2020 ◽  
Vol 71 (2) ◽  
pp. 422-435
Author(s):  
Farag A. El-Essawy ◽  
Abdulrahman I. Alharthi ◽  
Mshari A. Alotaibi ◽  
Nancy E. Wahba ◽  
Nader M. Boshta

A novel series of 3-, 4-substituted, and 3,4-di substituted quinazoline derivatives were prepared via various cyclized regents and most of the newly prepared compounds evaluated for their antimicrobial activities in vitro against Gram-positive, Gram-negative bacterial strains and fungi strains. The structures of the quinazoline derivatives have been confirmed using spectroscopic analyses (IR, NMR, and EI-MS). Some of the synthesized derivatives displayed a moderate antimicrobial activity in comparison with reference drugs, for example compounds 13d, 15a, 17b, 18b, 18d, 25, and 29a-c. Among the synthesized compounds, the pyrimidoqunazoline derivative 6c elicited the highest activity.


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