scholarly journals Studies on the antibacterial properties of some basic derivatives of cholane and norcholane

1947 ◽  
Vol 134 (877) ◽  
pp. 538-543 ◽  
Keyword(s):  
Staphylococcus Aureus ◽  
Surface Tension ◽  
Antibacterial Activity ◽  
Antibacterial Properties ◽  
Lactobacillus Helveticus ◽  
Bacteriostatic Activity ◽  
Gram Positive ◽  
Gram Negative ◽  
Derivatives Of

A series of basic derivatives of cholane and norcholane has been examined for bacteriostatic activity against the Gram-positive Staphylococcus aureus and Lactobacillus helveticus and the Gram-negative Bacillus lactis aerogenes . The basic derivatives, in general, were more highly bacteriostatic against the Gram-positive organisms than against the Gram-negative. Of the compounds studied, the highest antibacterial activity was shown by 3:7:12-trihydroxy-23-guanido-norcholane hydrochloride. No relationship was apparent between the lowering of the surface tension of the medium induced by the compounds and their bacteriostatic activity.

SYNTHESIS AND ANTIBACTERIAL ACTIVITY OF NEW DERIVATIVES OF 2-OXO-2,5-DIHYDROFURANS CONTAINING AN OXOTHIAZOLIDINYLIDENE RING

2020 ◽  
Vol 54 (1 (251)) ◽  
pp. 12-16
Author(s):  
G.G. Tokmajyan ◽  
L.V. Karapetyan ◽  
R.V. Paronikyan ◽  
H.M. Stepanyan
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Shigella Flexneri ◽  
Antibacterial Activities ◽  
Gram Positive ◽  
Gram Negative ◽  
Esherichia Coli ◽  
Derivatives Of

ring were successfully synthesized based on thiosemicarbazones of 3-acetyl-2-oxo-2,5-dihydrofurans. The synthesized compounds exhibited moderate to defined antibacterial activities against Gram-positive (Staphylococcus aureus 209P and 1) and Gram-negative (Shigella Flexneri 6858, Esherichia coli 0–55) bacteria compared to furazolidone.

Structure-Activity Relationship and Antimicrobial Evaluation of N-Phenylpyrazole Curcumin Derivatives

2020 ◽  
Vol 16 (4) ◽  
pp. 481-488
Author(s):  
Heli Sanghvi ◽  
Satyendra Mishra
Keyword(s):  
Antibacterial Activity ◽  
Gram Negative Bacteria ◽  
Pyrazole Derivatives ◽  
Gram Positive ◽  
Gram Negative ◽  
E Coli ◽  
Curcumin Derivatives ◽  
Structure Activity ◽  
Electron Donating Groups ◽  
Derivatives Of

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.

scholarly journals Chemical Composition and Antibacterial Activity of the Essential Oil of Espeletia nana

2012 ◽  
Vol 7 (5) ◽  
pp. 1934578X1200700 ◽  
Author(s):  
Alexis Peña ◽  
Luis Rojas ◽  
Rosa Aparicio ◽  
Libia Alarcón ◽  
José Gregorio Baptista ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Chemical Composition ◽  
Essential Oil ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Disk Diffusion Method ◽  
Gram Negative ◽  
Gram Positive Bacteria

The essential oil of the leaves of Espeletia nana Cuatrec, obtained by hydrodistillation, was analyzed by GC-MS, which allowed the identification of 24 components, which made up 99.9% of the oil. The most abundant compounds were α-pinene (38.1%), β-pinene (17.2%), myrcene (15.0%), spathulenol (4.2%), bicyclogermacrene (4.0%), α-zingiberene (4.0%), and γhimachalene (3.7%). Antibacterial activity was tested against Gram-positive and Gram-negative bacteria using the agar disk diffusion method. Activity was observed only against Gram-positive bacteria. MIC values were determined for Staphylococcus aureus ATCC 25923(200 μg/mL) and Enterococcus faecalis ATCC 29212 (600 μg/mL).

scholarly journals A New Prenylated Flavanoid with Antibacterial Activity from Propolis Collected in Egypt

2010 ◽  
Vol 5 (1) ◽  
pp. 1934578X1000500 ◽  
Author(s):  
Ashraf El-Bassuony ◽  
Sameh AbouZid
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Bacillus Cereus ◽  
Spectroscopic Methods ◽  
Gram Positive ◽  
Gram Negative

A novel prenylated flavanoid, isonymphaeol-D (1), together with two known compounds, isonymphaeol-B (2) and nymphaeol-B (3), were isolated from Egyptian propolis. The structures of the isolated compounds were determined by various spectroscopic methods. 1 exhibited antibacterial activity against Gram-positive (Bacillus cereus, Staphylococcus aureus) and Gram-negative strains (Serratia sp., Pseudomonos sp., Escherichia coli).

Synthesis of Nano-Hydroxyapatite from Snakehead (Channa striata) Fish Bone and its Antibacterial Properties

2020 ◽  
Vol 840 ◽  
pp. 293-299
Author(s):  
Poedji Loekitowati Hariani ◽  
Muryati Muryati ◽  
Muhammad Said ◽  
Salni Salni
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Antibacterial Properties ◽  
Fish Bone ◽  
Molar Ratio ◽  
Temperature Variations ◽  
Gram Negative ◽  
Fish Bones ◽  
Channa Striata

Nano-hydroxyapatite was synthesized by coprecipitation method and tested its antibacterial properties. Nano-hydroxyapatite was synthesized using CaO precursors from snakehead (Channa striata) fish bones and (NH4)2HPO4. The synthesis was carried out with temperature variations of 30, 60, 80, and 100 °C. Antibacterial activity was determined using two types of bacteria, namely gram-positive and gram-negative. The XRD spectra show that the highest peak is hydroxyapatite synthesized at a temperature of 100 °C. Hydroxyapatite produced from various synthesis temperatures has the size of nanoparticles in the range 37.32-49.27 nm. The nano-hydroxyapatite functional groups are characterized using FTIR, the analysis indicate the presence of OH, CO32‒ and PO43‒. The molar ratio Ca/P is obtained of 1.71 approaching theoretical hydroxyapatite of 1.67. The resulted nano-hydroxyapatite has significant antibacterial properties to Escherichia coli and Staphylococcus aureus.

Antibacterial Activity of Amine-Functionalized Zeolite NaY against Staphylococcus aureus ATCC6538 and Escherichia coli ATCC11229

2015 ◽  
Vol 761 ◽  
pp. 402-406 ◽  
Author(s):  
Siti Aishah Mohd Hanim ◽  
Nik Ahmad Nizam Nik Malek ◽  
Zaharah Ibrahim ◽  
Mashitah Mad Salim ◽  
Nur Isti'anah Ramli ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Gram Positive ◽  
Gram Negative ◽  
Zeolite Nay ◽  
Amine Functionalized ◽  
Diffusion Technique

The antibacterial activity of functionalized zeolite NaY (CBV100) with different concentrations of 3-aminopropyltriethoxysilane (APTES) (0.01, 0.05, 0.20 and 0.40 M) was studied against Staphylococcus aureus ATCC 6538 (Gram positive) and Escherichia coli ATCC 11229 (Gram negative) through disc diffusion technique (DDT). The characterization of functionalized zeolite NaY with fourier transform infrared (FTIR) spectroscopy indicated the attachment of APTES on zeolite NaY. Through DDT, the inhibition zone of functionalized zeolite NaY increased proportionally to the amount of the amine-functional group attached onto zeolite NaY. Functionalized zeolite NaY showed higher antibacterial activity against Gram-positive compared to Gram-negative bacteria. It can be concluded from this study that amine-functionalized zeolite NaY shows evidence of antibacterial activities.

scholarly journals Physicochemical and Antibacterial Properties of Chitosan Extracted from Waste Shrimp Shells

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
José Carlos Vilar Junior ◽  
Daylin Rubio Ribeaux ◽  
Carlos Alberto Alves da Silva ◽  
Galba Maria De Campos-Takaki
Keyword(s):  
Antibacterial Activity ◽  
Antibacterial Properties ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Degree Of Deacetylation ◽  
Shrimp Shells ◽  
Shrimp Shell ◽  
Ft Ir ◽  
High Degree

This research aims to study the production of chitosan from shrimp shell (Litopenaeus vannamei) of waste origin using two chemical methodologies involving demineralization, deproteinization, and the degree of deacetylation. The evaluation of the quality of chitosan from waste shrimp shells includes parameters for the yield, physical chemistry characteristics by infrared spectroscopy (FT-IR), the degree of deacetylation, and antibacterial activity. The results showed (by Method 1) extraction yields for chitin of 33% and for chitosan of 49% and a 76% degree of deacetylation. Chitosan obtained by Method 2 was more efficient: chitin (36%) and chitosan (63%), with a high degree of deacetylation (81.7%). The antibacterial activity was tested against Gram-negative bacteria (Stenotrophomonas maltophiliaandEnterobacter cloacae) and Gram-positiveBacillus subtilisand the Minimum Inhibitory Concentrations (MIC) and the Minimum Bactericidal Concentration (MBC) were determined. Method 2 showed that extracted chitosan has good antimicrobial potential against Gram-positive and Gram-negative bacteria and that the process is viable.

scholarly journals Antibacterial Properties of Some Cyclic Organobismuth(III) Compounds

2005 ◽  
Vol 49 (7) ◽  
pp. 2729-2734 ◽  
Author(s):  
Toshiaki Kotani ◽  
Daisuke Nagai ◽  
Kensuke Asahi ◽  
Hitomi Suzuki ◽  
Fumiaki Yamao ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Properties ◽  
Cell Number ◽  
Viable Cell Number ◽  
Electron Microscopic ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Ring Compounds ◽  
Medical Disorders

ABSTRACT Bismuth compounds are known for their low levels of toxicity in mammals, and various types of bismuth salts have been used to treat medical disorders. As part of our program to probe this aspect of bismuth chemistry, cyclic organobismuth compounds 1 to 8 bearing a nitrogen or sulfur atom as an additional ring member have been synthesized, and their antimicrobial activities against five standard strains of gram-negative and gram-positive bacteria were assessed. The eight-membered-ring compounds, compounds 1 to 3, exhibited MICs of less than 0.5 μg/ml against Staphylococcus aureus and were more active than the six-membered ones, compounds 5 to 8 (MICs, 4.0 to 16 μg/ml). The gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis, and Enterococcus faecalis) were more susceptible to both types of ring compounds than the gram-negative ones (Escherichia coli and Pseudomonas aeruginosa). Treatment with polymyxin B nonapeptide increased the susceptibility of E. coli to cyclic organobismuth compounds, indicating the low permeability of the outer membrane of gram-negative bacteria to the compounds. Compound 1 also had activity against methicillin-resistant S. aureus, which had an MIC for 90% of the hospital stock strains of 1.25 μg/ml. The killing curves for S. aureus treated with compound 1 or 3 revealed a static effect at a low dose (2× the MIC). However, when S. aureus was treated with 10× the MIC of compound 1 or 3, there was an approximately 3-log reduction in the viable cell number after 48 h of treatment. Electron microscopic inspection demonstrated a considerable increase in the size of S. aureus and the proportion of cells undergoing cell division after treatment with compound 1 at 0.5× the MIC.

scholarly journals Plasmon Resonance of Silver Nanoparticles as a Method of Increasing Their Antibacterial Action

Antibiotics ◽  
2018 ◽  
Vol 7 (3) ◽  
pp. 80 ◽  
Author(s):  
Alexander Vasil’kov ◽  
Ruslan Dovnar ◽  
Siarhei Smotryn ◽  
Nikolai Iaskevich ◽  
Alexander Naumkin
Keyword(s):  
Staphylococcus Aureus ◽  
Silver Nanoparticles ◽  
Plasmon Resonance ◽  
Photoelectron Spectroscopy ◽  
Antibacterial Properties ◽  
Petri Dish ◽  
Aureus Strain ◽  
Gram Positive ◽  
Gram Negative ◽  
X Ray

In this article, a series of silver-containing dressings are prepared by metal-vapor synthesis (MVS), and their antibacterial properties are investigated. The antibacterial activity of the dressings containing silver nanoparticles (AgNPs) against some Gram-positive, and Gram-negative microorganisms (Staphylococcus aureus, Staphylococcus haemolyticus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Moraxella spp.) has been determined. Based on the plasmon resonance frequency of these nanoparticles, the frequency of laser irradiation of the dressing was chosen. The gauze bandage examined showed pronounced antibacterial properties, especially to Staphylococcus aureus strain. When 470 nm laser radiation, with a power of 5 mW, was applied for 5 min, 4 h after inoculating the Petri dish, and placing a bandage containing silver nanoparticles on it, the antibacterial effect of the latter significantly increased—both against Gram-positive and Gram-negative microorganisms. The structure and chemical composition of the silver-containing nanocomposite were studied by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS). The synthesized AgNPs demonstrate narrow and monomodal particle size distribution with an average size of 1.75 nm. Atoms of metal in Ag/bandage system are mainly in Ag0 state, and the oxidized atoms are in the form of Ag-Ag-O groups.

scholarly journals Antibacterial Properties of Propolis

Molecules ◽  
2019 ◽  
Vol 24 (11) ◽  
pp. 2047 ◽  
Author(s):  
Izabela Przybyłek ◽  
Tomasz M. Karpiński
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Antibacterial Properties ◽  
Bacterial Strains ◽  
Complex Composition ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
The World

Researchers are continuing to discover all the properties of propolis due to its complex composition and associated broad spectrum of activities. This review aims to characterize the latest scientific reports in the field of antibacterial activity of this substance. The results of studies on the influence of propolis on more than 600 bacterial strains were analyzed. The greater activity of propolis against Gram-positive bacteria than Gram-negative was confirmed. Moreover, the antimicrobial activity of propolis from different regions of the world was compared. As a result, high activity of propolis from the Middle East was found in relation to both, Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) strains. Simultaneously, the lowest activity was demonstrated for propolis samples from Germany, Ireland and Korea.

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