scholarly journals Antimicrobial activity of levofloxacin – M33 peptide conjugation or combination

MedChemComm ◽  
2016 ◽  
Vol 7 (2) ◽  
pp. 258-262 ◽  
Author(s):  
Federica Ceccherini ◽  
Chiara Falciani ◽  
Martina Onori ◽  
Silvia Scali ◽  
Simona Pollini ◽  
...  

M33 is a branched antimicrobial peptide against Gram-negative bacteria. We reported its conjugation with levofloxacin and its antibacterial activity.

2021 ◽  
Vol 21 (5) ◽  
pp. 2879-2891
Author(s):  
Enrico Podda ◽  
M. Carla Aragoni ◽  
Massimiliano Arca ◽  
Giulia Atzeni ◽  
Simon J. Coles ◽  
...  

The reactivity of thiomorpholinium P-(4-methoxyphenyl)-N-thiomorpholin-amidodithiophosphonate (S-MorH+2)(S-Mor-adtp−) and morpholinium P-(4-methoxyphenyl)-N-morpholin-amidodithiophosphonate (O-MorH+2)(O-Mor-adtp−) towards nickel (II) dichloride hexahydrated is presented and the hydrolysis of the relevant metal complexes investigated. The hydrolytic products (S-MorH+2)2 [Ni(dtp)2]2− and (O-MorH+2)2[Ni(dtp)2]2− were characterized by means of FT-IR, 1H, and 31P NMR and XRD and the experimented P–N cleavage investigated and elucidated by means of DFT calculations. The antimicrobial activity of the neutral nickel complex [Ni(S-Mor-adtp)2] was tested against a set of Gram-positive and Gram-negative bacteria alongside with its nanodispersion in a silica matrix. The complex [Ni(S-Mor-adtp)2] did not show antibacterial activity, whilst the nano-dispersed sample [Ni(S-Mor-adtp)2]_SiO2 demonstrated inhibition to growth of Staphylococcus aureus. The nanocomposites were fully characterized by means of XRPD, TGA, SEM and dinitrogen sorption techniques.


2020 ◽  
Vol 49 (3) ◽  
pp. 207-214 ◽  
Author(s):  
Hatem E. Gaffer ◽  
Ismail I. Althagafi

Purpose The purpose of this paper is to synthesize some new azobenzene dyestuffs clubbed with thiazolidinone moiety and their solicitation in dyeing polyester fabrics representing their antibacterial evaluation. Design/methodology/approach Herein, the authors report the synthesis of new thiazolidinone moiety after the coupling of diazotized 4-aminoacetophenone with resorcinol. The newly synthesized dyes were characterized by IR, elemental analysis, mass spectroscopy and proton nuclear magnetic resonance (1H NMR) spectral studies. The characteristics of dyeing of these dyestuffs were evaluated at optimum conditions. Concurrent with dyeing of polyester fabric for synthesized dyes with their antibacterial activity was estimated. Antimicrobial activity of the dyed fabrics at different concentrations was evaluated against gram-positive and gram-negative bacteria. Findings Synthesized azobenzene dyestuffs clubbed with thiazolidinone dyes were applied on polyester fabrics. It was remarked that the modified dyes exhibited better colourfastness properties. Furthermore, the synthesized dyes revealed antimicrobial activity against gram-positive and gram-negative bacteria. Research limitations/implications The synthesized azobenzene dyes for polyester dyeing were not bore earlier. Practical implications The azobenzene dyes were accountable for giving improved colourfastness properties on polyester fabrics. Social implications The synthesized azobenzene derivatives are sensibly expensive and applicable dyes accompanied with good antimicrobial and anticancer activities. Originality/value A common process could be affording textiles of colour and antibacterial assets. The newly synthesized dyes containing thiazolidinone moieties with azobenzene coupler showed interesting disperse colourant for polyester with good antibacterial activity.


1969 ◽  
Vol 15 (9) ◽  
pp. 1067-1076 ◽  
Author(s):  
A. H. Amin ◽  
T. V. Subbaiah ◽  
K. M. Abbasi

Berberine sulfate was shown to possess antimicrobial activity against a wide variety of microorganisms including Gram-positive and Gram-negative bacteria, fungi, and protozoa. The antibacterial activity against Vibrio cholerae and Staphylococcus aureus was dependent on the inoculum size of the test organism and pH of the medium. A method of microbiological assay sensitive to 5–10 μg/ml of the drug was developed. The drug was shown to exert a more rapid antibacterial activity than chloramphenicol and tetracycline on V. cholerae, the K values being 2.4 ×10−2 sec−1, 7.8 × 10−3 sec−1, and 5.2 × 10−3 sec−1 respectively. Berberine sulfate was shown to be bacteriocidal to V. cholerae and bacteriostatic to S. aureus, at concentrations of 35 and 50 μg/ml. In both these organisms concentrations of 35 and 50 μg/ml of the drug inhibited ribonucleic acid (RNA) and protein synthesis almost immediately after the addition of the drug. There was little effect on deoxyribonucleic acid (DNA) synthesis at these concentrations.


2020 ◽  
Vol 10 (4) ◽  
pp. 639-654
Author(s):  
А. A. Meleshko ◽  
A. G. Afinogenova ◽  
G. E. Afinogenov ◽  
A. A. Spiridonova ◽  
V. P. Tolstoy

Metal and metal oxide nanoparticles (NPs) are promising antibacterial agents. They have a broad antimicrobial activity against both Gram-positive and Gram-negative bacteria, viruses, and protozoans. The use of NPs reduces the possibility of the microbial resistance development. This review briefly shows the general mechanisms and the main factors of antibacterial activity of NPs. In this article, a comprehensive review of the recent researches in the field of new antimicrobial agents with superior long-term bactericidal activity and low toxicity is provided. The review gives the examples of synthesis of double and triple nanocomposites based on following oxides: CuO, ZnO, Fe3O4, Ag2O, MnO2, etc. including metal and nonmetal doped nanocomposites (for example with Ag, Ce, Cr, Mn, Nd, Co, Sn, Fe, N, F, etc.). Compared with bactericidal action of individual oxides, the nanocomposites demonstrate superior antibacterial activity and have synergistic effects. For example, the antimicrobial activity of ZnO against both Gram-positive and Gram-negative bacteria was increased by -100% by formation of triple nanocomposites ZnO—MnO2—Cu2O or ZnO—Ag2O—Ag2S. Similar effect was showed for Ce-doped ZnO and Zn-doped CuO. The present article also provides the examples of nanocomposites containing NPs and organic (chitosan, cellulose, polyvinylpyrrolidone, biopolymers, etc.) or inorganic materials with special structure (graphene oxide, TiO2 nanotubes, silica) which demonstrate controlled release and longterm antibacterial activity. All of the considered nanocomposites and their combinations have a pronounced long-term antimicrobial effect including against antibiotic-resistant strains. They are able to prevent the formation of microbial biofilms on biotic and abiotic surfaces, have low toxicity to eukaryotic cells, demonstrate anti-inflammatory and woundhealing properties in compositions with polymers (sodium alginate, collagen, polyvinylpyrrolidone, etc.). The use of nanoscale systems can solve several important practical problems at the same time: saving of long-term antimicrobial activities while reducing the number of compounds, creation of new antimicrobial agents with low toxicity and reduced environmental impact, development of new biocidal materials, including new coatings for effective antimicrobial protection of medical devices.


2021 ◽  
Vol 3 (1) ◽  
pp. 1-5
Author(s):  
Poonam Sethi ◽  
Nandhagopal Karmegam

ABSTRACT Artabotrys odoratissimus R.Br.  (Annonaceae) a medium sizes shrub with hooks, sweet smelling flowers and aggregate fruits, was tested for activity against gram negative bacteria. The fruit of the experimental plant was extracted with water, methanol and toluene: methanol (2:1 v/v). Artabotrys fruits showed good antibacterial activity and produced zone of inhibition of 32mm. The methanolic extract of the fruit showed maximum zone of inhibition at 300 ?g/ml against Pseudomonas fluorescens. The present study clearly indicates that A. odoratissimus had a profound antimicrobial   activity and it may be useful in the treatment of various infectious caused by bacteria. Keywords: Artabotrys, Gram Negative Bacteria, Pseudomonas, Zone Of Inhibition


Molecules ◽  
2020 ◽  
Vol 25 (10) ◽  
pp. 2374
Author(s):  
Paula C. Alves ◽  
Patrícia Rijo ◽  
Catarina Bravo ◽  
Alexandra M. M. Antunes ◽  
Vânia André

We report herein three novel complexes whose design was based on the approach that consists of combining commercially available antibiotics with metals to attain different physicochemical properties and promote antimicrobial activity. Thus, new isostructural three-dimensional (3D) hydrogen bonding frameworks of pipemidic acid with manganese (II), zinc (II) and calcium (II) have been synthesised by mechanochemistry and are stable under shelf conditions. Notably, the antimicrobial activity of the compounds is maintained or even increased; in particular, the activity of the complexes is augmented against Escherichia coli, a representative of Gram-negative bacteria that have emerged as a major concern in drug resistance. Moreover, the synthesised compounds display similar general toxicity (Artemia salina model) levels to the original antibiotic, pipemidic acid. The increased antibacterial activity of the synthesised compounds, together with their appropriate toxicity levels, are promising outcomes.


2019 ◽  
Vol 40 (4) ◽  
pp. 531-536
Author(s):  
Md. Sirajul Islam ◽  
Md. Mokhlesur Rahman ◽  
Md. Mizanur Rahaman

Abstract Amphibians, like some animals and plants, defend themselves against various pathogenic organisms by producing and secreting various peptides and small molecules from granular skin glands. In this study, we evaluated for the first time, the antibiotic activity of the skin secretions of 8 different frog species (Euphlyctis cyanophlyctis, E. hexadactylus, Fejervarya teraiensis, F. asmati, F. syhadrensis, Hoplobatrachus tigerinus, Microhyla ornata and Polypedates leucomystax) from Bangladesh. These secretions were collected by a nonlethal approach through chemical stimulation and the antibacterial activity was evaluated by broth macrodilution method against some Gram-positive and Gram-negative bacteria. Our study revealed that all the skin secretions (8 out of 8) from the selected frogs have antimicrobial activity against Gram-positive bacteria and 7 out of 8 skin secretions possess antibacterial activity against Gram-negative bacteria tested. Further analysis of data showed that these secretions are significantly more effective against Gram-positive bacteria than Gram-negative bacteria.


2015 ◽  
Vol 2015 ◽  
pp. 1-6
Author(s):  
Mouna Bouzid ◽  
Raed Abdennabi ◽  
Mohamed Damak ◽  
Majed Kammoun

This paper describes the synthesis of a series of dihydroisoquinoline nitrones by isomerization of the corresponding oxaziridines. Nitrones4a–cwere obtained in excellent yields and high purity by a simple and effective method from the isomerization of oxaziridines. The synthesized compounds were also evaluated for their antibacterial activity against Gram-positive and Gram-negative bacteria and fungus.


Author(s):  
Ranganathan Kapilan

Wide range of plant extracts are used for medicinal purposes as they are very cheap, efficient, harmless and do not cause any side effects. Spices are parts of different plants and they add special aroma and taste to the food preparations. The aim of the study was to determine the antimicrobial activity of some important naturally grown spices against gram positive and gram negative pathogenic bacteria. Antibacterial activity of the spices was tested against gram positive bacteria Bacillus pumilus, Bacillus cereus and Staphylococcus aureus and gram negative bacteria Escherichia coli, Salmonella typhi and Pseudomonas aeruginosa using aqueous, ethanolic, methanolic and liquid nutrient extracts. Among all the extracts tested alcoholic extracts of Cardamom (Elettaria cardamom), clove (Eugenia caryophyllus) and lemongrass (Cymbopogoncitratus) showed maximum antimicrobial activity against gram negative bacteria while alcoholic extract of Cardamom (Elettaria cardamom) and lemongrass (Cymbopogoncitratus) showed maximum activity against gram positive bacteria. All the spices tested in this study proved that they have antibacterial activity and the maximum activity index (1.39) was exhibited by the ethanol extract of cardamom against E.coli.


Sign in / Sign up

Export Citation Format

Share Document