scholarly journals Synthesis and Characterization of Chemical Compounds Derived From Benzohydrazide and Evaluation of Their Antibacterial Activities

2021 ◽  
Vol 8 (1) ◽  
pp. 5-10
Author(s):  
Maryam Alizadeh ◽  
Ashraf Kariminik ◽  
Ali Akbari

Background: The antimicrobial resistance of pathogenic bacteria has emerged as a major health problem in recent years. Extensive research has been conducted to find new antimicrobial agents. Objectives: The aim of this study was to examine the antibacterial activities of benzohydrazide derivatives. Methods: Manganese hydrogen sulfate choline chloride was applied in a simple method for synthesizing benzohydrazide derivatives. Antibacterial activities of the derivatives were assessed against Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Bacillus subtilis, diphtheroids, Salmonella enterica, Serratia marcescens, Pseudomonas aeruginosa, and Klebsiella pneumoniae. The structure of the synthesized compounds was determined employing 1 H/13C NMR and Fourier-transform infrared (FT-IR) spectroscopy. The reactions were carried out in choline chloride dissolved in water at room temperature. Results: The results of this study showed that benzohydrazide derivatives had very desired antibacterial activities against the assessed bacteria. Conclusions: Further investigations are required to assess the safety and efficacy of benzohydrazide derivatives as antibacterial agents in vivo and in vitro.

1999 ◽  
Vol 43 (6) ◽  
pp. 1429-1434 ◽  
Author(s):  
Bob Goodson ◽  
Anton Ehrhardt ◽  
Simon Ng ◽  
John Nuss ◽  
Kirk Johnson ◽  
...  

ABSTRACT Peptoids differ from peptides in that peptoids are composed of N-substituted rather than alpha-carbon-substituted glycine units. In this paper we report the in vitro and in vivo antibacterial activities of several antibacterial peptoids discovered by screening combinatorial chemistry libraries for bacterial growth inhibition. In vitro, the peptoid CHIR29498 and some of its analogues were active in the range of 3 to 12 μg/ml against a panel of gram-positive and gram-negative bacteria which included isolates which were resistant to known antibiotics. Peptoid antimicrobial activity againstStaphylococcus aureus was rapid, bactericidal, and independent of protein synthesis. β-Galactosidase and propidium iodide leakage assays indicated that the membrane is the most likely target of activity. Positional isomers of an active peptoid were also active, consistent with a mode of action, such as membrane disruption, that does not require a specific fit between the molecule and its target. In vivo, CHIR29498 protected S. aureus-infected mice in a simple infection model.


2019 ◽  
Vol 7 (9) ◽  
pp. 278 ◽  
Author(s):  
Lorenzo

The advent of multidrug resistance among pathogenic bacteria is devastating the worth of antibiotics and changing the way of their administration, as well as the approach to use new or old drugs. The crisis of antimicrobial resistance is also due to the unavailability of newer drugs, attributable to exigent regulatory requirements and reduced financial inducements. The emerging resistance to antibiotics worldwide has led to renewed interest in old drugs that have fallen into disuse because of toxic side effects. Thus, comprehensive efforts are needed to minimize the pace of resistance by studying emergent microorganisms and optimize the use of old antimicrobial agents able to maintain their profile of susceptibility. Chloramphenicol is experiencing its renaissance because it is widely used in the treatment and prevention of superficial eye infections due to its broad spectrum of activity and other useful antimicrobial peculiarities, such as the antibiofilm properties. Concerns have been raised in the past for the risk of aplastic anemia when chloramphenicol is given intravenously. Chloramphenicol seems suitable to be used as topical eye formulation for the limited rate of resistance compared to fluoroquinolones, for its scarce induction of bacterial resistance and antibiofilm activity, and for the hypothetical low impact on ocular microbiota disturbance. Further in-vitro and in vivo studies on pharmacodynamics properties of ocular formulation of chloramphenicol, as well as its real impact against biofilm and the ocular microbiota, need to be better addressed in the near future.


2014 ◽  
Vol 70 (a1) ◽  
pp. C311-C311
Author(s):  
Diana Tomchick ◽  
Ranjit Deka ◽  
Chad Brautigam ◽  
Wei Liu ◽  
Michael Norgard

Treponema pallidum, an obligate parasite of humans and the causative agent of syphilis, has evolved the capacity to exploit host-derived metabolites for its survival. Flavin-containing compounds are essential cofactors that are required for metabolic processes in all living organisms, and riboflavin is a direct precursor of the cofactors FMN and FAD. Unlike many pathogenic bacteria, Treponema pallidum cannot synthesize riboflavin; we recently described a flavin-uptake mechanism composed of an ABC-type transporter [1]. However, there is a paucity of information about flavin utilization in bacterial periplasms. We have identified the TP0796 lipoprotein as a previously uncharacterized Mg2+-dependent FAD pyrophosphatase/FMN transferase within the ApbE superfamily [2,3]. Biochemical and structural investigations revealed that the enzyme has a unique bimetal Mg2+ catalytic center. Furthermore, the pyrophosphatase activity is product-inhibited by AMP, indicating a possible role for this molecule in modulating FMN and FAD levels in the treponemal periplasm. The ApbE superfamily was previously thought to be involved in thiamine biosynthesis, but our characterization of TP0796 prompts a renaming of this superfamily as a periplasmic flavin-trafficking protein (Ftp). Treponemal Ftp (Ftp_Tp) is the first structurally and biochemically characterized metal-dependent FAD pyrophosphatase/FMN transferase in bacteria. We have shown in vitro and in vivo that Ftps from several types of pathogenic bacteria are capable of flavinylating proteins through covalent attachment of FMN via a phosphoester bond to threonine residues of an appropriate sequence signature. Progress on the structural characterization of a product of this post-translational modification will be presented. This new paradigm for a bacterial flavin utilization pathway may prove to be useful for future inhibitor design.


Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3132 ◽  
Author(s):  
Xianghui Ruan ◽  
Cheng Zhang ◽  
Shichun Jiang ◽  
Tao Guo ◽  
Rongjiao Xia ◽  
...  

A series of myricetin derivatives containing amide, thioether, and 1,3,4-thiadiazole moieties were designed and synthesized, and their antiviral and antibacterial activities were assessed. The bioassays showed that all the title compounds exhibited potent in vitro antibacterial activities against Xanthomonas citri (Xac), Ralstonia solanacearum (Rs), and Xanthomonas oryzae pv. Oryzae (Xoo). In particular, the compounds 5a, 5f, 5g, 5h, 5i, and 5l, with EC50 values of 11.5–27.3 μg/mL, showed potent antibacterial activity against Xac that was better than the commercial bactericides Bismerthiazol (34.7 μg/mL) and Thiodiazole copper (41.1% μg/mL). Moreover, the in vivo antiviral activities against tobacco mosaic virus (TMV) of the target compounds were also tested. Among these compounds, the curative, protection, and inactivation activities of 5g were 49.9, 52.9, and 73.3%, respectively, which were better than that of the commercial antiviral Ribavirin (40.6, 51.1, and 71.1%, respectively). This study demonstrates that myricetin derivatives bearing amide, thioether, and 1,3,4-thiadiazole moieties can serve as potential alternative templates for the development of novel, highly efficient inhibitors against plant pathogenic bacteria and viruses.


Author(s):  
Juliane Maria dos Santos Silva ◽  
Jackson Roberto Guedes da Silva Almeida ◽  
Cristiane dos Santos Cerqueira Alves ◽  
Daniel Amando Nery ◽  
Livia Maria Oliveira Damasceno ◽  
...  

Introduction: Nowadays, several bacteria have acquired resistance to available antimicrobial agents making necessary the search for new therapeutic alternatives. Plectranthus amboinicus L. is a succulent and aromatic herb, popularly known as thick leaf mint, used in popular medicine for the treatment of colds, digestive diseases, asthma, headache and to fight pathogenic bacteria activity. In view the antimicrobial activity of P. amboinicus this study had as aim to review publications involving researches about antimicrobial activity of this species. Materials and Methods: For this, PubMed, Scopus, Science Direct and Scielo databases were consulted in November 2020 using the keywords Plectranthus amboinicus and antimicrobial activity. In vitro and/or in vivo studies on the antimicrobial activity of the species in the last 10 years were considered. Results: The main microorganisms evaluated were: Klebsiella pneumoniae, Mycobacterium tuberculosis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and some Candida species. The essential oils had carvacrol, germacrene D, thymol and camphor as main constituents. Most studies evaluated the antimicrobial activity using broth dilution and agar diffusion methods. In most studies essential oil, extracts and/or isolated substances showed significant antimicrobial activity. Synergistic activity was also observed through association with antibiotics. Conclusion: P. amboinicus has therapeutic potential for antimicrobial treatments and can be an alternative to the treatment of resistant microorganisms and that further in vivo and clinical studies with the species are still needed.


2008 ◽  
Vol 57 (5) ◽  
pp. 617-625 ◽  
Author(s):  
Domen Jaklič ◽  
Aleš Lapanje ◽  
Klemen Zupančič ◽  
Dragica Smrke ◽  
Nina Gunde-Cimerman

Maggot therapy, also known as biosurgery, is an ancient method for the healing of chronic infected wounds. Although clinicians have reported on the beneficial activities of the Lucilia sericata larvae that have been used for healing chronic wounds, the selectivity of this therapy against the different pathogenic micro-organisms that are found in chronic wounds has never been analysed. In the present study, we have investigated the in vitro activities of larval excreta/secreta both against selected bacterial strains that frequently occur in chronically infected wounds, and against bacteria isolated directly from the larvae and their excreta/secreta. Additionally, the antibacterial activities were investigated in in vivo studies, by comparing bacterial diversity in wounds before and after the application of L. sericata larvae. In conclusion, larval therapy is highly recommended, particularly for the treatment of wounds infected with Gram-positive bacteria, like Staphylococcus aureus, but less so for wounds infected with Gram-negative bacteria, especially Proteus spp. and Pseudomonas spp. strains. Bacteria from the genus Vagococcus were resistant to the maggot excreta/secreta.


2019 ◽  
Author(s):  
Chem Int

New copper complexes, [Cu(phen)2(Thy)]2Cl and [Cu(phen)2(Ad)]2Cl (phen = 1,10-phenantroline, Ad (Adenine, a purine nucleobase) and Thy (Thymine, a pyrimidine nucleobase)), were synthesized and characterized by atomic absorption spectroscopy (AAS), conductivity measurement, UV-visible and infrared (IR) techniques. The complexes were tested for their antimicrobial activity against two gram positive and two gram negative bacterial strains. The results of in vitro antimicrobial activities were compared with the commercially available antimicrobial agents (ciprofloxacin and chloramphenicol). This comparative study has demonstrated that [Cu(phen)2(Thy)]2Cl inhibited the growth of methicillin resistant Staphylococcus aureous (MRSA), Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumonia) better than chloramphenicol by 11.25%, 19.41% and 25.35%, respectively. It also showed better activities than ciprofloxacine on MRSA and K. pneumoniae by 2.50% and 12.13%, respectively. Similarly, [Cu(phen)2(Ad)]2Cl demonstrated better inhibitions than chloramphenicol against MRSA, E. coli and K. pneumoniae by 11.24%, 2.48% and 9.06%, respectively. Therefore, after in vivo cytotoxicity investigations, these complexes could be considered as potential antimicrobial agents.


Marine Drugs ◽  
2019 ◽  
Vol 17 (6) ◽  
pp. 355 ◽  
Author(s):  
Tse-Kai Fu ◽  
Sim-Kun Ng ◽  
Yi-En Chen ◽  
Yuan-Chuan Lee ◽  
Fruzsina Demeter ◽  
...  

More than 80% of infectious bacteria form biofilm, which is a bacterial cell community surrounded by secreted polysaccharides, proteins and glycolipids. Such bacterial superstructure increases resistance to antimicrobials and host defenses. Thus, to control these biofilm-forming pathogenic bacteria requires antimicrobial agents with novel mechanisms or properties. Pseudomonas aeruginosa, a Gram-negative opportunistic nosocomial pathogen, is a model strain to study biofilm development and correlation between biofilm formation and infection. In this study, a recombinant hemolymph plasma lectin (rHPLOE) cloned from Taiwanese Tachypleus tridentatus was expressed in an Escherichia coli system. This rHPLOE was shown to have the following properties: (1) Binding to P. aeruginosa PA14 biofilm through a unique molecular interaction with rhamnose-containing moieties on bacteria, leading to reduction of extracellular di-rhamnolipid (a biofilm regulator); (2) decreasing downstream quorum sensing factors, and inhibiting biofilm formation; (3) dispersing the mature biofilm of P. aeruginosa PA14 to improve the efficacies of antibiotics; (4) reducing P. aeruginosa PA14 cytotoxicity to human lung epithelial cells in vitro and (5) inhibiting P. aeruginosa PA14 infection of zebrafish embryos in vivo. Taken together, rHPLOE serves as an anti-biofilm agent with a novel mechanism of recognizing rhamnose moieties in lipopolysaccharides, di-rhamnolipid and structural polysaccharides (Psl) in biofilms. Thus rHPLOE links glycan-recognition to novel anti-biofilm strategies against pathogenic bacteria.


PLoS ONE ◽  
2016 ◽  
Vol 11 (2) ◽  
pp. e0135961 ◽  
Author(s):  
Ann M. Czyzewski ◽  
Håvard Jenssen ◽  
Christopher D. Fjell ◽  
Matt Waldbrook ◽  
Nathaniel P. Chongsiriwatana ◽  
...  

2004 ◽  
Vol 279 (50) ◽  
pp. 52346-52352 ◽  
Author(s):  
Wangrong Yang ◽  
Ian F. Moore ◽  
Kalinka P. Koteva ◽  
David C. Bareich ◽  
Donald W. Hughes ◽  
...  

The tetracycline antibiotics block microbial translation and constitute an important group of antimicrobial agents that find broad clinical utility. Resistance to this class of antibiotics is primarily the result of active efflux or ribosomal protection; however, a novel mechanism of resistance has been reported to be oxygen-dependent destruction of the drugs catalyzed by the enzyme TetX. Paradoxically, thetetXgenes have been identified on transposable elements found in anaerobic bacteria of the genusBacteroides. Overexpression of recombinant TetX inEscherichia colifollowed by protein purification revealed a stoichiometric complex with flavin adenine dinucleotide. Reconstitution ofin vitroenzyme activity demonstrated a broad tetracycline antibiotic spectrum and a requirement for molecular oxygen and NADPH in antibiotic degradation. The tetracycline products of TetX activity were unstable at neutral pH, but mass spectral and NMR characterization under acidic conditions supported initial monohydroxylation at position 11a followed by intramolecular cyclization and non-enzymatic breakdown to other undefined products. TetX is therefore a FAD-dependent monooxygenase. The enzyme not only catalyzed efficient degradation of a broad range of tetracycline analogues but also conferred resistance to these antibioticsin vivo. This is the first molecular characterization of an antibiotic-inactivating monooxygenase, the origins of which may lie in environmental bacteria.


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