Molecular Characterisation and Antimicrobial Activities of Novel Substituted Ferrocenyl Chalcone Derivatives

The increasing issues of drug-resistant bacteria has quickly become a global concern as infections spread from healthcare settings to the wider community. The rapid spread of these infections is partly facilitated by a decrease in the development of new drugs. Because of their antimicrobial properties, ferrocenyl chalcones, which are organometallic chalcone derivatives, have gained attention from researchers. Early classes of ferrocenyl chalcones were reportedly cytotoxic, which encouraged the need to develop next-generation ferrocenyl chalcone compounds that are less toxic. One-to-one dilutions of stock ferrocenyl chalcone solution and MHB, resulting in the formation of small, brown particles, was suggested to arise from iron ion chelation of casein hydrolysate, a component of MHB. After solubilisation in DMSO, each of the iodine-containing ferrocenyl chalcone compounds, changed from deep red to dark brown. There was no evidence that iodine was displaced when diethyl ether was used. Using 2-fold broth microdilution, results demonstrated that five of the ten methylated ferrocenyl chalcones, possessed greater antimicrobial activity against resistant and non-resistant Gram-positive organisms than Gram-negative organisms. These compounds contain increasing alkyl chain lengths from pentyl to decyl on ring ‘B’ of the compounds. The results of MTT assays of Gram-positive bacteria indicated that there were no viable cells, where the mean (± SD) percentage of actively respiring cells were observed. SEM images of bacterial cells, which were treated with an active ferrocenyl chalcone, exhibited significant cell membrane damage as ultrastructurally observed. Key findings of this research indicate that further investigations into these compounds are required so that the inhibition of biofilm formation and the cytotoxicity towards mammalian cells are clearly defined. Additionally, the results advance the possibility that these newly developed ferrocenyl chalcone compounds could be important antimicrobial agents in the treatment of infections from clinically resistant bacteria in an environment where current treatments are failing

Ferrocenyl Chalcone Derivatives as Possible Antimicrobial Agents

The swift spread of infections caused by drug-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA), has quickly become a worldwide concern as infections spread from healthcare settings to the wider community. While ferrocenyl chalcones, which are chalcone derivatives with antimicrobial activity, have gained attention from researchers, further study is needed to assess their cytotoxicity. Ten newly developed chalcones, in which ring A was replaced with a ferrocenyl moiety and ring B contained increasing alkyl chain lengths from 1 to 10 carbons, were assessed. Using twofold broth microdilution, the minimum inhibitory concentration (MIC) of five of the ten compounds were lower against Gram-positive organisms (MICs from 0.008 mg ml−1 to 0.063 mg ml−1) than Gram-negative organisms (MICs = 0.125 mg ml−1). These novel ferrocenyl chalcone compounds were effective against three types of clinically isolated drug-resistant S. aureus, including an MRSA, and against other non-resistant clinically isolated and laboratory-adapted Gram-positive bacteria. The same compounds inhibited growth in non-resistant bacteria by potentially obstructing cellular respiration in Gram-positive bacteria. Images obtained through scanning electron microscopy revealed fully lysed bacterial cells once exposed to a selected compound that showed activity. The results indicate that these newly developed compounds could be important antimicrobial agents in the treatment of infections from clinically resistant bacteria

Infection control in the UK: an antimicrobial resistance perspective

The spread of healthcare-associated infections has become a matter of global concern. These infections, which were once solely limited to hospital settings, have emerged in the community. Reduced infection control practices strengthen this rapid spread of infections, which has led to the increase in the occurrence of multidrug resistant organisms. The state of infection control in the United Kingdom is of extreme importance because of several reported cases of infections caused by these organisms. In addition to antimicrobial usage in human medicine, antimicrobial agents used in agriculture must be considered as major factors in the prevalence of resistant organisms and the implications to the UK. However, this increased occurrence of antimicrobial resistant bacteria and their resulting infections could be reduced with the application of effective policies for antibiotic use in agricultural environments, stringent decontamination and sterilisation techniques and better regulations that encourage the search for, and development of, new and novel drugs. Keywords: Infection control, healthcare associated infections, antimicrobial drug resistance, prophylaxis, health policy

Novel Ferrocenyl Chalcone Compounds as Possible Antimicrobial Agents

The increased prevalence of drug-resistant bacteria has quickly become a global concern as infections spread from healthcare settings to the wider community. The rapid spread of infections caused by bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) is partly facilitated by misuse and abuse of conventional drug therapies and a decreased development of new drugs. Chalcones, which are a class of plant-based flavonoids, have become the focus of much research in medicinal chemistry since they inhibit bacterial growth. Ferrocenyl chalcones, which are chalcone derivatives, have gained further attention from researchers. In these compounds, ring A is replaced with a ferrocenyl moiety. Key characteristics of ferrocenyl chalcones include their small size, lipophilicity, an important feature allowing diffusion across cell membranes, ease of chemical modification and accessible one-electron-oxidation potential. Early classes of ferrocenyl chalcones were reportedly toxic to mammalian cells. This cytotoxicity to mammalian cells encouraged the need to develop next-generation ferrocenyl chalcone compounds that are less toxic. Using 2-fold broth microdilution, results demonstrated that 5 of the 10 newly developed ferrocenyl chalcones possessed greater antimicrobial activity against Gram-positive organisms than Gram-negative organisms. These novel ferrocenyl chalcone compounds were active against three (3) types of drug-resistant S. aureus, including a MRSA, and other non-resistant Gram-positive bacteria. These compounds contain increasing alkyl chain lengths from 5-10 on ring B. The same compounds inhibited growth in non-resistant bacteria by obstructing cellular respiration in Gram-positive bacteria. The results indicate that these newly developed compounds could be important antimicrobial agents in the treatment of infections from clinically resistant bacteria