Antibacterial properties and mode of action of new triaryl butene citrate compounds

Repurposing of Tamoxifen Against the Oral Bacteria

Objectives

Tamoxifen (TAM), which is used for treating breast cancer, has exhibited another important function as an antimicrobial agent. The objective of this study is to investigate the antibacterial action of TAM against the bacteria present in the human oral cavity.

Materials and Methods

The bacteria present in the human oral cavity were isolated from healthy individuals. Different concentrations of TAM were tested against the isolated bacteria. Additionally, bactericidal and bacteriostatic effects of TAM were also determined.

Results

Out of 23 isolated bacteria, a greater number of Gram-positive bacteria were highly susceptible to the low concentrations of TAM than Gram-negative bacteria. Kytococcus sedentarius, which is Gram-positive bacterium, and Pseudomonas stutzeri, which is Gram-negative bacterium, needed a high minimum inhibitory concentration value of TAM (2.5 mg/mL) to be inhibited by TAM's bacteriostatic action. Resistance to TAM was also observed in three strains of Gram-positive and four strains of Gram-negative bacteria.

Conclusion

TAM has shown a potential antibacterial effect against the bacteria present in the oral cavity, especially against Gram-positive bacteria. This effect is mostly bacteriostatic. This study also found bacterial resistance toward TAM.

Antimicrobial, Antitumor and Side Effects Assessment of a Newly Synthesized Tamoxifen Analog

BACKGROUND

Tamoxifen citrate is a very prevalent drug marketed under several trade names like Apo-Tamox, Nolvadex, Tamec, Tamizam, and Tamoplex. This molecule is approved by the FDA for breast cancer treatment. Some studies have shown that tamoxifen has anti-tuberculosis and antiparasitic activities. Like any drug, tamoxifen possesses side effects, more or less dangerous.

AIMS

Basically, this work is a comparative study that aims to: primarily compare the antimicrobial and antitumor activities of tamoxifen and a newly synthesized tamoxifen analog; and to determine the molecule with lesser side effects.

METHODS

Three groups of mice were injected with tamoxifen citrate and compound 2(1,1-bis[4-(3- dimethylaminopropoxy)phenyl]-2-phenyl-but-1-ene dihydrochloride) at doses corresponding to C1 (1/10), C2 (1/50), and C3 (1/100) to compound 2 lethal dose (LD50 = 75 mg/kg) administered to adult mice. A group of noninjected mice served as a study control.

RESULTS

Experimental results suggest that compound 2 has better antitumor and antimicrobial activity than tamoxifen citrate besides its lower toxicity effects.

CONCLUSION

The results obtained from the present study confirmed the antitumor and antimicrobial effect of tamoxifen citrate and its hematological side effects. Compound 2 seems to be more effective than tamoxifen citrate for antitumor and antimicrobial treatment while having less hematological side effects and less disruption of the blood biochemical parameters. These findings encourage us to perform further studies on compound 2 and test it for other therapeutic uses for which tamoxifen was found effective.

Selective Estrogen Receptor Modulators (SERMs): Mechanistic Insights Against Microbial Infections

Background:

Infections are one of the leading causes of death worldwide and currently available treatments remain unsatisfactory due to rise in the cases of antimicrobial resistance. Thus, there is a need for the development of new drugs with different mechanisms of action. However, the development of new antimicrobials agents is a long and expensive process. Hence, most of the pharmaceutical companies are

Methodology:

The data related to SERMs and microbial infection has been extracted from Pub Med (from January 1997 to December 2018). A total of 101 studies have been published from 1997 -2018 regarding SERMs and microbial infections.

Results:

On the basis of inclusion and exclusion criteria, 25 studies have been included for the analysis of level of evidence regarding antimicrobial effects of SERMs. Emerging reports have indicated the antimicrobial property of selective estrogen receptor modulators (SERMs) against normal and resistant strains under in vitro and in vivo conditions against wide variety of microorganisms through different mechanisms of action.

Conclusion:

In conclusion, SERMs could be developed as a broad spectrum antimicrobial agent alone or in combination with existing antimicrobial agents.

Antibiotic-non-antibiotic combinations for combating extremely drug-resistant Gram-negative 'superbugs'

The emergence of antimicrobial resistance of Gram-negative pathogens has become a worldwide crisis. The status quo for combating resistance is to employ synergistic combinations of antibiotics. Faced with this fast-approaching post-antibiotic era, it is critical that we devise strategies to prolong and maximize the clinical efficacy of existing antibiotics. Unfortunately, reports of extremely drug-resistant (XDR) Gram-negative pathogens have become more common. Combining antibiotics such as polymyxin B or the broad-spectrum tetracycline and minocycline with various FDA-approved non-antibiotic drugs have emerged as a novel combination strategy against otherwise untreatable XDR pathogens. This review surveys the available literature on the potential benefits of employing antibiotic-non-antibiotic drug combination therapy. The apex of this review highlights the clinical utility of this novel therapeutic strategy for combating infections caused by 'superbugs'.

Simultaneous Production of Formylated and Nonformylated Enterocins L50A and L50B as well as 61A, a New Glycosylated Durancin, by Enterococcus durans 61A, a Strain Isolated from Artisanal Fermented Milk in Tunisia

Enterococcus durans 61A, a broad-spectrum strain, was isolated from artisanal fermented dairy products. The strain is a multibacteriocin producer, free from virulence genes, and could be considered a good candidate for application in food preservation. In the present study, E. durans 61A was shown to produce simultaneously formylated and nonformylated forms of leaderless enterocins L50A and L50B as well as 61A, a new glycosylated durancin. Bacteriocins were characterized using mass spectrometry. Formylation was found to increase enterocin antimicrobial activity of enterocin L50A (8×) and, to a lesser extent, the activity of L50B (2×). Durancin 61A was found glycosylated by two hexoses (glucose and arabinose) and exhibited broad-spectrum inhibition against Gram-positive and Gram-negative bacteria and fungal spores. Durancin 61A was highly bactericidal at 15.6 μg/mL (10× the MIC) on Listeria innocua HPB13 and seems to target bacterial membrane as shown by ion efflux and transmission electron microscopy.

Efficacy of a novel ferrocenyl diaryl butene citrate compound as a biocide for preventing healthcare-associated infections

The antiseptic and disinfectant potential of a formulation containing a tamoxifen analogue was assessed according to European standards and pharmacopeia in comparison with a commercial antiseptic product.