Objective : Silymarin and curcumin antimicrobial properties have been previously described against some infectious agents. The aims of the current study were the investigation of the antibacterial effects of these compounds on the expression of fimA, cdt, bla IMP1 and bla OXA-48 and AcrAB-TolC genes among multidrug-resistant Escherichia coli clinical isolates. Methods : A total of five carbapenemase-producing E. coli strains were included. All of them carried bla IMP1 and bla OXA-48, ACR-AB, cdt, fimA and QepA genes. The antibiotic susceptibility test, imipenem, cefotaxime and ceftazidime minimum inhibitory concentration (MIC) and combine disk and Carba NP-test for carbapenemase production were performed. Silymarin and curcumin minimum inhibitory and bactericidal concentrations [MIC and minimum bactericidal concentration (MBC), respectively] were determined. The effect of 25 μg/ml concentration was also evaluated against gene expression. The quantitative real-time PCR was performed for the evaluation of genes expression. Results : Silymarin MIC and MBC were 256 and more than 256 μg/ml, respectively. Moreover, curcumin MIC and MBC concentrations were 128 and 256 μg/ml, respectively. Silymarin down-expressed the ACR-AB, cdt, fimA genes and QepA genes significantly (P < 0.05), but conferred no significant effect on bla IMP nor bla OXA-48 genes. Moreover, curcumin down-expressed the ACR-AB, QepA and bla IMP genes significantly (P < 0.05), but exhibited no significant effect against bla OXA-48, cdt and fimA genes. Conclusion : In this study, curcumin and silymarin sub-MIC concentrations could significantly inhibit the expression of the ACR-AB, cdt, fimA, QepA and bla IMP genes at 25 μg/ml. Combating bacterial virulence is a proper strategy not only to inhibit the spread of infections, but also to prevent the appearance and spread of antibiotic nonsusceptible strains.

Background: In recent years, high attention has been given to the biological activities of natural compounds and their potential antimicrobial properties. Objective: In this study, the antibacterial properties of the extracts from tissue and peptides of Cerastoderma and Didacna were studied. Materials and Methods: samples of Cerastoderma and Didacna were collected and washed. Then, the soft tissues were cut and powdered, and concentrations of 16, 8, 4, 2, 1 and 0.5 of chloroform, ethanol and methanol, and in addition extract of enzymatic hydrolysis were prepared, and their antibacterial activities against Staphylococcus aureus, Escherichia coli and Salmonella paratyphi were investigated. The disc diffusion method was used for the evaluation of strains susceptibility. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were investigated for bacterial growth inhibition. Results: Methanolic and ethanolic extracts from Cerastoderma demonstrated higher growth inhibitory effects compared to those from Didacna on E. coli and S. paratyphi and exhibited similar activities against S. aureus at concentrations 16 and 8 ug/mL. In addition, chloroform extracts of Cerastoderma and Didacna displayed similar inhibitory effects on S. paratyphi and S. aureus at concentrations 16 and 8 ug/mL which was a suitable effect, and the extract from Cerastoderma was more effective. MIC and MBC of methanolic extracts were at the lowest level, especially against S. aureus. Conclusion: It was revealed that Cerastoderma and Didacna extracts were effective as antibacterial compounds on S. aureus, E. coli and S. paratyphi species as natural agents.

The continuing emergence or re-emergence of vector-borne zoonotic Q fever (caused by Coxiella burnetii) and Crimean Congo hemorrhagic fever (CCHF, caused by Orthonairovirus) include indispensable extraordinary threat around the world. Low infectious dose and long-term environmental residence are major risks. Wildlife and domestic livestock act as hosts or reservoirs of the CCHF virus and ticks are carriers. The disease also poses a threat to public health services owing to its epidemic potential, high case fatality ratio (up to 40%) as well as difficulties in treatment, prevention, and control. Q fever is another zoonotic febrile disease mainly affecting workers involved in farming livestock. The causative agent of Q fever causes abortion in livestock. The pathogen is shed in large numbers in the waste of infected animals (amniotic fluids and placenta during parturition) and is transmitted by inhalation of contaminated aerosols. Vaccination is the most effective way of protecting against Q fever. The main way to prevent Q fever is to avoid contact with animals, especially while animals are giving birth, or consumption of unpasteurized milk and contaminated dairy products. Due to the increasing importation of livestock to meet the growing demand for dairy and meat products, new diseases are likely to be introduced. In our growing globalized world, where trade between countries increases, it is necessary to conduct more research on zoonotic diseases and to monitor any possible disease introduction to new areas. A continuing surveillance program and pathogen testing are important in tracking the emergence of new pathogens.