Exploring the antibiofilm effects on Escherichia coli biofilm associated with colon cancer and anticancer activities on HCT116 cell line of bee products.

The association between dysbiotic microbiota biofilm and colon cancer has recently begun to attract attention. In the study, the apitherapeutic effects of bee products (honey, bee venom, royal jelly, pollen, perga and propolis) obtained from the endemic Yigilca ecotype of Apis mellifera anatoliaca were investigated. Antibiofilm activity were performed by microplate assay using crystal violet staining to measure adherent biofilm biomass of Escherichia coli capable of forming biofilms. Bee venom showed the highest inhibition effect (73.98%) at 50% concentration. Honey, perga and royal jelly reduced biofilm formation by >50% at all concentrations. The antiproliferation effect on the HCT116 colon cancer cell line was investigated with the water­soluble tetrazolium salt­1 assay. After 48 h of honey application at 50% concentration, cell proliferation decreased by 86.51%. The high cytotoxic effects of royal jelly and bee venom are also remarkable. Additionally, apoptotic pathway analysis was performed by ELISA using caspase 3, 8 and 9 enzyme-linked immunosorbent assay kits. All bee products induced a higher expression of caspase 9 compared with caspase 8. Natural products that upregulate caspase proteins are promising therapeutic targets for proliferative diseases.

Biological evaluation of benzothiazoles obtained by microwave-green synthesis.

Benzothiazole compounds are known as an important bicyclic ring system with multiple applications. These compounds have a wide range of biological activities, including anticancer, antimicrobial, anti-inflammatory and antiviral activities. In this study, benzothiazole compounds were synthesized and their various biological activities were examined. The synthesized benzothiazoles were evaluated for their antimicrobial properties against various bacterial and fungal strains. The compound 6e is most active ligand in the series against bacteria and fungi as compared to standard antibiotics. Especially, this compound significant effect against Staphylococcus aureus (32.00 ± 1.73 mm). These compounds exhibited potent anticancer activity against gastrointestinal cancer cells, demonstrating their potential as therapeutic agents. The lowest antiproliferative response after administration of the compounds was observed in HCT116 cells, while the most effective antiproliferative response was observed in AGS cells (> 10 µg/mL). In all cell lines, 40 and 100 µg/mL application values of the selected compounds showed significant increases in the expression of caspase-3, 8 and 9. We also utilized a computational docking approach to investigate the interaction of these benzothiazoles with VEGFR-2 kinase. Our docking studies showed that compounds 6a and 6d may be promising therapeutic agents against gastrointestinal system cancers due to their ability to bind to VEGFR-2 kinase.

[Investigation of Biofilm Formation, Anti-Quorum Sensing Activity and Antimicrobial Resistance in Corynebacterium Species Isolated from Clinical Samples]. / Klinik Örneklerden Izole Edilen Corynebacterium Türlerinde Biyofilm Olusumunun, Anti-Quorum Sensing Aktivitesinin ve Antimikrobiyal Direnç Durumunun Arastirilmasi.

An increasing number of different clinical infections caused by Corynebacteria have been reported in the last decade. The aim of this study was to evaluate the antibiotic resistance rates, biofilm formation capacities and to investigate the ''anti-quorum-sensing (anti-QS)'' activities of corynebacteria, which were divided into three groups according to the type of growth in culture (pure, with another pathogenic bacterium and polymicrobial growth). In total 240 Corynebacterium spp. isolates from different clinical specimens sent to the medical microbiology laboratories of Düzce University Faculty of Medicine Hospital and Basaksehir Çam and Sakura City Hospital between June 2021 and June 2022 were classified into three groups: pure, isolated with another pathogen and polymicrobial, according to their growth patterns in culture. Bacteria were identified by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) Biotyper (Bruker, Germany) at an external centre. Antibiotic susceptibilities were determined by disc diffusion method and for vancomycin broth microdilution method was used. Results were interpreted according to EUCAST recommendations. The biofilm-forming properties of the isolates were determined quantitatively. Bioactive components of 17 isolates with strong biofilm formation were extracted and anti-QS activity was determined by agar diffusion method using Chromobacterium violaceum ATCC 12472 strain and then violacein pigment production was measured quantitatively. Of the 240 Corynebacterium spp. isolates, 138 (58%) were pure, 52 (22%) were isolated with another pathogen and 50 (20%) were part of a polymicrobial infection. Of the isolates, 140 were identified as C.striatum, 34 as C.amycolatum and 24 as Corynebacterium afermentans. When the antibiotic resistance rates of the Corynebacterium isolates were analysed according to the groups, the resistance rates to rifampicin and tetracycline antibiotics were found to be statistically significantly lower in the polymicrobial group than in the other groups. The resistance rates to penicillin, clindamycin, ciprofloxacin, moxifloxacin, rifampicin, tetracycline and linezolid were 96.7%, 88.3%, 86.3%, 73.8%, 62.5%, 59.2% and 0.8%, respectively. While all isolates were susceptible to vancomycin, linezolid resistance was detected in two C.afermentans isolates. When the biofilm formation ability was analysed, it was observed that 87 (36.3%) isolates formed biofilm. The biofilm formation rate of the isolates in the polymicrobial growth group was lower than the other two groups. The anti-QS activity of 17 isolates with strong biofilm formation was investigated and none of the Corynebacterium extracts tested were found to have anti-QS activity (inhibition of violacein pigment production without inhibiting bacterial growth) in the QS study with C.violaceum, whereas five isolate extracts had antibacterial activity (inhibition of bacterial growth). Four of the bacterial extracts with antimicrobial activity belonged to C.amycolatum and one to C.afermentans. In conclusion, when both antibiotic resistance rates and biofilm formation rates were analysed, the corynebacteria growing in culture with another pathogen showed similar characteristics to the corynebacteria growing as a pure culture. Therefore, it was thought that corynebacteria growing with another pathogen should not be ignored. In addition, the antimicrobial effects of some corynebacterial extracts suggested that more QS studies should be carried out with microbiota bacteria.

Antimicrobial, Antiproliferative Effects and Docking Studies of Methoxy Group Enriched Coumarin-Chalcone Hybrids.

Methoxy group enriched eight coumarin-chalcone hybrid derivatives were synthesized. Antimicrobial/ antiproliferative activities were tested against eight human pathogenic microorganisms and four cancer cell lines (AGS, HepG2, MCF-7 and PC-3), respectively. Antimicrobial results showed that most of the compounds were almost more active than used standard antibiotics. Cytotoxicity results showed that 2,3,4-trimethoxyphenyl and thiophene containing structures have promising antiproliferative effects against AGS gastric cell lines with ∼5 µg/ml IC50 values. At the same time, 2,4-dimethoxyphenyl bearing derivative exhibited the lowest IC50 values against HepG2 (∼10 µg/ml) and PC-3 (∼5 µg/ml) cell lines. Particularly, the cell viabilities of MCF-7 cell lines were remarkably inhibited by all the compounds with lower IC50 values. Therefore, molecular docking studies between hybrid ligands and quinone reductase-2 enzyme (regulates in MCF-7 cancer cells) were performed. The results demonstrated that all the derivatives can smoothly interact with interested enzyme in agreement with the experimental results. Finally, ADME parameters were studied to reveal drug-likeness potentials of the coumarin-chalcone hybrids.

Evaluating antimicrobial and antioxidant capacity of endemic Phlomis russeliana from Turkey and its antiproliferative effect on Human Caco-2 Cell Lines.

In this study, the antimicrobial, antioxidant and antitumor activity of ethanol extracts obtained from Phlomis russeliana (Sims.) Lag. ex Benth. (Lamiaceae) were evaluated. Disc diffusion and microdilution methods were used to test the extracts for antimicrobial activity against seven bacteria strains (Bacillus cereus ATCC 7064, Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 6538P, Escherichia coli ATCC 10538, Proteus vulgaris ATCC 6899, Salmonella typhimurium CCM 5445 and Pseudomonas aeruginosa ATCC 27853) and four yeast strains (Kluyveromyces fragilis ATCC 8608, Rhodotorula rubra ATCC 70403, Debaryomyces hansenii DSM 70238 and Candida albicans ATCC 10239). Notably, they were more effective against the yeast strains than the bacterial strains. Of the yeast cultures, D. hanseii was among the most susceptible, having an inhibition zone of 16.2 mm with minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of 64(128)µg/ml, respectively. For cytotoxic determination, Caco-2 cells were cultured as per ATCC protocol, and were treated with log concentrations (5-80 mg/ml) of P. russeliana. The potency of cell growth inhibition for each extract was expressed as an IC50 value. Moreover, oxidant capacity was evaluated via TOC assay. This product induced antiproliferative activity of 31.33% at 40 mg/ml and 20.96% at 80 mg/ml, without toxic effects on cells, although the oxidant capacity was decreased to 27.06 ± 0.7 nm in the 80 mg/ml-applied group compared to 47.9 ± 1.8 nm in the untreated one. Advanced pharmacological studies are needed to further evaluate P. russeliana for distinctive features.

Investigation of plasmid mediated AmpC beta-lactamases in Escherichia coli and Klebsiella pneumoniae isolates by phenotypic and genotypic.

OBJECTIVE: To investigate the susceptibility and specificity of the phenotypic methods to determine plasmidmediated AmpC. METHODS: The cross-sectional study was conducted at Duzce University Faculty of Medicine, Microbiology Laboratory from January 2015 to June 2016, and comprised Escherichia coli and Klebsiella pneumonia isolates intermediate susceptible or resistant to cefoxitine. Combined disk diffusion test, double disc synergy test, agar gradient test and polymerase chain reaction were used to detect plasmid-mediated AmpC. RESULTS: Of the 2024 E. coli samples, 44(2.17%), and of the 792 K. pneumoniae samples, 16(2%) were included. Combined disk diffusion test had susceptibility of 68% and specificity of 50%; double disc synergy test 24% and 82%; and agar gradient test 40% and 68%. Of the isolates positively detected by polymerase chain reaction method, more than one gene region positivity was detected in 15(25%) isolates. CONCLUSION: All three phenotypic methods were found to be insufficient to detect plasmid-mediated AmpC positivity.

Thio-Schiff bases derived from 2,2'-disulfanedianiline via nanocerium oxide: antimicrobial effect and antiproliferative effects in melanoma cells.

In this study, the synthesis of dimeric disulfide-Schiff bases was carried out using two methods. The structures of the obtained Schiff bases were elucidated by various spectroscopic methods as well as elemental analysis. The Schiff base derivative compounds (3a-6) were screened for in vitro antibacterial activity against multidrug-resistant microorganisms using microdilution method. All the tested compounds showed varying inhibition zones against the pathogens. According to MIC results, the compound 2 was shown strong inhibitory activity against all the tested microorganisms compared to antibiotics. In addition, all the tested compounds showed different antiproliferative effects on the melanoma cell line (B16F10). Our synthesized dimeric disulfide-Schiff bases have shown significant various effects.