M. Sciberras, M. Pipová, I. Regecová, P. Jevinová and S. Demjanová
The purpose of this study was to detect the antibiotic resistance of forty-one Escherichia coli isolates from the intestinal contents of slaughtered broiler chickens using the disk diffusion method according to Kirby-Bauer. Mueller-Hinton agar plates were inoculated with 0.1 ml overnight broth cultures of individual E. coli isolates and the disks with the following concentrations of antibiotics were applied onto them: ampicillin (10 μg), cefotaxime (30 μg), gentamicin (10 μg), streptomycin (10 μg), azithromycin (15 μg), tetracycline (30 μg), ciprofloxacin (30 μg) and levofloxacin (3 μg). After the incubation at 37 °C for 16—18 hours, the inhibition zones were measured and interpreted in accordance with the Clinical and Laboratory Standard Institute (CLSI) zone diameter breakpoints. Almost all E. coli isolates showed resistance to tetracycline (92.68 %), most of them were resistant to gentamicin (75.61 %) and levofloxacine (70.73 %). Phenotypic resistance to tetracycline was further confirmed with the help of the Polymerase Chain Reaction (PCR) procedure focused on the presence of specific tet(A) and tet(B) genes. These genes were detected in all 41 E. coli isolates. On the contrary, E. coli isolates were highly susceptible to both azithromycin and streptomycin. In conclusion, the study highlighted the role of commensal E. coli bacteria isolated from the intestines of broiler chickens as an important reservoir of tetracycline resistance genes.
One of the traditional plants that have so many pharmacological effects is chilli fruit (Capsicum sp.) that belong to the family Solanaceae. Around the world, five varieties of Capsicum are known, i. e., C. annuum, C. frutescens, C. chinense, C. baccatum, and C. pubescens. Chilli peppers are known for causing the sensation of heat or burning when consumed. The heat sensation is incited by the type and the amount of a group of capsaicinoids; the alkaloids found only in chilli pepper pods. A widely used heat measurement of chilli peppers is the SHU (Scoville Heating Unit). This measurement is the highest dilution of a chilli pepper extract at which heat can be detected by a taste panel. Nowadays, the Scoville organoleptic test has been largely replaced by chromatographic methods which are considered to be more reliable and accurate. The HPLC (High Pressure Liquid Chromatography) method was used for the determination of capsaicin content in various fresh and dried peppers from the genera C. chinense. Currently, based on the results of HPLC, the hottest pepper has been Bhut Jolokia, followed by Habanero Red Savina and Habanero Yellow etc. The content of capsaicin in dried chillies is 7-10 times higher compared to fresh ones.