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The types and methods of use of antibiotics in poultry farms in Cameroon, residual levels and potential microbial resistance were determined. A questionnaire-based survey identified the different antibiotics used and high-performance liquid chromatography (HPLC) was used to determine residual levels of antibiotics. Pathogens were isolated, identified by use of commercial API kits and minimum inhibition concentration (MIC) was determined. Oxytetracyclin, tylocip and TCN (oxytetracycline, chloramphenicol and neomycin) were the most frequently used antibiotics. Antibiotics screened by HPLC were chloramphenicol, tetracycline and vancomycin. All of them except vancomycin were detected, and the concentration of these antibiotics was higher than the maximum residual limits (MRL) set by regulatory authorities. No residues of various antibiotics were found in egg albumen or yolk. The concentration of tetracycline was significantly higher in liver (150 ± 30 µg/g) than in other tissues. Foodborne pathogens, including Salmonella spp., Staphylococcus spp., Listeria spp., Clostridium spp. and Escherichia spp., were identified. Most of the pathogens were resistant to these various antibiotics tested. These findings imply the need for better management of antibiotic use to control sources of food contamination and reduce health risks associated with the presence of residues and the development of resistant pathogens by further legislation and enforcement of regulations on food hygiene and use of antibiotics.

The chemical composition of the essential oils of nine taxa from seven sections of Hypericum L. (Guttiferae; H. perforatum subsp. perforatum, H. perforatum subsp. veronense, H. calycinum, H. montanum, H. richeri subsp. richeri, H. hyssopifolium, H. hirsutum, H. hircinum subsp. majus, and H. tetrapterum) occurring in central Italy (Appennino Umbro-Marchigiano) was analyzed by GC/FID and GC/MS. A total of 186 compounds were identified in the different species and subspecies, accounting for 86.9-92.8% of the total oils. The major fraction of the oil was always represented by sesquiterpene hydrocarbons (30.3-77.2%), while quantitative differences occurred between the other classes of volatiles depending on the taxa considered. Chemical composition of the nine Hypericum entities with respect to the taxonomical classification was discussed. Essential oils obtained from six taxa, i.e., H. perforatum subsp. perforatum, H. perforatum subsp. veronense, H. calycinum, H. richeri subsp. richeri, H. hirsutum and H. tetrapterum, were also tested for their antimicrobial properties against five different microbial strains by the broth-microdilution method, and they were found to have significant activity (expressed as MIC) on B. subtilis, moderate activity on C. albicans and S. aureus, and weak activity on E. coli and E. faecalis, the most active being those from H. hirsutum, H. richeri subsp. richeri, and H. tetrapterum.

Essential oil from flowers (FL) and vegetative parts (VP) of Achillea ligustica (Asteraceae), naturalized after cultivation in central Italy, was investigated by GC-FID and GC-MS. The most abundant components were linalool, viridiflorol, beta-pinene, 1,8-cineole and terpinen-4-ol. The antioxidant assays (DPPH and ABTS radical scavenging assays, and beta-carotene bleaching test) demonstrated a moderate activity of essential oils. The antimicrobial activity was evaluated by the broth micro-dilution method on 6 microbial strains and showed to be quite strong against the cariogenic Gram-positive Streptococcus mutans, suggesting that this essential oil could be a valid candidate for anti-cariogenic formulations. Moderate cytotoxic activity was observed in assays on four tumour cell lines by MTT assay.

The essential oil obtained from different parts of Ferula glauca L. (formerly considered as a subspecies of F. communis) growing in Marche (central Italy), was analyzed for the first time by GC-FID and GC-MS. The major volatiles were (E)-caryophyllene and caryophyllene oxide in leaves, alpha-pinene, myrcene and germacrene D in flowers, alpha- and beta-pinene in fruits, (E)-beta-farnesene, myristicin and elemicin in roots, respectively. The differences in composition detected with respect to F. communis, made the volatile fraction a reliable marker to distinguish between them, and confirm the botanical data at the base of their discrimination. Furthermore, the oil was assayed for its antimicrobial activity by the broth microdilution method. B. subtilis was found to be the most sensitive microorganism, with the lowest MIC values.

Methanol-acetone extracts from aerial parts of seven entities of the genus Hypericum [H. perforatum L. subsp. perforatum, H. perforatum L. subsp. veronense (Schrank) Ces., H. montanum L., H. hyssopifolium Chaix, H. hirsutum L., H. hircinum L. subsp. majus (Aiton) N. Robson, H. tetrapterum Fr.] growing in the Appennino Umbro-Marchigiano (central Italy) were tested in vitro for their antimicrobial activity against two Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis), two Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and the yeast Candida albicans, by the Kirby-Bauer agar diffusion method. The two H. perforatum subspecies were particularly active against Gram-positive and Gram-negative bacteria, supporting the use of these plants in the traditional medicine of central Italy to treat wounds, skin and infectious diseases. However significant values of inhibition were given also by H. hirsutum against S. aureus and P. aeruginosa, and by H. hyssopifolium, H. hircinum subsp. majus and H. tetrapterum against C. albicans. These results suggest that hypericin and hyperforin are the main components responsible for antimicrobial activity, but not the only ones, as other extracts, showing a low level of these compounds, possess evident activity. Isolation of pure compounds from the most active extracts is in progress.

The aim of this study is the comprehensive (pre-operative, operative and post-operative) evaluation of the use of antibacterial drugs on a group of patients subjected to orthopaedical surgery. The data regarding 1000 orthopaedic surgical operations, corresponding to 1000 non-urgent patients, have been examined. This study reveals the incongruity in the use of antibacterial drugs in the orthopaedic surgical activity mainly in operative prophylaxis, but also the administration during the intra-operative period, and the use of the same drugs in the post operative period.