In this study, the leaf of Eugenia uniflora, an ornamental plant, was evaluated for its phytochemical constituents, antioxidant property and antimicrobial activity. The methanol extract of the leaf was partitioned into hexane, ethyl acetate and aqueous fractions. The antioxidant activities of the crude extract and fractions were performed using 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method, and IC50 values were calculated. The antimicrobial activity was tested against five bacteria strains (Pseudomonas aeruginosa, Escherichia coli, Micrococcus varians, Klebsiella pneumonia, Staphylococcus aureus) and two fungal strains (Saccharomyces cerevisiae, Aspergillus niger) using agar well diffusion method. Phytochemical screening indicated the presence of phenols, flavonoids, alkaloids, tannins, cardiac glycosides, saponin glycosides, saponins and anthraquinones in the leaf. The ethyl acetate fraction showed highest antioxidant activity (IC50 value of 0.919 mg/ml) compared with reference standard ascorbic acid (IC50 value of 0.859 mg/ml). The plant fractions demonstrated good antibacterial activities. The ethyl acetate fraction showed MIC values of 1.25 mg/mL, against P. aeruginosa and E. coli; 2.50 mg/mL against A. niger and 5.00 mg/mL against M. varians, K. pneumonia and S. cerevisiae while the aqueous fraction had MIC values of 0.625 mg/mL against S. cerevisiae; 1.25 mg/mL against P. aeruginosa, M. varians, K. pneumonia and A. niger and 2.5 mg/mL against Escherichia coli. The hexane fraction had MIC value of 1.25 mg/mL against Staphylococcus aureus. The results indicate that Eugenia uniflora leaf is rich in natural antioxidants and bioactive compounds which may provide health benefits and serve in the management of bacterial and fungal infections.

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h i g h l i g h t s • Biodegradation of crude and processed oils using indigenous isolates was evaluated. • Four major bacteria strains were able to utilize petroleum as energy source. • Both aliphatic and aromatic components of crude petroleum were reduced differently. • There is evidence that petroleum degradation capabilities could be plasmid encoded.

PurposeIncreasing rates of clonal spread of fecal blaTEM bacilli remains a huge concern to the community health with resultant high morbidity. The fecal carriage and clonal diversity of blaTEM within the communities in Southwest Nigeria were surveyed.Materials and methodsEnteric bacilli obtained from fresh fecal samples randomly collected from community residents were biotyped and profiled for antibiotic susceptibility. Resistant strains were typed for beta-lactamase, extended-spectrum beta-lactamases (ESBL), AmpC and carbapenemase production while the R-plasmid carriage was detected and mating activities were examined. The presence of blaTEM gene was assayed by PCR and its phylodiversity determined with 16sRNA genomic profiling.ResultsEscherichia coli have the highest (28.6%) occurrence rate and Pseudomonas aeruginosa (20.5%) showing significant resistance to beta-lactamase inhibitors (ampicillin, cefuroxime and cefotaxime), and high-level multidrug resistance of more than 15.2% rate to ampicillin, cefuroxime, ceftazidime, tetracycline and imipenem. E. coli and Klebsiella oxytoca, are the highest beta-lactamase, ESBL and AmpC producers encoded with high molecular weight R-plasmid (>11.0 kbp) and significant rate of conjugation and transformational activities. Only 2/14, 1/13 and 1/6 ESBL-type of E. coli, K. oxytoca and Enterobacter cloaca, expressed blaTEM gene, clustering into five different phylodiverse groups with close genomic relatedness with other bacilli.ConclusionThis is an indication of clonal dissemination of ESBL blaTEM encoded enteric bacilli having high phylodiverse characteristics through fecal carriage in the Nigerian community which requires public health education, food and environmental hygiene for its prevention.