In Vitro effects of petroleum ether, dichloromethane, methanolic and aqueous leaf extracts of Eucalyptus grandis on selected multidrug-resistant bacteria.

BACKGROUND: The emergence and spread of antimicrobial resistance is of grave concern, requiring the search for newer and more effective antimicrobials to combat infections caused by resistant microbes. This study assessed the antimicrobial effects of Eucalyptus grandis crude extracts against selected multidrug resistant bacteria. METHODOLOGY: Four different crude leaf extracts of E. grandis were prepared using petroleum ether, dichloromethane, methanol, and water, with the aid of the Soxhlet extraction method. These were screened against methicillin-resistant Staphylococcus aureus (MRSA), multidrug resistant Pseudomonas aeruginosa, and multidrug resistant Escherichia coli, using the agar well diffusion method. Phytochemical screening was carried out to evaluate the bioactive phytochemical constituents responsible for the antimicrobial effect. RESULTS: Each of the extracts, except for the one prepared from water, had antimicrobial activity against the screened bacteria. The non-polar petroleum ether extract had the highest antimicrobial activity (19.33-24.33 mm), including bactericidal effects, compared to the medium polar dichloromethane and polar methanol extracts, which recorded zone diameter ranges of 14.33-16.67 mm and 16.33-17.67 mm, respectively. The Gram-negative bacteria (E. coli and P. aeruginosa) were the least susceptible in comparison with the Gram-positive bacterium (MRSA), probably owing to differences in their cell wall structures. Furthermore, phytochemical screening indicated the presence of alkaloids, tannins, saponins, terpenoids, and flavonoids. CONCLUSION: The findings suggest that E. grandis could be potentially useful in the treatment of infections caused by multidrug resistant bacteria.

Occurrence, ecological risk assessment and source apportionment of pharmaceuticals, steroid hormones and xenoestrogens in the Ghanaian aquatic environments.

Elevated levels of pharmaceuticals, steroid hormones and xenoestrogens (PSHXEs) in the aquatic environment pose a serious threat to the ecological balance. The endocrine disrupting PSHXEs in aquatic systems are linked to several adverse effects like reproductive health impairment, feminization, high mortality rate, decreased biodiversity etc. This study, therefore, sought to investigate the occurrence and the ecological risks posed by some selected PSHXEs and also conduct source apportionment of the PSHXEs in the Ghanaian aquatic environments. A total of 48 samples comprising 24 sediments and water each were taken from six waterbodies in Ghana. The samples were extracted using SPE cartridges for water and QuEChERS-dSPE for sediments. The analyses were done using Shimadzu Prominence UFLC 20A series. Ecological risk assessments were also conducted with the aid of USEPA T.E.S.T., whereas source apportionments were conducted using the APCS-MLR receptor model. Elevated mean total levels of PSHXEs ranging between 12,187 and 52,117 ng/L and 2,022-6,047 ng/g for water and sediment samples respectively were found. The risk quotients (RQ > 1) suggested a high risk posed by PSHXEs in water to organisms at the three trophic levels and also to benthic organisms in sediments of the Ghanaian aquatic environments for a short-term period. The APCS-MLR receptor model suggested three statistically significant sources (p < 0.05) designated by signature PSHXEs as domestic (major), mix hospital and industrial and agricultural waste sources. The source apportionment suggested increased use of steroid estrogens and anabolic drugs among the Ghana populace.

Staphylococcus aureus Nasopharyngeal Carriage and Antimicrobial Resistance among Adults with Sickle Cell Disease at the Korle Bu Teaching Hospital in Accra, Ghana.

Background: Sickle cell disease (SCD) patients are an important risk group for Staphylococcus aureus (S. aureus) carriage and infections. Little is, however, known about the nasopharyngeal carriage epidemiology of the pathogen in this vulnerable population. Aim: The aim of this study was to evaluate S. aureus and methicillin-resistant S. aureus (MRSA) nasopharyngeal carriage prevalence, carriage determinants, and antimicrobial resistance among SCD adults in Ghana. Methodology: Nasopharyngeal swabs, obtained from 200 SCD adults recruited at the Korle Bu Teaching Hospital, were cultured for S. aureus, and these isolates were subjected to antimicrobial susceptibility testing via the Kirby-Bauer method. Results: The prevalence of S. aureus carriage was 41.5% (n = 83), and that of MRSA carriage was 1.0% (n = 2). Moreover, carriage of coagulase-negative Staphylococcus (CoNS) was the only determinant of S. aureus carriage identified (OR = 0.012, P < .0001). However, neither this variable nor the other features of the participants emerged as a determinant of MRSA carriage. The antimicrobial resistance rates decreased across penicillin (98.8%, n = 82), tetracycline (54.2%, n = 45), gentamicin (32.5%, n = 27), ciprofloxacin (21.7%, n = 18), erythromycin (18.1%, n = 15), clindamycin (10.8%, n = 9), amoxicillin-clavulanic acid (10.8%, n = 9), teicoplanin (1.2%, n = 1), and linezolid (0.0%, n = 0), and the multidrug resistance rate was 45.8% (n = 38). Conclusion: The nasopharyngeal carriage prevalence of S. aureus in the current study was high, while that of MRSA was low. The isolates were highly resistant to several of the antibiotics tested, but not teicoplanin and linezolid, making these antibiotics suitable for treatment of S. aureus infections among the SCD population.