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Background: The emergence of drug-resistant pathogens has been found to increase mortality and the therapeutic cost of infections around the world. Pseudomonas aeruginosa (P. aeruginosa), one of the multi-drug resistant pathogens, causes nosocomial and urinary tract infections. The increasing concerns about its morbid effects and resultant mortality have provoked intensive studies on alternative therapeutic solutions to the challenge posed by multidrug-resistant pathogens. Therefore, this study combines in vitro and in silico models to investigate the antimicrobial potential of Azadirachta indica (A. Juss) and Phyllanthus amarus (P. amarus) (Schum and Thonn) leaves of ethanolic extract on multidrug-resistant pathogenic P. aeruginosa. Methods: Standard procedures were used for the preparation of extracts, phytochemical screening, minimum inhibitory concentration, minimum bactericidal concentration, fractional inhibitory concentration, mechanism of action and gas chromatography-mass spectrophotometer (GCMS). In silico study was carried out by molecular docking of the extracts with MexB-resistant protein encoding the 6IIA-resistant gene of P. aeruginosa. Results: Many of the ligands had high docking scores which indicate a strong potential for use as drugs to counter the resistant genes. Ligands like Oleanolic acid (-9.8kcal/mol), of P. amarus and Azadirachtol (-10.2kcal/mol) of A. indica, had the best docking scores. The sensitivity assay done using P. aeruginosa as a target revealed that both A. indica and P. amarus were able to effectively inhibit the uropathogen at 350mg/ml concentration and with the same zone of inhibition of 20.50±0.33. The minimum inhibitory concentration result revealed that A. indica (300mg/ml) is less effective when compared to P. amarus (200mg/ml). The minimum bactericidal result revealed in a similar fashion that P. amarus (300mg/ml) was more effective than A. indica (350mg/ml) because of the lesser concentration required. Fractional inhibitory concentration shows that the combination of A. indica and P. amarus gives an additive effect (0.83). Mechanism of action result showed that the release of Sodium content was more in P. amarus (17.3Mol/L) than A. indica (12.3Mol/L) and it was released the least in protein (1.0Mol/L- A. indica; 3.6Mol/L- P. amarus). Conclusion: The in-silico studies revealed that A. indica had the ligand with the best docking score and greatest potential, while the in-vitro investigation revealed that P. amarus had a higher antibacterial potency against the multidrug resistant uropathogen P. aeruginosa than A. indica. [ABSTRACT FROM AUTHOR]

For the control and treatment of trypanosomiasis, a limited number of chemotherapeutic drugs with mild side effects are available. As a result, a quest for a less toxic herbal treatment for trypanosomiasis is needed. Ethanolic extract of A. gummifera leaf (EEAL) and aqueous extract of Albizia. gummifera leaf (AEAL) were tested for antitrypanosomal activity against Trypanosoma brucei brucei in vitro. We first compared the phytochemical concentrations of EEAL and AEAL and discovered that EEAL had higher phytochemical concentrations on average than AEAL: flavonoids (4.26 mg/g vs 2.50 mg/g); alkaloids (38.40 mg/g vs 19.80 mg/g); tannins (230.7 mg/g vs 45.74 mg/g) and saponins (128.66 vs 44.33g/g). From the result of phytochemical concentrations of the two compounds, the higher values observed in flavonoids and alkaloid of EEAL led us to hypothesize that EEAL would have greater trypanocidal activity. Following that, EEAL and AEAL were tested for antitrypanosomal activity in vitro. Forty µl of blood holding in about 25±8 parasites/field was mixed with 20 µl of the EEAL and AEAL solutions of 100, 80, 60 mg/ml to produce an efficacious test concentration of 25, 20 and 15 mg/ml, sequentially. The extracts inhibited parasite motility and eliminated the organisms at the concentrations used in vitro, except for 15 mg/ml AEAL and 20 mg/ml AEAL. Following the screening, the Albizia gummifera ethanolic extract found to have positive in vitro trypanocidal activity. More research is needed to determine the concentrations of the extract for the in vivo test.

Background: Concomitant bacterial pathogens associated with hepatitis B infection could further increase the stress on the liver of infected individuals thereby complicating the infection. Objective: This necessitates the need to evaluate the antibacterial activity of Citrus aurantium L. leaf extracts on bacteria isolated from blood of hepatitis B virus (HBV) positive individuals in Ondo State, Nigeria. Method: The leaf extracts of Citrus aurantium (aqueous, ethanol and N-hexane) were assessed for possible antibacterial activities against some isolated bacteria from blood samples of HBV positive individuals were conducted using agar well diffusion technique. Results: Proteus mirabilis, S. typhi, S. aureus, Kl. pneumoniae, Ps. aeruginosa, E. coli, S. pneumoniae and Ch. Violaceum were isolated. The most frequently encountered bacterial species was S. aureus (52%). The ethanol leaf extract exerted the highest growth inhibitory activity on S. aureus, Kl. pneumoniae, Ps. auruginosa and E. coli. The aqueous leaf extract exerted the highest inhibitory on Ch. violaceum while the N-hexane extract exerted the highest growth inhibitory activity on P. mirabilis and Ps. aeruginosa. The extracts compared favorably well with conventional antibiotic (Ciprofloxacin) which is the positive control. The minimal inhibitory concentration (MIC) of all the extracts ranged from 12.5 to 50.0 mg/ml while the minimal bactericidal concentration (MBC) ranged from 25 to 100mg/ml. The analysis of the phytochemicals revealed the presence of tannins, flavonoids, terpenoids, steroids, cardiac glycoside and saponin in all the leaf extracts except for the absence of saponins in N-hexane extract. Conclusion: This study showed that these extracts could be exploited to treat infection caused by these bacterial pathogens. [ABSTRACT FROM AUTHOR]

Background: Throat infections are one of the commonest causes for visits to health care physicians. It was hypothesized that some rare Gram negative bacteria could be implicated in respiratory infections. The molecular dynamics of clinically-significant Gram negative bacteria associated with lower respiratory tract infections was also ascertained. This study investigated the prevalence and antibiotic susceptibility pattern of bacteria associated with throat infections in a hospital setting. Methods: Two hundred and five (205) throat swabs were collected from patients at the study area. Bacterial isolates were identified based on their morphological and biochemical profile. The molecular identity of selected multidrug resistant bacterial isolates was conducted via DNA extraction, polymerase chain reaction (PCR) amplification, sequencing and genome blasting. Antibiotic susceptibility of the test bacterial isolates was evaluated using Kirby-Bauer disc diffusion method. Results: The highest frequency of carriers of throat pathogens was obtained among male patients between ages 31 and 40 years. Streptococcus pneumoniae (28%) had the highest prevalence while Escherichia coli (4%) had the least. One of the enumerated Enterobacter species from the samples was further identified via 16S ribosomal ribose-nucleic acid (rRNA) as Enterobacter bugandensis MH712497.1. Staphylococcus aureus and Streptococcus pyogenes were resistant to gentamicin whilst both Gram-negative bacteria were susceptible to ciprofloxacin at 21.00±0.58 mm and 20.00±0.58 mm respectively. Conclusion: This study deduced that Streptococcus species is most implicated bacteria responsible for throat infections in clinical setting. Molecularly-identified Enterobacter bugandensis from throat infections in this study has recently being implicated as a fresh enterobacteria associated with severe clinically-significant infection. [ABSTRACT FROM AUTHOR]