BackgroundFollowing claims that some plants have antimicrobial activities against infectious microbes, the in vitro antimicrobial activities of different solvent fractions of ethanolic extract of Cryptolepis sanguinolenta were evaluated against eight standard bacteria and clinical isolates.MethodsThe solvent partitioning protocol involving ethanol, petroleum ether, chloroform, ethyl acetate and water, was used to extract various fractions of dried pulverized Cryptolepis sanguinolenta roots. Qualitative phyto-constituents screening was performed on the ethanol extract, chloroform fraction and the water fraction. The Kirby Bauer disk diffusion method was employed to ascertain the antibiogram of the test organisms while the agar diffusion method was used to investigate the antimicrobial properties of the crude plant extracts. The microplate dilution method aided in finding the MICs while the MBCs were obtained by the method of Nester and friends. The SPSS 16.0 version was used to analyze the percentages of inhibitions and bactericidal activities.ResultsThe phytochemical screening revealed the presence of alkaloids, reducing sugars, polyuronides, anthocyanosides and triterpenes. The ethanol extract inhibited 5 out of 8 (62.5%) of the standard organisms and 6 out of 8 (75%) clinical isolates. The petroleum ether fraction inhibited 4 out of 8 (50%) of the standard microbes and 1 out of 8 (12.5%) clinical isolates. It was also observed that the chloroform fraction inhibited the growth of all the organisms (100%). Average inhibition zones of 14.0 ± 1.0 mm to 24.67 ± 0.58 mm was seen in the ethyl acetate fraction which halted the growth of 3 (37.5%) of the standard organisms. Inhibition of 7 (87.5%) of standard strains and 6 (75%) of clinical isolates were observed in the water fraction. The chloroform fraction exhibited bactericidal activity against all the test organisms while the remaining fractions showed varying degrees of bacteriostatic activity.ConclusionThe study confirmed that fractions of Cryptolepis sanguinolenta have antimicrobial activity. The chloroform fraction had the highest activity, followed by water, ethanol, petroleum ether and ethyl acetate respectively. Only the chloroform fraction exhibited bactericidal activity and further investigations are needed to ascertain its safety and prospects of drug development.

Aims: The purpose of this study was to investigate the antibiotic resistance and clonal lineage of serogroup B Salmonella isolated from patients suspected of suffering from enteric fever in Accra, Ghana. Methods and Results: Serogroup B Salmonella were isolated from blood (n ¼ 28), cerebral spinal fluid (CSF) (n ¼ 1), or urine (n ¼ 2), and identified based on standard biochemical testing and agglutinating antisera. Isolates were examined for their susceptibility to ampicillin, chloramphenicol, tetracycline and trimethoprim-sulfamethoxazole. Most of the isolates could be classified as multiple-drug resistant. Furthermore, the genetic location of resistance genes was shown to be on conjugative plasmids. Genetic fingerprinting by plasmid profiling, enterobacterial repetitive intergenic consensus (ERIC)-PCR, and repetitive element (REP)-PCR were performed to determine the diversity among the isolates. Plasmid profiling discriminated five unique groupings, while ERIC-PCR and REP-PCR resulted in two and three groupings, respectively. Conclusions: A high rate of antibiotic resistance was associated with the Salmonella isolates and the genes responsible for the resistance are located on conjugative plasmids. Also, there appears to be minimal diversity associated with the isolates. Significance and Impact of the Study: As a result of the increasing antibiotic resistance among bacteria of all genera, surveys to monitor microbial populations are critical to determine the extent of the problem. The inability to treat many infectious diseases with current antibiotic regimens should prompt the medical community to be more prudent with its antibiotic use.

Fungal pathogens continue to pose challenges to humans and plants despite efforts to control them. Two coumarins, robustic acid and thonningine-C isolated from Millettia thonningii, show promising activity against the fungus Candida albicans with minimum fungicidal concentration of 1.0 and 0.5 mg/mL, respectively. Molecular modelling against the putative bio-molecular target, lanosterol 14α-demethylase (CYP51), revealed a plausible binding mode for the active compounds, in which the hydroxyl group binds with a methionine backbone carboxylic group blocking access to the iron catalytic site. This binding disrupts the synthesis of several important sterols for the survival of fungi.

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The presence of pharmaceuticals in the environment is undesirable since their biological activity may impair ecosystem health of reservoirs that receive inflows from other water sources. This work determined the concentrations of analgesics and antibiotics, and the occurrence of antimicrobial resistance among microbes in water and sediment samples from Owabi and Barekese reservoirs—two main sources of pipe-borne water in the Kumasi metropolis in Ghana. The study also assessed the knowledge, attitude, and practice of inhabitants near these reservoirs regarding the disposal of unused and expired medicines. Out of nine targeted pharmaceuticals, four were detected in at least one sample. Five analytes (caffeine, ciprofloxacin, doxycycline, ibuprofen, and metronidazole) were below detection limit for all samples. The levels of pharmaceuticals were low, as expected, ranging from 0.06 to 36.51 μg/L in the water samples and 3.34–4.80 μg/kg in sediments. The highest detected concentration of any pharmaceutical in water was for diclofenac (107.87 μg/L), followed by metronidazole (22.23 μg/L), amoxicillin (1.86 μg/L), chloramphenicol (0.85 μg/L), and paracetamol (0.16 μg/L). Chloramphenicol recorded the highest concentration (10.22 μg/kg) in the sediments. Five bacteria isolates (Enterobacter, Clostridium, Pseudomonas, Acinetobacter, and Klebsiella) from the samples were resistant to all the antibiotics tested. Isolates of Corynebacterium and Listeria showed susceptibility to only doxycycline. Isolates of Bacillus were susceptible to only two antibiotics (erythromycin and doxycycline). All the 100 respondents interviewed admitted that they dispose of medications once they do not need them. Of those who disposed of unwanted medicines, 79% did so inappropriately. Disposal in household trash (67%) was the most common method used. Majority of respondents felt the need for a facility or program to collect unused medicines (77%), hence their willingness to pay to reduce pollution by pharmaceuticals in the environment. It is quite clear from the ecotoxicological risk assessment that a single pharmaceutical at very low level as those in this study and other works is likely to pose many ecological risks upon long-term exposure and therefore cannot be ignored.

The study investigated the influence of Annona muricata extracts on the action of selected antibiotics against biofilm-forming MRSA. The various parts of the plant were processed into powder and extracted with ethanol or hot water and then screened for the presence of phytochemicals. The modulatory effect of the Annona muricata extract was also tested on some antibiotics against Methicillin-resistant Staphylococcus aureus (MRSA). The findings from this study revealed that the various parts of the Annona muricata extract (ethanolic and aqueous) contained different proportions of secondary metabolites. Varied antimicrobial activities were observed when the extract of the A. muricata was exposed to MRSA strain at a concentration of 100 mg/mL. The stem recorded the highest (17.00 and 18.00 mm) inhibitory activity against MRSA for both the aqueous and the ethanolic extract, respectively, and this was not different from the control, tetracycline. Again, the results on the modulatory action indicated that out of the 10 extracts of A. muricata, 4 of them antagonized the activity of ampicillin against the tested MRSA by a factor of 0.5 folds and the rest potentiated the drug within 1–4 folds, respectively. On the other hand, the various test extracts significantly potentiated the efficacy of streptomycin and tetracycline against the MRSA by a range of 1–32 folds with the aqueous root extract recording the highest synergistic effect and ethanol seed extract with the least effect. The findings of this study support the antibacterial activities of the A. muricata plant parts.

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