Glyphosate-based herbicides are often used for the control of weeds grown on agricultural fields or farms. Different health problems have been reported to be associated with the use of glyphosate-based herbicides mainly due to their toxicity level. Thus, finding glyphosate utilizing microorganisms to remediate the glyphosate-based herbicides in the environment is crucial. The culture conditions for maximum utilization of glyphosate by bacterial isolates, Stenotrophomonas maltophilia, Bacillus cereus and Enterobacter aerogenes previously isolated from Ugini stream close to corn fields treated with glyphosate-based herbicide at Ofagbe, Delta State, Nigeria were optimized using mineral salt medium containing glyphosate as carbon source. The varied culture parameters assessed were temperature (30, 37 and 40 oC), pH (5, 6, 7, 8 and 9), initial glyphosate concentration (1, 3, 5, 7 and 9 g/L) and incubation time (2-14 days). Optical density (OD) at 560 nm of the culture was used to estimate cell growth or cell load of the glyphosate utilizing bacteria strains at every 2 days for 14 days. The following optimal conditions were determined: initial pH 9.0, incubation temperature 30 °C, initial concentration of glyphosate (1g/L) and incubation time of 12 days. Of the isolates on the medium containing the herbicide as sole carbon and energy source, Bacillus cereus showed the highest growth level (OD average, 0.127, pH average, 6.26. This was followed by Stenotrophomonas maltophilia (OD average = 0.114, pH average = 6.44) and Enterobacter aerogenes (OD average = 0.100, pH average, 6.56). At the increased of glyphosate in the medium there was decreased in growth of the bacteria. Bacillus cereus, Stenotrophomonas maltophilia and Enterobacter aerogenes indicated a high capacity to be able to degrade glyphosate. It is therefore concluded that the bacteria employed in this research can be recommended for bioremediation of environments contaminated with this chemical and further research should conducted to ascertain the catabolic genes present in these individual glyphosate degrading bacteria.

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The effective use of Ficus sycomorus and Hyphaene theibaica traditionally in treatment of variety of illnesses has been widely reported. The aim of the study was to determine the antimicrobial activities of the leaf extracts of Ficus sycomorus and Hyphaene theibaica on Escherichia coli, Staphylococcus aureus and Candida albicans. Fresh leaves of Ficus sycomorus and Hyphaene theibaica were collected, dried and subjected to ethanolic extraction, and screened for phytochemicals. Five different concentrations of each extract was prepared viz: 200, 160, 120, 80 and 40 mg/mL using distilled water as solvent and tested against Staphylococcus aureus, Escherichia coli and Candida albicans using agar well diffusion method.   Qualitative phytochemical screening revealed that F. sycomorus contained phenol saponins, tannins, flavonoids and steroids while H. theibaica contains Saponin, flavonoids, alkaloid, phenol and steroids. Antimicrobial activity of ethanolic leaf extracts of Ficus sycomorus was observed only against Escherichia coli at 200 mg/mL. While no zones of inhibition were observed against any of the test isolates for ethanolic leaf extracts of Hyphaene theibaica. The minimum inhibitory concentration (MIC) of F. sycomorus extracts on E. coli was 100 mg/mL and the minimum bactericidal concentration (MBC) was 200 mg/mL. The activity of F. sycomorus leaf extract on E. coli being an enteric bacteria, could justify the traditional claims of its use in effective treatment of diarrhea and other stomach complications.

Vernonia amygdalina is a member of the Asteraceae family and a shrub of 2-3m tall with a petiole leaf of about 6mm wide and naturally distributed in many parts of West Africa. It is reported to have several health benefits including antimicrobial efficacy. The study assessed the antimicrobial effects of aqueous and ethanolic extracts of Vernonia amygdalina on clinical isolates of Escherichia coli and Proteus spp. Of the 41 urine samples collected included in this research, 21 clinical samples (urine) were collected from Kwararafa Hospital Wukari while the remaining 20 samples were taken from students of Federal University Wukari. Standard microbiological techniques were employed in this investigation. Extracts of the leaves were made using Ethanol and aqueous procedures. The antimicrobial activity of the extracts was tested using pathogenic isolates of Proteus species and Escherichia coli. It was observed that Escherichia coli were susceptible to both extracts of the leaf in high concentrations. The aqueous extract of the leaf shows moderate growth on the Proteus species but the ethanolic extract of the leaf presented significant antimicrobial activity on Proteus spp. This study has revealed greatly that extracts of Vernonia amygdalina in high concentration possess strong antimicrobial activities against the tested clinical isolates Proteus species and Escherichia coli with ethanolic extract of the leaves exhibiting greater antimicrobial significance against the tested clinical isolates compared to aqueous extracts of the leaves.