RESUMEN
Anthropogenic activities around the sea ports are capable of causing changes on the physicochemical and microbiological quality of water bodies along the port terminals. Such activities can cause an ecological imbalance in the water quality /ecosystem resulting in extinction of aquatic resources. The aim of this study therefore was to investigate the physicochemical and microbiological quality of surface water along the busy port terminals. Surface water samples were collected from Onne port terminal using sterile containers. The samples were collected during the wet and dry seasons between January to June 2021. The sterile bottles were filled with surface water samples and transported in an ice packed container to the Department of Microbiology Laboratory of the Rivers State University for analyses using standard analytical methods. Statistical analyses were carried out using ANOVA and All pairs tukey-kramer. Results of the physicochemical parameters showed that temperature, total dissolved solids, total suspended solids, nitrate and heavy metals were significantly higher during the dry season than the wet season at P ? 0.05 levels of significance. Seasonal variation with respect to microbial counts shows that Total Heterotrophic Bacteria, Total Heterotrophic Fungi, Total coliforms and Faecal coliforms had a mean value of 3.9±1.77 x 106; 0.8 ±0.05 x 104 ; 7.4 ±1.3 x 104 and 3.6 ±0.17 x 104 colony forming unit per millilitre respectively for wet season while the dry season had 1.6±0.77 x 106 , 0.5 ±0.01 x 104 , 4.6 ±0.17 x 104 and 2.7 ±1.03 x 104 cfu/ml respectively. In this study, the predominant bacterial isolates belonged to the genera of Vibrio, Pseudomonas, Klebsiella, Bacillus, Shigella, Staphylococcus, Salmonella, Proteus, Bacillus and Escherichia. coli. The results of physicochemical and microbiological characteristics including the heavy metals, were detected at concentrations on or below detection limits.. It is therefore suggested that relevant environmental regulatory bodies should maintain regular check to ensure that appropriate standards are maintained around seaports due to beehive of activities.
RESUMEN
Aim: This study was carried out to investigate the antibacterial properties and efficacy of mango (Mangifera indica) leaf extracts on some clinical isolates as test rganisms. Study Design: The study employed statistical analysis of the data and interpretationPlace and Duration of Study: Young and mature mango leaves were collected from the Botanical Garden, Kenule Beeson Saro-Wiwa Polytechnic, Bori, Nigeria, and taken to the laboratory for analyses. Methodology: The samples were dried in an oven at 80oC for 3 days. Thereafter, 50 g of each ground mango leaf (young and mature leaves) were soaked separately in 500 ml of water, ethanol (95% v/v), and acetic acid (99.9% v/v) respectively for another 3 days. The soaked materials were filtered through Whatman No. 1 filter paper into sterile beakers and evaporated to dryness in a water bath at 80oC. The dried extracts obtained were reconstituted with water at concentrations of 100, 75, 50, and 25 mg/ml. Test organisms, Escherichia coli, Staphylococcus aureus, Salmonella typhi, Proteus mirabilis, Bacillus cereus, and Pseudomonas aeruginosa were obtained after proper laboratory screening of isolates from the diagnostic laboratory of the Rivers State University Teaching Hospital, Port Harcourt, Nigeria, for confirmation of identity and storage in universal bottles in a refrigerator. Sensitivity tests were carried out with the agar well diffusion method against the test organisms, using tetracycline as the standard control drug, with cultures incubated accordingly. The measured zones of inhibition were compared with the controls and interpreted as resistant, intermediate, or susceptible to mango extracts in accordance with the interpretive guidelines published by the National Committee for Clinical Laboratory Standards (NCCLS). Assay for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was also carried out. Results: Results obtained showed that acetic acid young leaf extract at 100mg/ml produced 50 % susceptibility and 50 % intermediate response of test bacterial species. Generally, at 100 mg/ml, acetic acid young leaf extracts yielded 50% susceptibility and 50% intermediate response among both Gram-positive and Gram-negative bacteria. Ethanolic extracts gave 100% intermediate sensitivity of Gram-negative species and 50% each of resistant and intermediate response in Gram-positive forms. Aqueous extracts also produced no susceptibility among the test organisms as there was 100% resistance. Extracts of mature mango leaves of all solvents and at all concentrations used yielded no susceptibility response among the test bacterial species on the NCCLS scale. Minimum inhibitory and bactericidal concentrations were found to range from 25 mg/ml to 50 mg/ml. Additionally, it was observed that the sensitivity of organisms to mango extracts increased with concentration.Conclusion: In conclusion, acetic acid has a better extracting potential than ethanol and water as a solvent for the extraction of mango parts. More so, young mango leaves extracted with acetic acid possess higher broad-spectrum antibacterial properties than the mature mango leaves extracted from the same plant. It is therefore recommended that young mango leaves, extracted with acetic acid, be used for the treatment of microbial infections at concentrations not below 50 mg/ml.