Biologija

Title

2026-05-15T11:07:02+03:00

2026-05-15T11:10:05+03:00

Insights into the quality index of surface water from the Okpare Olomu River, Southern Nigeria

2026-05-15T11:45:12+03:00

This study evaluated the physicochemical characteristics, heavy metal contamination, and water quality of the surface water from the Okpare Olomu River in Ughelli South, Delta State, Nigeria. Water samples from four stations were analysed for physicochemical parameters, heavy metals (Fe, Pb, Cd, Cr, Cu, Zn, Mn), and the total hydrocarbon content (THC). The pH ranged from 5.71 to 5.86, indicating slightly acidic water. Electrical conductivity (17.23–24.23 µS/cm), total dissolved solids (6.18–13.46 mg/L), and total suspended solids (71.20–75.20 mg/L) were low, while dissolved oxygen (5.12–6.24 mg/L) and biochemical oxygen demand (3.34–7.43 mg/L) reflected moderate water quality. Heavy metal concentrations followed the order: Fe (0.86–2.35 mg/L) > Pb (0.00–0.23 mg/L) > Cd (0.02–0.07 mg/L) > Cr (0.06–0.12 mg/L) > Cu (0.06–0.09 mg/L) > Zn (0.13–0.16 mg/L) > Mn (0.01–0.02 mg/L), with Fe, Pb, and Cd exceeding the permissible limits established by NESREA, USEPA, and the WHO. THC ranged 2.85–3.62 mg/L. The Water Quality Index (WQI: 136.21–1113.24) classified all stations as Grade E and unsuitable for drinking, while the Comprehensive Pollution Index (CPI: 0.66–2.20) indicated station 2 as severely polluted, stations 1 and 3 as moderately polluted, and station 4 as slightly polluted. Health risk assessment revealed non-carcinogenic risk due to arsenic exposure (HI > 1), and integrated carcinogenic risk suggested a high potential for cancer among consumers. These findings highlight the urgent need for mitigation strategies, continuous monitoring, and public health interventions to reduce heavy metal contamination and protect communities dependent on the Okpare Olomu River.

Antimicrobial activity of ethanolic and aqueous extracts of Urtica dioica, Mentha piperita, Plantago lanceolata and Cynara scolymus leaves

2026-05-15T11:45:11+03:00

Natural antimicrobial agents, particularly plant extracts from Urtica dioica, Mentha piperita, Plantago lanceolata and Cynara scolymus, have attracted considerable attention due to their broad biological activity driven by diverse bioactive compounds and synergistic effects. The efficacy of these extracts depends on plant species, chemical composition, extraction method, and solvent, emphasizing the need for systematic evaluation of ethanolic and aqueous extracts as potential alternatives to synthetic antimicrobials. The aim of this study was to determine and compare the antimicrobial activity of ethanolic and aqueous leaf extracts of Urtica dioica, Mentha piperita, Plantago lanceolata and Cynara scolymus. Reliability was ensured through triplicate testing and standardised methodology (well diffusion method, 100 mg/ml concentration), confirming that the results are representative and statistically valid. Findings indicate that ethanolic extracts demonstrated significantly stronger antimicrobial activity than aqueous extracts (p < 0.05), particularly against Gram-positive bacteria (Staphylococcus epidermidis, Bacillus cereus, Enterococcus faecalis) and the fungus Candida albicans, while Gram-negative bacteria (Salmonella enteritidis, Yersinia enterocolitica) were largely resistant except Pseudomonas aeruginosa. Mentha piperita and P. lanceolate ethanolic extracts exhibited the broadest and most potent antimicrobial spectrum, U. dioica and C. scolymus leaves showed weaker activity but remain valuable sources of bioactive compounds.

Academician Sofija Kanopkaitė: A Centenary of Her Birth (3 March 1926–16 March 2024)

2026-05-15T17:35:10+03:00

Abstracts of the 18th Rodens et Spatium – International Conference on Rodent Biology