Synthesis, Characterization and Antimicrobial Activity of Cu (II), Co (II) and Ni (II) Histidine Complexes

Ternary complexes of histidine amino acid (Schiff base) were synthesized, characterized and tested against multi-drug resistant pathogens. The metal ion centers included Cu (II), Ni (II) and Co (II). These complexes were characterized using physico-chemical and spectroscopic analytical methods. All the complexes are found to be considerably soluble in both polar and non-polar solvents including methanol, ethanol, butanol, acetone, ethyl acetate, and benzene and di ethyl-ether. Electronic Absorption Studies using FT-IR spectrophotometer revealed ν (O-H), ν (C=O), ν (C=N), ν (M -N) and ν (M-O) occurred between 3410 - 3417, 1751 - 1753, 1519 – 1521, 671 – 678, 439 – 470 cm-1 respectively in complexes and ligand. UV-Visible was further used to elucidate the complexes resulting in transitions characteristics of the ligand and complexes. The Schiff base showed no antimicrobial activity at various therapeutic concentrations. However, the metal complexes exhibited broad spectrum antibiotic activities against the multi-drug resistant pathogens at minimum inhibitory concentration (MIC ≤ 200 µg/ml). The metal complexes showed strong activity against the isolates at medium and high concentrations, the bacteria strains included E.coli, P. aeruginosa, S. typhi and S. aureus and the fungi strains of Candida albicans, Aspergillus flavus and Aspergillus niger. The bioactivity recorded against these multi drug resistant pathogens indicates the potentials of these complexes for further therapeutic studies. Keywords: Histidine complex, synthesis, characterisation, antimicrobial activity, pathogens

Heavy Metals Contamination in Roadside Dust along Major Traffic Roads in Jos Metropolitan Area, Nigeria

Heavy metal concentration in roadside dusts are increasingly becoming of health concern.  Five major traffic roadside dust were determined for Cu, Pb, Ni, Zn, Fe, Cd, Mn and Cr contamination. Metal concentration in the dusts indicated Cu concentration ranged from    24.5 – 67.0 mg/kg, Pb 25.0 – 66 mg/kg, Ni 1.23 – 3.88 mg/kg, Zn 35.0 – 123 mg/kg, Fe 48.5 – 125 mg/kg, Cd 1.54 – 2.58 mg/kg, Mn 1.15 – 2.58 mg/kg and Cr 1.13 – 2.79 mg/kg. The accumulation of the heavy metals in the soil dust is greatly influenced by traffic volume and the metals exhibited a significant reduction in roadside dust with increasing distance from the road. Four methods of assessing pollution were used to assess the extent of pollution. All the four methods revealed that site ABW, YGW and GJR are pollution impacted as compared MMW and BRR sites. The result suggest mixed origin of pollution sources including human activities, vehicular emissions and lithogenic occurrences of the metals from road construction currently in some of the sites studied. The findings herein will serve to create awareness of vehicular heavy metal pollution  and therefore suggest a regular monitoring to ensure suitable management of the urban environment and reduction of traffic related contamination of soil, plants and water in Jos Nigeria. Keywords: Roadside Soil Dust; Heavy Metals Contamination; Enrichment Factor;    contamination Factor; Pollution Load Index; Geoaccumulation Index; Statistical Analysis

Heavy Metals in Soil and Vegetables Irrigated with Ex- Tin Mining Ponds Water in Barkin - Ladi Local Government Area Plateau State, Nigeria

Tin mining pond water irrigated fields can cause potential contamination with heavy metals to soil and vegetables, thus pose a threat to human beings. The current study was designed to investigate the contamination of the soil with toxic heavy metals and their accumulation in edible vegetable crops. The heavy metals Pb, Cu, Cd, Zn, Cr, Fe, Mn and As were analyzed for their bioaccumulation factors to provide baseline data regarding environmental safety and the suitability of tin mining pond water for irrigation in the future. The contamination factor (CF) of these metals in the soil were calculated and indicated levels of metal contamination in the order of Cd > Zn > Pb > Cr > Cu > As ˃ Fe ˃ Mn. The concentrations of Pb, Cd, Cr, As, and Mn in the edible vegetables were above the safe limit prescribe by FAO/WHO, 2007 and EU, 2002 in all studied vegetables. The results indicated a potential pathway of human exposure to slow poisoning by heavy metals due to the utilization of vegetables grown on heavy metal contaminated soil that was irrigated with tin mining pond water sources. Amongst the studied vegetables, As and Cr were observed to exceeds tolerable limit. The irrigation source was identified as the source of the soil pollution in this study. Thus, their consumption might pose substantial health risk to consumers and therefore need for proper remediation to reduce health risk and the extent of heavy metals contamination

Relationship between urban planning and flooding in Port Harcourt city, Nigeria; insights from planning professionals

Flooding is widely recognised as a global problem which has worsened in recent years due to climate change. In Nigeria, flooding remains the most widespread environmental disaster with the population of 200 million suffering numerous threats from perennial flooding. Port Harcourt in Southern Nigeria experiences annual flooding on a significant scale. While research has linked the flooding in Port Harcourt to poor urban planning, little research has engaged with planning professionals to investigate this relationship. This paper fills this gap. It explores how urban planning is linked to flooding in Port Harcourt and reports on qualitative research undertaken with five urban planners in Port Harcourt. The findings affirm that poor planning and/or lack of compliance with planning regulations are the main factors contributing to the flooding of Port Harcourt. The urban planners gave their expert opinions on how to control the flooding and unanimously agreed that improved planning practices could control the endemic flooding problem in the city. This implies that the government needs to work more closely with urban planners and other stakeholders to effectively control and find a lasting solution to the flooding problem in Port Harcourt city