Revista de Ciencias Químicas

Synthesis and characterization of organic ligand N-(2-chloro phenyl)-N’ benzenesulfonyl thiourea (H₂L¹) was described. The formed ligand incorporated several potential donor sites, making it a versatile complexing agent with metal ions due to the presence of the sulfonyl and thiourea groups, each solely may act as a key constituent of many biologically active species. In this work, we present the synthesis of Pt (II), Pd (II) and Au (III) metal complexes and their coordination behavior towards the unsymmetrical organic ligand (H₂L¹) using microwave-assisted irradiation. The microwave approach provides clean, shorter reaction times and enhancements in yields. The prepared metal complexes have been characterized by elemental analysis, FT-IR, 1HNMR, UV-Vis, thermal analysis and magnetic susceptibility. They were tested for their antibacterial activity against Gram positive, Gram-negative bacteria as well as fungi. Also anti-cancer assay was applied against two cell lines; breast cancer cells (MCF-7) and liver cancer cells (HepG-2). The IR spectral data indicate that the ligand H₂L¹ coordinates to metal ions through sulfonyl and thionyl groups in a tetradentate square planer manner for PdII and PtII ions while in case of AuIII it takes an octahedral shape. Based on spectrophotometric investigations, it is suggested that Pd(II), Pt(II) and Au (III) form 1:1 complexes. The molecular compositions of the complexes were proposed on the basis of chemical analyses and spectrophotometric evidences.

This study involves the physiochemical, microbiological and selected heavy metals variations of palm oil samples sourced from galadima, tarauni, yan-kura markets of kano state and samples from Kogi and Edo States of Nigeria. The samples were evaluated using standard documented procedures. The result showed; samples from Edo had: oil acid value 0.73 ± 0.13, iodine value 29.25 ± 0.09, peroxides value 2.68 ± 0.09, saponification value 194.31 ± 2.21, moisture content 1.13 ± 0.56, ester value 195.04 ± 2.08. The samples from Kogi had; acid value 0.88 ± 0.11, iodine value 11.54 ± 0.24, peroxides value 5.79 ± 0.62, saponification value 187.49 ± 0.56, moisture content 1.60 ± 0.10, ester value 186.61 ± 0.45. The sabon-gari samples had; oil acid value 0.86 ± 0.17, iodine value 30.37 ± 0.34, peroxides value 3.25 ± 0.95, saponification value 188.66 ± 1.88, moisture content 1.19 ± 0.59, ester value 187.8 ± 1.71. Galadima samples had: acid value 0.89 ± 0.14, iodine value 29.31 ± 0.47, peroxides value 6.8 ± 0.16, saponification value 182.62 ± 3.65, moisture content 1.82 ± 0.67, ester value 181.73 ± 3.5. Taruani samples had; acid value 0.56 ± 0.13, iodine value 29.63 ± 0.81, peroxides value 5.79 ± 0.62, saponification value 194.07 ± 0.47, moisture content 1.43 ± 0.71, ester value 193.51 ± 0.44. Yan-kura samples had: acid value 0.98 ± 0.09, iodine value 30.78 ± 0.26, and peroxides value 6.2 ± 0.14, and saponification value 184.045.00, and moisture content 1 21 ± 0.60, ester value 183.06 ± 4.91. The microbiological analysis of the samples revealed sabon-gari samples had 1.0 × 10^-5, galadima 7.6 × 10^-3, Tarauni 7.2 × 10^-4, Kogi 1.2 × 10^-5, Yan-kura 1.1 × 10^-5 and Edo 6.8 × 10^-3 cfu/ml respectively. The heavy metals analysed were cadmium (Cd), arsenic (As), mercury (Hg) and lead (Pb). The concentrations of Cd ranged between 0.001 (ppm) Tarauni to 0.019 (ppm) Galadima, As (ppm) ranged between 0.01 Edo and Kogi to 0.047. Hg (ppm) 0.01 Edo to 0.19 galadima and Pb (ppm) 0.05 Kogi to 0.18 galadima. From the results obtained, it shows that Yan-kura has the most polluted oil due to the exposure to the environment. The samples collected are safe for consumption as at time of analysis, however continuous monitoring is required.