This study was aimed at using Balanite aegyptiaca seed coats activated carbon (BAAC) as a potential adsorbent to remove safranin dye from aqueous solution. BAAC was prepared from Balanite aegyptiaca seed coats using a one-step procedure with 67.27% yield, 3.23% ash content, 695 m2/g surface area and 203 mg/g iodine number. The FTIR spectroscopy revealed O-H, N-H, C-H, C=C, C-O-H stretching vibrations. The influences of agitation time, initial dye concentration and adsorbent dose were studied in batch experiments at room temperature. The adsorptions were rapid at the first 15 minutes of agitation, with the uptake of 2.746 mg/kg. The adsorption equilibrium was achieved at 90 minutes of agitation. Kinetic studies showed good correlation coefficient for both pseudo-first order and pseudo-second-order kinetics model but fitted well into pseudo-second order kinetic model. The adsorption data fitted well into Langmuir isotherm with correlation coefficient (R2) very close to unity and Langmuir maximum adsorption constant, qm  1.00. Thus, the fitting into Langmuir indicates monolayer coverage on the adsorbents. The results showed that BAAC has the potential to be applied as alternative low-cost adsorbents in the remediation of dye contamination in wastewater.

Article History KeywordsGreen synthesis Cu/Ni BMNPs Palmyra palm Fruit extract Larvicidal activity Culex quinquefasciatus.The mixture of Cu 2+ /Ni 2+ solution was reduced to Cu/Ni BMNPs using fruit extract of Palmyra palm as a green reducing agent. The formation of Cu/Ni BMNPs noticed based on the visual change in color of the reaction mixture at room temperature from sky-blue to light blue within 15 min. UV-Visible and Fourier Transform Infra Red spectrophotometers were applied to investigate the Optical properties as well as the interaction between the formed Cu/Ni hybrid nanoparticles and the raw fruit extract respectively. These Cu/Ni BMNPs were evaluated for larvicidal potency against first, second and third instars of Culex quinquefasciatus. The larvicidal studies were carriedout at the concentration range of 5-50 mg/L (Cu/Ni BMNPs) and the %mortality increases with increase in concentration for all the instars. The result showed good activity where the lethal concentration values herein for the three instars were LC50=14.75, LC90=83.96; LC50=18.25, LC90=258.83; LC50=18.50, LC90=331.50 mg/L respectively. Therefore, Cu/Ni BMNPs could be a potential future nanolarvicide for Culex quinquefasciatus. Contribution/Originality:The study is one of a very few studies which have investigated fast green synthesis of Cu/Ni bimetallic nanoparticles and its larvicidal activity against larvae of Culex quinquefasciatus.

The complexes of Co (II), Mn (II) and Ni (II) with Schiff base derived from pentane-2, 4-dione and 2-aminobenzoic acid were synthesized and characterized by molar conductivity, magnetic susceptibility, Infrared and elemental analyses. The solubility test on the Schiff base and its metal (II) complexes revealed their solubility in most organic solvents except chloroform and diethyl ether. The molar conductivity of the complexes was small indicating that they are non-electrolytes. The antibacterial susceptibility test conducted on the Schiff base and the metal (II) complexes showed a good activity except Ni (II) complex.

Complexes of Co and Cu with SMZ were successfully synthesized (1:2 molar ratio) in good yield and characterized by using UV-vis, FTIR, melting point/decomposition temperature, electrical conductivity and solubility in different solvents of varying polarity and proticity. All the prepared complexes were coloured. From the IR results, 529, 631, 528 and 779 cm-1 bands were observed in the spectra of the complexes which were absent in the free ligand spectrum thus, showing the presence of metal-ligand bond (coordination) in the complexes. The electronic spectral data of the complexes suggest an octahedral and tetrahedral geometry for all the complexes. The ligand and the Co (II) complex were found to be soluble polar protic solvents at both room and elevated temperature while, Cu (II) complex was found to be insoluble in polar protic solvent (ethanol) at room temperature but soluble at elevated temperature. The metal complexes are insoluble in non-polar solvent at both temperatures. More so, the ligand was found to be soluble in non-polar solvent at both temperatures. The electrical conductivity measurements indicated that the synthesized complexes are non-electrolytes. The synthesized metal complexes showed improved broad-spectrum antimicrobial activity against E. coli and S. aureus as compared to the ligand.  Thus, the complexes [Co(C10H11N3O3S)] and [Cu(C10H11N3O3S)] are good leads to be developed into antibiotics against the tested antimicrobial agents (E. coli and S. aureus).

Plant mediated nanoparticles have been investigated to possess many applications in many fields such as pharmaceuticals, therapeutics and other commercial products. In this study, Copper/Cobalt bimetallic nanoparticles were synthesized by an eco-friendly and cost effective method using Palmyra palm fruit extract and characterized using various techniques such as UV-visible spectrophotometry and Fourier transform infrared spectrometry. Green synthesis method was used in obtaining the nanoparticles and the agar well diffusion method was used in evaluating the larvicidal activity. The resulting nanoparticles were evaluated to find possible application as nanolarvicide against first, second and third instar of Culex quinquefasciatus larvae in terms of percentage mortality. The lethal concentration values were LC50=12.036, LC90=143.316; LC50=14.774, LC90=263,456; LC50=16.076, LC90=296.758 ppm for the first, second, and third instars respectively implying moderate activity of this copper/cobalt nanoparticles. It could be concluded that copper-cobalt bimetallic nanoparticles synthesized using fruit extract of palmyra palm could be a potential nanolarvicide for mosquito larvae management. Contribution/Originality: This study contributes to the existing literature on Copper/Cobalt biological activity for control of mosquitoes in our environment.