Volume 9

Metal Complexes of (E)–N1-(2-hydroxybenzylidene)nicotine hydrazid Schiff Base; Synthesis, Characterisation and Nematicidal Activity, M. U. Adaji, R. A. Wuana, A. U. Itodo, I. S. Eneji, and M. S. Iorungwa, Arab. J. Chem. Environ. Res. 09(1) (2022) 1-27

Abstract
Complexes of Co(II) and Mn(II)were prepared from tridentate Schiff base, (E) – N1- (2-hydroxybenzylidene)nicotinohydrazide. The Schiff base ligand was synthesisedfrom nicotinicacid hydrazide and salicylaldehyde. These metal complexes were characterised byelemental analysis, molar conductivity, magnetic susceptibility, thermalanalysis, x- ray diffraction, FTIR and UV – visible. The analytical data ofthese metal complexes showed metal: ligand ratio (1:2). The physicochemicalstudy supports the presence of octahedral geometry in all the complexes. The IRspectral data reveal that the ligand behaves as tridentate with ON donor atomsequence towards central metal ion. The molar conductivity values of the metalcomplexes suggest their non electrolytic nature. The x ray diffraction datasuggests orthorhombic crystal system for these complexes. Thermal behaviour(TGA/DTA) described the general decomposition patterns of the complexes. Theligand and its complexes were screened for their nematicidal activity and theresults show that the complexes exhibit promising nematicidal activity. Theresults reveal that the metal complexes are more potent nematicides than theSchiff base ligand.

Evaluation of total soluble fluoride concentration in some selected toothpastes in Nigeria, U. S. Oma, Y. Abdulrazak, A. M. Umar, A. D. Joseph, G. T. Buluku, O. Ajifa, Arab. J. Chem. Environ. Res. 09(1) (2022) 28-37

Abstract
Dental caries remains the most prevalent chronic disease of kids in the world. Fluoride has shown effectiveness in the prevention of caries and giving maximum protection against dental caries while reducing the likelihood of enamel fluorosis. Fluoride is most effective in dental caries prevention when a low level of fluoride is constantly maintained in the oral cavity. Meanwhile, there are some undesirable side effects of too much fluoride exposure. This research involves the determination of the total soluble fluoride concentration of five brands of fluoridated toothpastes using ion-selective electrode (ISE). The different brand of adult toothpastes was purchased from local market/shops in Anyigba, Kogi State. Four of the samples contain sodium fluoride as active ingredient while one of them contains sodium monofluorophosphate. The total soluble fluoride content found for the various samples are as follows; sample A and B 0.066%; C: 0.05%; D: 0.138%; and sample E: 0.101% which are approximately 0.1 % (1000ppm) and 0.14%(1400ppm). These results fell within the standard given by the World Health Organization (WHO) and other agencies

Extraction selectivity: A novel tool for green process development and design of solid-liquid extractor, U. A. Isah, L. S. Chua and R. Abdul-Aziz, Arab. J. Chem. Environ. Res. 09(1) (2022) 38-66

Abstract
In process synthesis, design, and optimization of solid-liquid extractor, extraction yield (EY) has been the only process parameter used for centuries in determining the process performance. Solid-liquid extraction (SLE) is one of the crucial units in phytochemical processing. This communication introduces a concept of extraction selectivity (ES) as a new tool for green process analysis, design and development of solid-liquid extractor that overcomes the limitations of EY. New and simple equations have been developed based on the fundamental concepts of physical sciences, chemical, and process engineering. In addition, it proposes new schemes for the green SLE based on the concept of multiple extractions analogous to multiple reactions. Some of the equations were employed in the analysis of green SLE of andrographolide water extract and other phytochemical compounds from Andrographis paniculata (AP) as a case study. It was found that the performance indicator, ES is more sensitive and pronounced to changes in the process variables of SLE than EY. .