Open Access Original Research Article

Application of Substituent Electronic Descriptors QSAR Model of 2-amino-6-arylsulfonylbenzonitriles as HIV-1 Reverse Transcriptase Inhibitors based on the MOLMAP Approach

Razieh Sabet, Maryam Sabet

Asian Journal of Applied Chemistry Research, Page 1-11
DOI: 10.9734/ajacr/2018/v1i29617

The HIV-1 reverse transcriptase (RT) is a major target for drug development. Inhibition of this enzyme has been one of the primary therapeutic strategies in suppressing the replication of HIV-1. A series of 2-amino-6-arylsulfonylbenzonitrile derivatives were subjected to quantitative structure-activity relationship (QSAR) analysis. Very recently, we proposed the use of substituent electronic descriptors (SED) instead of the electronic descriptors of whole molecules as new and expedite source of electronic descriptors. In this study, we used SED parameters in QSAR modeling of anti HIV-1 activity of 6-arylsulfonylbenzonitrile derivatives. In SED methodology produces a vector of electronic descriptors for each substituent and thus a matrix of SED is generated for each molecule. Consequently, a three-dimensional array is obtained by staking the data matrices of different molecules beside each other. As a novel multiway data analysis method, molecular maps of atom-level properties (MOLMAP) approach was also used to transfer a three-dimensional array of SED descriptors into new two-dimensional parameters using Kohonen network, following by genetic algorithm-based partial least square(GA-PLS) to connect a quantitative relationship between the Kohonen scores and biological activity.In unfolding data, HOMO1, HOMOB1, SOFB1 and EPHA4 represent the most important indices on QSAR equation derived by PLS analysis. Accurate QSAR models were obtained by both approaches. The resulted GA-PLS model of MOLMAP approach possessed high statistical quality r2= 0.83 and q2=0.70. It could explain and predict about 70% of variances in the anti-HIV1 inhibitory activity of the studied molecules. However, the superiority of three-way analysis of SED parameters based on MOLMAP approach with respect to simple unfolding was obtained.

Open Access Original Research Article

Pollution Status of Heavy Metals in Spent Oil-Contaminated Soil in Gwagwalada

Chinenye Nna Orji, Funke Wosilat Abdulrahman, Nnennaya Rosemary Isu

Asian Journal of Applied Chemistry Research, Page 1-10
DOI: 10.9734/ajacr/2018/v1i29623

The pollution status of some selected heavy metals namely: Pb, Fe, Zn, Cu, Cr, Ni and Cd, in spent oil-contaminated soil were investigated. The soil samples were obtained from different spots of the automobile mechanic workshop, wet digested and the concentrations of the heavy metals in the soil digest determined using Atomic Absorption Spectrophotometer (AAS). The concentration of Pb was significantly higher (p<0.05) than the concentrations of each of the other six heavy metals while cadmium had the least concentration. In most of the sampling spots analyzed, the concentrations Cd were below the detection limit of the instrument used. The order of the concentrations of the heavy metals were Pb> Fe> Zn> Cu> Cr> Ni> Cd and Fe > Cr > Zn> Pb> Cu> Ni> Cd for the spent oil-contaminated and control soils respectively. The concentration of iron, cadmium, copper, nickel and zinc in the control soil were significantly lower (p<0.05) than the concentration of iron, zinc and lead in the oil-contaminated soil. The concentration of Pb exceeded the limits of both the background and intervention lead value set by DPR (Department of Petroleum Resources) of Nigeria. The contamination and potential ecological factors of Zn, Cu, Fe, Cr and Cd were categorized low except Pb which was categorized as having very high contamination factor and moderate potential ecological risk factor. The entire studied spots showed moderate degree of contamination. The potential risk index of the heavy metals ranged from 44.23 to 51.91, which had a low grade category; implying that the heavy metals have caused low harm to the soil of the workshop. This paper gives information on the present status of heavy metals in the soil and the need for continuous monitoring so as to avert further contamination of this workshop.

Open Access Original Research Article

Assessment of Heavy Metal and Selenium Levels in Leachates and Soils of Central Bank of Nigeria Dumpsite Makurdi

Aka J. Egwumah, Ishaq S. Eneji, Raymond A. Wuana

Asian Journal of Applied Chemistry Research, Page 1-12
DOI: 10.9734/ajacr/2018/v1i29627

Leachates from dumpsite basically contain a wide range of heavy metals and selenium. However, heavy metals have negative public health and environmental impacts once the leachates are allowed to infiltrate into groundwater. This is one of the oldest, growing problems threatening the surrounding globally. Therefore, it is imperative to quantify the information on the environmental impact of heavy metal and selenium levels, and suggesting various techniques that could be used to clean-up their concentrations from the environment to the minimum to ameliorate the plight of the people. The aim of this study was to determine the concentration of heavy metal and selenium levels in leachate of Central Bank of Nigeria dumpsite along University of Agriculture Road-Makurdi and also to investigate their levels in soil around the dumpsite platform. The concentrations of some heavy metals such as Chromium (Cr), Lead (Pb), Cadmium (Cd), Mercury (Hg) and non metal Selenium (Se) levels in leachate from Central Bank of Nigeria Dumpsite platform and surrounding soil along University of Agriculture road, Makurdi, were determined using Atomic absorption spectrophotometry (Flame AAS) for Cr, Pb and Cd while cold vapour and hydride generation were used for Hg and Se respectively. The soil samples were collected at different depths (cm) 0 – 20, 20 – 40, 40 – 60 and 60 – 80. The levels of all heavy metals and non metal selenium in this study area were found to be higher than those of the control samples. The total mean concentration of the soil samples analysed for each metal and selenium levels at different depths range from Cr (74.7 – 2.6 mg/kg), Cd (7.41 – 0.6 mg/kg), Hg (4.45 – 1.4 mg/kg), Se (2.04 – 1.2 mg/kg) and Pb (8.53 – 1.7 mg/kg). The concentrations in leachates were Cr (0.079 mg/L), Cd (0.010 mg/L), but Pb, Hg and Se were not detected. The concentrations of Cr and Cd determined in leachate were below the WHO standard limits. Similarly, the concentrations of Pb, Hg and Se in soil analyzed in this study were within the permissible limits. However, the concentration of Cr and Cd were found to be higher than the permissible limits due to the increasing anthropogenic activities in the area. Awareness of the level of soil and leachate pollution around the dumpsite needs to be created urgently especially among people living in the environment. Proper and effective waste management plan should be developed and implemented.

Open Access Original Research Article

Rice Straw and Rice Straw Ash for the Removal of Brilliant Green Dye from Wastewater

Ghadir A. El-Chaghaby, Eman S. Ramis, Abeer F. Ahmad

Asian Journal of Applied Chemistry Research, Page 1-9
DOI: 10.9734/ajacr/2018/v1i29633

Aims: The use of economical, simply obtained and green adsorbents has been employed as a perfect alternative to the expensive methods of removing dyes from aqueous solution. The capability of rice straw and rice straw ash to remove brilliant green dye by the adsorption process has been studied.

Study Design: Adsorption studies were carried out at different initial dye concentrations, contact time and adsorbent dosages.

Place and Duration of Study: Regional center for food and feed, Agricultural research center.

Methodology: Adsorption data were modeled using Langmuir, Freundlich, Temkin adsorption isotherms.

Results: Freundlich model showed the best fit with the equilibrium data for rice straw; however Langmuir model was better fitted for rice straw ash. Kinetic adsorption records were modeled using pseudo-first-order and pseudo-second-order. It was found that pseudo-second-order was best fit with the equilibrium data. Rice straw and rice straw ash were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM).

Conclusion: Rice straw as an agriculture waste by-product could be used as an alternative to commercial activated carbon as adsorbent due to its availability, removal efficiency and low cost.

Open Access Original Research Article

Theoretical Study of the Reaction of Formation of Some Free Phosphines by Stereoselective Hydrophosphination through DFT Method

Kouadio Valery Bohoussou, Anoubilé Bénié, Mamadou Guy-Richard Koné, N’guessan Yao Silvère Diki, Kafoumba Bamba, Nahossé Ziao

Asian Journal of Applied Chemistry Research, Page 1-10
DOI: 10.9734/ajacr/2018/v1i29638

In this work the formation of vinylphosphines was studied through the hydrophosphination reaction. The study aims to rationalize the stereoselectivity of these compounds using quantum DFT methods. This theoretical study of chemical reactivity was conducted at B3LYP/6-311 + G (d, p) level. Global chemical reactivity descriptors, stationary point energies and activation barriers were examined to foretell the relative stability of the stereoisomers formed. The various results obtained have revealed that the addition of arylphosphine to dihalogenoacetylene is stereospecific. The Trans form of vinylphosphines is more stable than the Cis form, when the substituent on phosphorus generates less or no π-conjugations. On the other hand, the Cis isomer is predominant when the aryl radical favors more π-conjugations. The theoretical results obtained are in agreement with the experimental results.