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Chemical Studies of Tephrosia vogelii and Commiphora schimperi Occurring in Ethiopia
Tegene Tesfaye Tole,
Belay Akino Neme
Issue:
Volume 7, Issue 3, September 2019
Pages:
45-53
Received:
16 July 2019
Accepted:
4 September 2019
Published:
19 September 2019
Abstract: The objective of this study is to extract, screen, isolate, and characterize the chemical constituents of Tephrosia vogelii and Commiphora schimperi. In the course of this study the stem bark of T. vogelii and resin of C. schimperi were collected from Areka Agricultural Research institute, Wolaita Zone and Konso, Gamo Gofa Zone, respectively. Phytochemical screening of the crude extract of T. vogelii revealed the presence of tannins, saponins, flavonoids, and terpenoids. Chromatographic separation of the methanolic crude extract of T. vogelii yielded the compound 8 (4, 5-dihydro-5, 5-dimethyl-4-oxofuran-3yl)-5-hydoxy-7-methoxy-2-phenyl-4H-chrome-4-one. The essential oil from the resin of C. schimperi was isolated by hydro-distillation and some of the components identified by means of GC and GC/MS analysis. The main components of the essential oil from C. schimperi were: α-pinene (73%) and β-pinene (17%). The resin was also subjected to extraction by petrol, ethyl acetate, and methanol. The components of C. schimperi were isolated using chromatographic techniques and attempts were made to identify the isolated substances. Analysis of the petrol extract of the resin of C. schimperi showed to be an excellent source of the industrially important fragrant compounds, α- and β-pinene. The structures of the isolated compounds were characterized by comparing IR, 1H NMR, and 13C NMR chromatographic data of the compounds with literature.
Abstract: The objective of this study is to extract, screen, isolate, and characterize the chemical constituents of Tephrosia vogelii and Commiphora schimperi. In the course of this study the stem bark of T. vogelii and resin of C. schimperi were collected from Areka Agricultural Research institute, Wolaita Zone and Konso, Gamo Gofa Zone, respectively. Phyto...
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Proximate and Amino Acid Analyses of the Rhizome of Nymphaea lotus (Water Lily)
Amagbor Stella Chinelo,
Umar Kabiru Jega
Issue:
Volume 7, Issue 3, September 2019
Pages:
54-57
Received:
16 August 2019
Accepted:
16 September 2019
Published:
26 September 2019
Abstract: The proximate composition and the amino acid profile analyses of the rhizome of Nymphaea lotus (water lily) were carried out based on standard methods reported by the association of official Analytical Chemists (AOAC). The results of the proximate analysis showed that Nymphaea lotus rhizome had moisture content of 48.83±3.22; crude protein 4.23±0.06; crude fibre 5.00±1.50; ash content 4.67±0.17; high available carbohydrate 35.44 ± 0.01 and energy value 742.10 kJ/100 g. The crude lipid content was low 1.83±0.60. The study detected seventeen different amino acids. The amino acid content in g/100 g protein content was: lysine = 3.11, histidine= 1.82, arginine= 4.25, aspartic acid = 7.60, threonine= 2.19, serine= 3.02, glutamic acid= 9.68, proline= 2.34, glycine= 3.06, alanine= 3.40, cycteine= 0.73, valine= 3.37, methionine= 1.09, isoleucine= 2.35, leucine= 8.24, tyrosine= 2.25 and phenylalnine= 3.72. The studied revealed that glutamic acid, aromatic acids, leucine and aspartic acid were the predominant amino acids. All essential amino acids were found to be higher than WHO/FAO/UNU requirement pattern for adults while leucine was found to be higher than the requirement pattern for preschool children. Lysine however was found to be the most limiting amino acid for preschool children. The presence of these compounds of nutritive value, as well as high energy value suggests that Nymphaea lotus rhizome could serve as a food supplement for livestock and humans.
Abstract: The proximate composition and the amino acid profile analyses of the rhizome of Nymphaea lotus (water lily) were carried out based on standard methods reported by the association of official Analytical Chemists (AOAC). The results of the proximate analysis showed that Nymphaea lotus rhizome had moisture content of 48.83±3.22; crude protein 4.23±0.0...
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Adsorption, Kinetic and Thermodynamic Studies for Mercury Extraction from Water Samples Using Mesoporous Silica
Issue:
Volume 7, Issue 3, September 2019
Pages:
58-64
Received:
15 August 2019
Accepted:
9 September 2019
Published:
29 September 2019
Abstract: Mercury is recognized internationally as an important pollutant since mercury and its compounds are persistent, bioaccumulative and toxic, and pose human and ecosystem risks. A critical aspect of mercury cycling is its bioaccumulation, mainly as methylmercury, along the contaminated water with mercury resulting in high risk of human. Adsorption of mercury from water samples on mesoporous silica, mercaptopropyl functionalysed-SBA-15 (MP-SBA-15) and diethylenetriamine functionalysed-SBA-15 (DETA-SBA-15) has been studied. SBA-15 was prepared by using Pluronic P123, PEO20PPO70PEO20 and tetraethylorthosilicate. Surface modification of SBA-15 was carried out by MP-TMS or DETA-TMS to produce MP-SBA-15 or DETA-SBA-15, respectively. SBA-15 and functionalised SBA-15 materials were characterised for BET surface area, pore size and pore volume. The adsorption kinetics and adsorption isotherms of functionalised SBA-15 for mercury were investigated. Results revealed that the adsorption kinetics were fitted by a pseudo-second-order reaction model and the adsorption thermodynamic parameters ΔH°, ΔS° and ΔE° were 42.08 kJ/mol, 210.3 J/mol.K and 7.20 kJ/mol, respectively for DETA-SBA-15; 101.85 kJ/mol, 397.7 J/mol.K and 23.28 kJ/mol, respectively for MP-SBA-15. Langmuir and Freundlich isotherm models were also applied to analyse the experimental data and to predict the relevant isotherm parameters. The best interpretation for the experimental data was given by the Langmuir isotherm equation. The results indicate that the structure of the materials affects the adsorption behavior. These materials show a potential for the application as effective and selective adsorbents for Hg(II) removal from water.
Abstract: Mercury is recognized internationally as an important pollutant since mercury and its compounds are persistent, bioaccumulative and toxic, and pose human and ecosystem risks. A critical aspect of mercury cycling is its bioaccumulation, mainly as methylmercury, along the contaminated water with mercury resulting in high risk of human. Adsorption of ...
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A Theoretical Study on the Stability, Reactivity and Protonic Affinity of 2-Phenylbenzothiazole Derivatives
Bede Affoue Lucie,
Kone Soleymane,
N’Guessan Boka Robert,
Yapo Kicho Denis,
Ziao Nahosse
Issue:
Volume 7, Issue 3, September 2019
Pages:
65-72
Received:
28 May 2019
Accepted:
20 September 2019
Published:
29 September 2019
Abstract: The 2-phenylbenzothiazole derivatives have antitumor activities. Work has shown that these derivatives have mesomeric forms. The electrophilic centers of these mesomers form adducts with the nucleophilic centers of deoxyribonucleic acid (DNA). These adducts destroy the tumor cells and prevent the proliferation of these. In this sense, the knowledge of electrophilic sites, nucleophiles and the capacity to protonate these derivatives is therefore useful if we want to know their future in the biological environment. Using DFT/B3LYP method associated with the bases 6-31G (d, p) and 6-31+G (d, p), this work aims at determining the preferential protonation site, the electrophilic and nucleophilic centers of six 2-phenylbenzothiazole. This study also analyzes the stability of these derivatives. Calculations are carried out in gas and aqueous phases. Results show that fluorinated derivatives are the most stable. 2-(4-aminophenyl) benzothiazoles are the most reactive. The atoms carbon C4, C5 and C6 of benzothiazole ring are the most electrophilic. Interactions of these derivatives with nucleophilic centers of deoxyribonucleic acid (DNA) will probably be at these atoms. Nitrogen sp2 (N1) of benzothiazole ring remains the most nucleophilic center and the preferential site of protonation in all the molecules studied. These results highlight the influence of the substituents on the basicity of the nitrogen sp2 (N1) and reactivity of the 2-phenylbenzothiazole derivatives studied.
Abstract: The 2-phenylbenzothiazole derivatives have antitumor activities. Work has shown that these derivatives have mesomeric forms. The electrophilic centers of these mesomers form adducts with the nucleophilic centers of deoxyribonucleic acid (DNA). These adducts destroy the tumor cells and prevent the proliferation of these. In this sense, the knowledge...
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Surface Engineering Effect on Optimizing Hydrogenation Timing of Green Hydrogenated Chitosan-Mediated CuO (H-Cht-CuO) for Cashew-kernel-oil Hydrogenation
Joshua Lelesi Konne,
Hamilton Amachree Akens,
Arinze Amauche Uwaezuoke,
Achu Golden Chiamaka
Issue:
Volume 7, Issue 3, September 2019
Pages:
73-79
Received:
22 August 2019
Accepted:
20 September 2019
Published:
29 September 2019
Abstract: The effect of polycrystallite surface engineering on the time required to fully hydrogenate green chitosan-mediated CuO to form hydrogenated chitosan-mediated CuO (H-Cht-CuO) as well as the catalytic properties of both CuO and H-Cht-CuO have been investigated. The prepared chitosan mediated CuO was obtained from the reaction of copper (II) sulphatepentahydrate with green alkali (aqueous extract of ripe plantain peel ash) via sol-gel technique (chitosan-gel mediated) and heated at 550°C for 6 h. The resultant sample was divided into two portions. The first was used as the control experiment (0 min) while the second was hydrogenated at varying times of 2 to 8 mins to form the H-Cht-CuO samples. A second CuO (control) without chitosan was also synthesized for structural and surface morphological comparisons with the chitosan-mediated using the XRD and SEM techniques, respectively. The XRD reflections showed differences in peak intensities with the chitosan-mediated having broader peaks while its SEM pores were 8.5 times larger than those of CuO (non chitosan-mediated). UV-Vis analysis of the samples showed that the 2 mins H-Cht-CuO sample had the maximum absorptivity while CuO (control-chitosan mediated) had the least. Both samples were used as catalysts in the hydrogenation of Cashew kernel oil. The GC-MS results showed that the Oleic acid component was reduced from 84.36% to 0.06% and 0%, Linoleic acid from 8.68% to 3.63% and 0% with increase in Stearic acid (saturated C18) from 4.88% to 34.97% and 84.76% by the CuO and H-Cht-CuO, respectively.
Abstract: The effect of polycrystallite surface engineering on the time required to fully hydrogenate green chitosan-mediated CuO to form hydrogenated chitosan-mediated CuO (H-Cht-CuO) as well as the catalytic properties of both CuO and H-Cht-CuO have been investigated. The prepared chitosan mediated CuO was obtained from the reaction of copper (II) sulphate...
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