TUT DIGITAL OPEN REPOSITORY

Recent Submissions

  • Item
    Crystal structure of fac-(acetylacetonato-κ2O,O′) tricarbonyl(tri-m-tolyl phosphane-κP)rhenium(I), C29H28O5PRe
    (De Gruyter, 2017-10-23) Manicum, Amanda-Lee; Alexander, Orbett; Schutte-Smith, Marietjie; Visser, Hendrik G.
    C29H28O5PRe, monoclinic, P21/n (no. 14), a = 10.548(5) Å,b = 22.996(5) Å, c = 11.022(5) Å, β = 98.011(5)°, V =2647.4(18) Å3, Z = 4, Rgt(F) = 0.0306, wRref(F2) = 0.0911,T = 100 K.
  • Item
    Review of the traditional uses, phytochemistry, and pharmacological activities of rhoicissus species (Vitaceae)
    (MDPI, 2021-03-25) Dube, Nondumiso P; Siwe-Noundou, Xavier; Krause, Rui W. M.; Kemboi, Douglas; Tembu, Vuyelwa Jacqueline; Manicum, Amanda-Lee
    Species within the genus Rhoicissus (Vitaceae) are commonly used in South African traditional medicine. The current review discusses the occurrence, distribution, traditional uses, phytochemistry, and pharmacological properties of Rhoicissus species covering the period 1981–2020. The data reported were systematically collected, read, and analysed from scientific electronic databases including Scopus, Scifinder, Pubmed, and Google Scholar. Reported evidence indicates that species in this genus are used for the treatment of gastrointestinal complaints, sexually transmitted infections (STIs), and infertility, as well as to tone the uterus during pregnancy and to facilitate delivery. Pharmacological studies have further shown that members of the Rhoicissus genus display antidiabetic, uterotonic, ascaricidal, hepatoprotective, antioxidant, antimicrobial, anticancer, and anti-inflammatory properties. They are linked to the presence of bioactive compounds isolated from the genus. Hence, Rhoicissus species can potentially be an alternative therapeutic strategy to treat diseases and develop safer and more potent drugs to combat diseases. Plant species of this genus have valuable medicinal benefits due to their significant pharmacological potential. However, scientific investigation and information of the therapeutic potential of Rhoicissus remain limited as most of the species in the genus have not been fully exploited. Therefore, there is a need for furtherinvestigations to exploit the therapeutic potential of the genus Rhoicissus. Future studies should evaluate the phytochemical, pharmacological, and toxicological activities, as well as the mode of action, of Rhoicissus crude extracts and secondary compounds isolated from the species.
  • Item
    Transition metal-decorated B12N12−X (X = Au, Cu, Ni, Os, Pt, and Zn) nanoclusters as biosensors for carboplatin.
    (ACS Publications, 2023-01-09) Benjamin, Innocent; Louis, Hitler; Okon, Gideon A.; Qader, Suhailah W.; Afahanam, Lucy E.; Fidelis, Chidera F.; Eno, Ededet A.; Ejiofor, Emmanuel E.; Manicum, Amanda-Lee E.
    Theoretical studies on the adsorption, sensibility, and reactivity of a boron nitride nanocage decorated with Au, Cu, Ni, Os, Pt, and Zn metals as a biosensor material were carried out for the adsorption of carboplatin by applying the density functional theory computation at the B3LYP-GD3BJ/def2svp level of theory. All the optimized structures, as well as the calculations as regards the studied objective including electronic properties, geometry optimization parameters, adsorption energy studies, natural bond orbital analysis, topology studies, sensor mechanistic parameters, and thermodynamic properties (ΔG and ΔH), were investigated herein. As a result, the noticeable change in the energy gap of the studied surfaces when interacting with carboplatin accounted for the surfaces’ reactivity, stability, conductivity, work function, and overall adsorption ability, implying that the studied decorated surfaces are good sensor materials for sensing carboplatin. Furthermore, the negative adsorption energies obtained for interacting surfaces decorated with Cu, Ni, Os, and Zn suggest that the surface has a superior ability to sense carboplatin as chemisorption was seen. Substantially, the geometric short adsorption bond length after adsorption, thermodynamically spontaneous reactions, and acceptable sensor mechanism results demonstrate that the investigated surfaces have strong sensing characteristics for sensing carboplatin.
  • Item
    Heteroatom (B, N, P, and S)-doped Cyclodextrin as a Hydroxyurea (HU) drug Nanocarrier: A computational approach
    (ACS Publications, 2022-12-20) Afahanam, Lucy E.; Louis, Hitler; Benjamin, Innocent; Gber, Terkumbur E.; Ikot, Immaculata J.; Manicum, Amanda-Lee E.
    Theoretical examination of hydroxyurea adsorption capabilities toward the cyclodextrin surface for proper drug delivery systems was carried out utilizing DFT simulations. The study aims to assess the efficacy of doped cyclodextrin (doped with boron, nitrogen, phosphorus, and sulfur atoms) in increasing its stability and efficiency in intermolecular interactions, hence facilitating optimal drug delivery. The adsorption energies were found to follow a decreasing order of B@ACD-HU>N@ACD-HU>P@ ACD-HU>S@ACD-HU with energies of −0.046, −0.0326, −0.015, and 0.944 kcal/mol, respectively. The S@ACD-HU complex, unlike previous systems, had a physical adsorption energy. The N@ACD-HU and B@ACD-HU complexes had the shortest bond lengths of 1.42 Å (N122-C15) and 1.54 Å (B126- C15), respectively. The HOMO and LUMO values were also high in identical systems, −6.367 and −2.918 eV (B@ACD-HU) and −6.278 and −1.736 eV (N@ACD-HU), respectively, confirming no chemical interaction. The N@ACD-HU has the largest energy gap of 4.54 eV. For the QTAIM analysis and plots, the maximum electron density and ellipticity index were detected in B@ACD HU, 0.600 au (H70-N129) and 0.8685 au (H70-N129), respectively, but N@ACD-HU exhibited a high Laplacian energy of 0.7524 a.u (H133-N122). The fragments’ TDOS, OPDOS, and PDOS exhibited a strong bond interaction of greater than 1, and they had different Fermi levels, with the highest value of −8.16 eV in the N@ACD-HU complex. Finally, the NCI analysis revealed that the complexes were noncovalent. According to the literature, the van der Waals form of interactions is used in the intermolecular forces of cyclodextrin cavities. The B@ACD-HU and N@ACD-HU systems were more greenish in color with no spatial interaction. These two systems have outperformed other complexes in intermolecular interactions, resulting in more efficient drug delivery. They had the highest negative adsorption energies, the shortest bond length, the highest HOMO/LUMO energies, the highest energy gap, the highest stabilization energy, the strongest bonding effect, the highest electron density, the highest ellipticity index, and a strong van der Waals interaction that binds the drug and the surface together.
  • Item
    Coinoculation impact on plant growth promotion: A review and meta‑analysis on coinoculation of rhizobia and plant growth‑promoting bacilli in grain legumes.
    (Springer, 2022-07-28) Kaschuk, Glaciela; Aule, André Carlos; Vieira, Crislaine Emidio; Dakora, Felix Dapore; Jaiswal, Sanjay K.; Da Cruz, Sonia Purin
    Coinoculation of symbiotic N2- fixing rhizobia and plant growth-promoting Bacillus on legume seeds can increase crop productivity. We collected highly resolved data on coinoculation of rhizobia and bacilli on 11 grain legume crops: chickpea, common bean, cowpea, faba bean, groundnut, lentil, mung bean, pea, pigeon pea, soybean, and urad bean to verify the magnitude of additive effects of coinoculation in relation to single inoculation of rhizobia on plant growth and yield of grain legumes. Coinoculation of rhizobia and bacilli on legume seeds and/or soil during sowing significantly increased nodulation, nitrogenase activity, plant N and P contents, and shoot and root biomass, as well as the grain yield of most grain legumes studied. There were however a few instances where coinoculation decreased plant growth parameters. Therefore, coinoculation of rhizobia and Bacillus has the potential to increase the growth and productivity of grain legumes and can be recommended as an environmental-friendly agricultural practice for increased crop yields.