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Item Near-infrared spectroscopy and chemometrics for rapid profiling of plant secondary metabolites.(De Gruyter, 2013-09-30) Mokgalaka, Ntebogeng S.; Lepule, Sello P.; Regnier, Thierry; Combrinck, SandraIn this study, near-infrared (NIR) spectroscopy, in combination with chemometrics, was used as a rapid tool for determining if exposure to contamination from mine tailings influences the matrices of the specimens, compared to those from natural populations. Principal component analysis (PCA) plots were made from the chemometric models obtained to establish if season of harvest, geographical origin, and level of soil contamination play a determining role in the chemical profiles of the individual specimens harvested from mine sites or natural populations. The random distribution on PCA score plots corroborated the intraspecies variation of Lippia scaberrima previously observed by gas chromatography flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS) essential oil profiles. Clustering according to the season and origin of the individual plants confirmed that the geographic location and the season of harvest influence the chemical profiles of L. scaberrima. The NIR data could not be correlated with the level of soil contamination to which the specimens were exposed. The PCA scores and loadings plots obtained from NIR data of Searsia pendulina suggest that the species is tolerant to pollution from mine tailings. Although separation was obtained in a three-component PCA model between specimens sampled during different seasons, some clustering was observed by specimens from the same geographical origin.Item The crystal structure of fac-tricarbonyl(6-bromo- 2,2-bipyridine-κ2N,N)-(nitrato-κO)rhenium(I), C13H7BrN3O6Re.(De Gruyter, 2023-04-14) Mkhatshwa, Marcus; Malan, Frederick P.; Makgopa, Katlego; Manicum, Amanda-Lee E.C13H7BrN3O6Re, monoclinic, P21/n (no. 14), a = 7.2645(1) Å, b = 10.0607(1) Å, c = 20.7717(2)Å, β = 97.1800(10) °, V = 1506.22(3) Å3, Z = 4, Rgt (F) = 0.0359, wRref (F2) = 0.0810, T = 150K.Item One-step hdrothermal synthesis of nitrogen-doped reduced graphene oxide/hausmannite manganese oxide for symmetric and asymmetric pseudocapacitors.(American Chemical Society, 2021-11-15) Makgopa, Katlego; Ratsoma, Mpho S.; Raju, Kumar; Mabena, Letlhogonolo F.; Modibane, Kwena D.In this paper, the pseudocapacitive performance of nitrogen-doped and undoped reduced graphene oxide/tetragonal hausmannite nanohybrids (N-rGO/Mn3O4 and rGO/Mn3O4) synthesized using a one-pot hydrothermal method is reported. The nanohybrid electrode materials displayed exceptional electrochemical performance relative to their respective individual precursors (i.e., reduced graphene oxide (rGO), nitrogen-doped reduced graphene oxide (N-rGO), and tetragonal hausmannite (Mn3O4)) for symmetric pseudocapacitors. Among the two nanohybrids, N-rGO/Mn3O4 displayed greater performance with a high specific capacitance of 345 F g−1 at a current density of 0.1 A g−1, excellent specific energy of 12.0 Wh kg−1 (0.1 A g−1), and a high power density of 22.5 kW kg−1 (10.0 A g−1), while rGO/Mn3O4 demonstrated a high specific capacitance of 264 F g−1 (0.1 A g−1) with specific energy and power densities of 9.2 Wh kg−1 (0.1 A g−1) and 23.6 kW kg−1 (10.0 A g−1), respectively. Furthermore, the NrGO/ Mn3O4 nanohybrid exhibited an impressive pseudocapacitive performance when fabricated in an asymmetric configuration, having a stable potential window of 2.0 V in 1.0 M Na2SO4 electrolyte. The nanohybrid showed excellent specific energy and power densities of 34.6 Wh kg−1 (0.1 A g−1) and 14.01 kW kg−1 (10.0 A g−1), respectively. These promising results provide a good substance for developing novel carbon-based metal oxide electrode materials in pseudocapacitor applications.Item Fabrication, characterization, and photovoltaic performance of titanium dioxide/metal-organic framework composite.(Elsevier B.V., 2022-08-30) Ramaripa, Phuti S; Modibane, Kwena D.; Makgopa, Katlego; Seerane, Ostar A; Maubane-Nkadimeng, Manoko S.; Makhado, Edwin; Hato, Mpitloane J.; Ramoroka, Morongwa E.; Molapo, Kerileng M.; Iwuoha, EmmanuelTitanium dioxide/metal organic framework (TiO 2 /MOF) nanocomposite was prepared using the sol-gel method and was employed as photoanode material for photovoltaic applications. X-ray diffraction patterns (XRD), Fourier transform infrared (FTIR), thermal gravimetric analysis/ differential thermal analysis (TGA/DTA), and Raman analyses showed the presence of MOF clusters in the TiO 2 sol-gel network. The scanning electron microscopic (SEM) images revealed the smooth irregular shape of TiO 2, the octahedral shape of MOF, and the continuous arrangement of pore-solid network structure for nanocomposite. The resultant nanocomposite material showed a Brunauer, Emmett and Teller (BET) surface area of 111.10 m 2 g − 1 as compared to the surface area of TiO 2 (262.90 m 2 g −1 ) and MOF (464.76 m 2 g -1 ). It was seen that an increase in average pore size of 3.40 nm for nanocomposite analogous with the pore size of TiO 2 (2.66 nm) and MOF (2.56 nm). Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronoamperometry (CA) were used to determine the energy level and suggest a fast electron transfer as well as high ionic conductivity. The overall power conversion efficiency of 0.722% along with a photocurrent density of 0.46 mA cm − 2 was achieved for composite. The approach proposed in this work is facile and can be used for the large-scale fabrication of efficient flexible photoanode electrodes for photovoltaic applications.Item Influence of phthalocyanine nanowire dye on the performance of titanium dioxide-metal organic framework nanocomposite for dye-sensitized solar cells.(Elsevier B.V., 2023-03-29) Ramaripa, Phuti S.; Modibane, Kwena D.; Makgopa, Katlego; Seerane, Ostar A.; Maubane-Nkadimeng, Manoko S.; Makhado , Edwin; Pandey, SadanandIn clean energy, dye-sensitized solar cells (DSSCs) have become a key tool for the photovoltaic effect. Copper phthalocyanine nanowire (CuPcNW) dyes can be used in DSSCs to generate low-cost devices, light-harvesting, fast electron transfer materials, and prevent recombination processes, as well as improve conductivity. This study investigates the effect of CuPcNW dye on TiO2, MOF, and TiO2-MOF in photovoltaic performance. Electrochemical characterizations such as cyclic voltammetry and electrochemical impedance spectroscopy (EIS) have also revealed the half-wave peak potentials of the ternary nanocomposite with values of 0.44 and 0.35 V for the oxidation and reduction reversible reactions. The EIS behavior revealed the improved conductivity of the nanocomposite with a value of 244 μS/cm. It was seen that the TiO2-MOF/CuPcNW nanocomposite achieved a maximum power conversion efficiency of 6.467 % owing to the presence of CuPcNW, which improved the photocurrent density, faster electron transport, and reduced charge recombination in the nanocomposite.Item African legumes: A vital but under-utilized resource.(Oxford University Press, 2009-11-25) Sprent, Janet I.; Odee, David W.; Dakora, Felix D.Although nodulated legumes have been used by indigenous peoples in Africa for centuries, their full potential has never been realized. With modern technology there is scope for rapid improvement of both plant and microbial germplasm. This review gives examples of some recent developments in the form of case studies; these range from multipurpose human food crops, such as cowpea (Vigna unguiculata (L.) Walp.), through to beverages (teas) that are also income-generating such as rooibos (Aspalathus linearis (Burm. f.) R. Dahlgren, honeybush (Cyclopia Vent. spp.), and the widely used food additive gum arabic (Acacia senegal (L.) Willd.). These and other potential crops are well adapted to the many different soil and climatic conditions of Africa, in particular, drought and low nutrients. All can nodulate and fix nitrogen, with varying degrees of effectiveness and using a range of bacterial symbionts. The further development of these and other species is essential, not only for African use, but also to retain the agricultural diversity that is essential for a changing world that is being increasingly dominated by a few crops such as soybean.Item Field assessment of symbiotic N2 fixation in wild and cultivated cyclopia species in the South African fynbos by 15N natural abundance.(Oxford University Press, 2008-08-24) Spriggs, Amy C.; Dakora, Felix D.Nitrogen (N) derived from symbiotic fixation of atmospheric N2 in wild and cultivated populations of Cyclopia, a woody endemic genus used to make honeybush tea in the Western Cape of South Africa, was quantified by the 15N natural abundance method. Because Cyclopia species are naturally mycorrhizal, non-N2-fixing arbuscular mycorrhizal shrubs of similar phenology to Cyclopia were chosen as reference plants to provide the d15Nvalue of soil-derived N. Isotopic analysis showed that wild populations of Cyclopia were highly dependent on N2 fixation for their nutrition, ranging from 70 ± 4%to 100 ± 7% (mean ± SE) at all sites, except for one. Further evidence of the high dependency of wild Cyclopia populations on symbiotic N was provided by their significantly higher foliar N concentrations compared with the non-legume reference plants. However, cultivated Cyclopia exhibited variable amounts of N2 fixation, with Cyclopia genistoides (L.) R. Br., for example, showing low amounts of N2 fixation at Sites P2 and P3 (0 ± 51% and 8 ± 46%, respectively) as a result of low D values (D is defined as the difference between the mean d15N value of the reference plants and the B value of the test Cyclopia species, where B is the d15N of an inoculated test legume grown in an N-free growth medium), whereas at Sites P1, P2, P5 and P6, up to 89 ± 2%, 94 ± 13%, 85 ± 13% and 100 ± 18%, respectively, plant N was derived from atmospheric fixation. The high symbiotic N nutrition observed for wild populations of Cyclopia suggests that these populations are major contributors to the N economy of the nutrient poor soils of the South African fynbos. These data indicate that by breeding for high N2 fixation rates in Cyclopia cultivars and selecting more efficient rhizobial strains, this legume has the potential to achieve higher N2 fixation rates under cultivation. The low variability in Cyclopia d15N values within sites, however, suggests that genetic variability is not a major factor influencing N2 fixation rates in cultivated Cyclopia, and that more benefit may be gained from soil amelioration and the selection of improved rhizobial strains.Item Plant-associated symbiotic burkholderia species lack hallmark strategies required in mammalian pathogenesis.(Public Library of Science, 2014-01-08) Angus, Annette A.; Agapakis, Christina M.; Fong, Stephanie; Yerrapragada, Shailaja; De Los Santos, Paulina Estradade ; Yang, Paul; Song, Nannie; Kano, Stephanie; Caballero-Mellado, Jesus; De Faria, Sergio M.; Dakora, Felix D.; Weinstock, George; Hirsch, Ann M.Burkholderia is a diverse and dynamic genus, containing pathogenic species as well as species that form complex interactions with plants. Pathogenic strains, such as B. pseudomallei and B. mallei, can cause serious disease in mammals, while other Burkholderia strains are opportunistic pathogens, infecting humans or animals with a compromised immune system. Although some of the opportunistic Burkholderia pathogens are known to promote plant growth and even fix nitrogen, the risk of infection to infants, the elderly, and people who are immunocompromised has not only resulted in a restriction on their use, but has also limited the application of non-pathogenic, symbiotic species, several of which nodulate legume roots or have positive effects on plant growth. However, recent phylogenetic analyses have demonstrated that Burkholderia species separate into distinct lineages, suggesting the possibility for safe use of certain symbiotic species in agricultural contexts. A number of environmental strains that promote plant growth or degrade xenobiotics are also included in the symbiotic lineage. Many of these species have the potential to enhance agriculture in areas where fertilizers are not readily available and may serve in the future as inocula for crops growing in soils impacted by climate change. Here we address the pathogenic potential of several of the symbiotic Burkholderia strains using bioinformatics and functional tests. A series of infection experiments using Caenorhabditis elegans and HeLa cells, as well as genomic characterization of pathogenic loci, show that the risk of opportunistic infection by symbiotic strains such as B. tuberum is extremely low.Item DnaK protein interaction of phage marked Bradyrhizobium of soybean.(BMC, 2013-12-19) Jaiswal, Sanjay Kumar; Vaishampayan, Akhouri; Singh, Vinay Kumar; Vaishampayan, Akhouri; Dhar, Banshi; Dakora, Felix DapareThe ability to rapidly adapt to changes in their environment is essential for the survival of microorganisms. DnaK is the prokaryotic analogue of eukaryotic Hsp70. These proteins protect the cell against heat injury or other forms of stress. In the present research, 78 rhizobial isolates were collected from different geographical regions of India and tested for their sensitivity. Forty-two out of 78 were shown to be susceptible to eight isolated phages. Only six Rhizobium strains out of 42 (MPSR033, MPSR041, MPSR052, MPSR084, MPSR220 and UPSR095) showed susceptibility to a single phage strain separately. All of these six rhizobial strains were slow growing and had the capability of Ex-planta nitrogenase activities. The PCR amplification of the dnaK region of the selected strain showed a single band~ 600 bp in length. The restriction endonuclease analysis of dnaK regions produced six restriction patterns. Sequence BLASTn analysis of DnaK showed linkage with Actinobacterium sp. and Bradyrhizobium sp. Multiple sequence alignment of all six Rhizobium dnaK regions exhibited a 99 % similarity betweenMPSR041 andMPSR220 and formed a close cluster with UPSR095 and MPSR033. The Prosite database showed that the functional domain of the DnaK protein presented three signatures, PS00297 IDLGTTNS (HSP70_1), PS00329 VYDLGGGTFDISIL (HSP70_2) and PS01036 VVLVGGMSRMPKVQE (HSP70_3), which belong to the HSP70 protein family. An in-silico interaction study revealed that DnaK protein is involved in interactions with blr, gap, grpE, pgk, hrcA and recA heat-shock proteins.Item Quantification of trace elements in raw cow’s milk by inductively coupled plasma mass spectrometry (ICP-MS).(Elsevier Ltd., 2008-03-16) Ataro, A.; McCrindle, R.I.; Botha, B.M.; McCrindle, C.M.E.; Ndibewu, P.P.The levels of trace elements are an important component of safety and quality of milk. While certain elements such as chromium are essential at low levels, an excess can result in deleterious effects on human health. International quality control standards for milk are published by the Codex Alimentarious Commission and levels of heavy metals in milk intended for human consumption are routinely monitored. This paper describes a new method for demonstrating the levels of V, Cr, Mn, Sr, Cd and Pb in raw cow’s milk, using an ICP-MS. Samples (n = 24) of raw cow’s milk were collected from dairy farms close to mines in Gauteng and Northwest Provinces of South Africa. In order to destroy organic matrix, each freeze-dried milk sample was mineralised by using a microwave assisted digestion procedure. Concentrations of trace elements in digested milk samples were measured by ICP-MS. A whole milk powder reference material (NIST SRM 8435) was used to evaluate the accuracy of the proposed method. It was found that the levels of V, Cr, Mn, Sr, Cd and Pb obtained using the new method showed concordance with certified values.Item Science and technology backyard model: Implications for sustainable agriculture in Africa.(Higher Education Press, 2020-08-25) Jiao, Xiaoqiang; Feyisa, Derara Sori; Kanomanyanga, Jasper; Muttendango, Ngula David; Mudare, Shingirai; Ndiaye, Amadou; Kabeto, Bilisuma; Dakora, Felix DapareSustainable food production to feed the growing population in Africa remains a major challenge. Africa has 64% of the global arable land but produces less than 10% of its food locally due to its inherently low soil nutrient concentrations. Poor soil fertility and a lack of fertilizer use are the major constraints to increasing crop yields in Africa. On average only about 8.8 kg NPK fertilizer is applied per hectare by African smallholder farmers. There is therefore considerable potential for increasing food production through sustainable intensification of the cropping systems. The low crop yields in Africa are also partly due to limited farmer access to modern agronomic techniques, including improved crop varieties, a lack of financial resources, and the absence of mechanisms for dissemination of information to smallholders. This study analyzed the Science and Technology Backyards (STBs) model and investigated its use for them transformation of agriculture in Africa. Some key lessons for sustainable crop intensification in Africa can be found from analysis of the STB model which is well established in China. These include (1) scientist-farmer engagement to develop adaptive and innovative technology for sustainable crop production, (2) dissemination of technology by empowering smallholders, especially leading farmers, and (3) the development of an open platform for multiple resource involvement rather than relying on a single mechanism. This review evaluates the benefits of the STB model used in China for adoption to increase agricultural productivity in Africa, with a perspective on sustainable crop intensification on the continent.Item Antimicrobial and anti-biofilm activities of bio-inspired nanomaterials for wound healing applications(Elsevier, 2023-09) Arshad, Rabia; Razlansari, Mahtab; Hosseinikhah, Seyedeh Maryam; Pandey, Aprajita Tiwari; Ajalli, Narges; Manicum, Amanda-Lee Ezra; Thorat, Nanasaheb; Rahdar, Abbas; Zhu, Yangzhi; Tabish, Tanveer AChronic wounds are ubiquitously inhabited by bacteria, and they remain a challenge as they cause significant discomfort and because their treatment consumes huge clinical resources. To reduce the burden that chronic wounds place upon both patients and health services, a wide variety of approaches have been devised and investigated. Bioinspired nanomaterials have shown great success in wound healing when compared to existing approaches, showing better ability to mimic natural extracellular matrix (ECM) components and thus to promote cell adhesion, proliferation, and differentiation. Wound dressings that are based on bioinspired nanomaterials can be engineered to promote anti-inflammatory mechanisms and to inhibit the formation of microbial biofilms. We consider the extensive potential of bioinspired nanomaterials in wound healing, revealing a scope beyond that covered previously.Item In vitro toxicity and internalization of gold nanoparticles (AuNPs) in human epithelial colorectal adenocarcinoma (Caco-2) cells and the human skin keratinocyte (HaCaT) cells.(Elsevier, 2022-09-29) Magogotya, M.; Vetten, M.; Roux-Van der Merwe, M.P.; Badenhorst, J.; Gulumian, M.Ingestion and transdermal delivery are two common routes of nanoparticle (NP) exposure. In this study, the intracellular uptake, cytotoxicity and genotoxicity of 14 nm and 20 nm citrate-stabilized gold nanoparticles (AuNPs), 14 nm polyethylene glycol (PEG)-liganded carboxyl AuNPs, 14 nm PEG-liganded hydroxyl AuNPs and 14 nm PEG-liganded amine AuNPs were assessed on human epithelial colorectal adenocarcinoma (Caco-2) cells and the human skin keratinocyte (HaCaT) cells. The uptake of AuNPs in the cells was confirmed through darkfield microscopy and hyperspectral imaging followed by spectral angle mapping (SAM). A high level of citrate AuNPs was found in both cell lines whilst uptake of PEGylated AuNPs was low, irrespective of their functional groups. Cytotoxicity assessed by cell impedance was only observed for the 14 nm citrate-stabilized AuNPs. Enhanced cell proliferation was also observed in 14 nm PEG-liganded hydroxyl and 14 nm PEGliganded amine AuNP-treated Caco-2 and HaCaT cells. For the assessment of genotoxicity, the in vitro micronucleus assay was used. Dose-dependent genotoxicity was observed in both Caco-2 and HaCaT cells, with all the AuNPs inducing genotoxicity. In conclusion, the entry of NPs into the cells as well as toxicity was dependent on their physicochemical properties such as surface coating and different chemical functional groups.Item Antifungal properties of nanosilver clay composites against fungal pathogens of agaricus bisporus.(Wiley, 2023-08) Ramakutoane, Tebogo Levy; Roux-van der Merwe, Magaretha Petronella; Badenhorst, Jacqueline; Pillai, Sreejarani Kesavan; Ray, Suprakas SinhaThis study aimed to determine the possible control of selected pathogenic and competitive fungi of A. bisporus by threenanosilver clay composites and establish the effective concentrations of the composites for inhibiting pathogens. Nanosilver(AgNPs) clay (zeolite, montmorillonite, and palygorskite) composites were synthesized by a microwave-assisted surfacefunctionalization technique, and various techniques characterized the products. Zeolite and montmorillonite composites showed uniformly distributed spherical AgNPs with an average size of 3.33 nm and 2.85 nm, respectively, whereas palygorskite presented agglomerated and unevenly distributed AgNPs. The influence of the various composites on 9 fungi, including strains of T. aggressivum f. aggressivum, L. fungicola, C. dendroides, and Mycogone sp., was determined in vitro at different concentrations. At 10 mg/mL, AgNP-zeolite and AgNP-montmorillonite inhibited 8 out of 9 pathogens, while AgNP-palygorskite only inhibited 1 pathogen. The nanosilver clay composites tested against A. bisporus revealed no adverse effects on mycelial growth at any concentrations tested. This study confirms that AgNP-zeolite and AgNP-montmorillonite composites have effective antifungal properties and can be used as alternative fungicides against mushroom pathogens without affecting A. bisporus growth. However, further investigation is required to unravel the mechanism of selective antifungal activity observed in this study.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-LeeSpecies 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 PurinCoinoculation 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.Item Steric and electronic influence of Re(I) tricarbonyl complexes with various coordinated β-diketones(Elsevier, 2022-05-09) Manicum, Amanda-Lee Eza; Schutte-Smith, Marietjie; Malan, Frederick P.; Visser, Hendrik GideonRe(I) tricarbonyl complexes, with coordinated β-diketones, are the center of attention as they form part of a library of promising cancer therapeutic and diagnostic agents. In this study, we present three new Re(I) crystal structures. {fac [Re(Benzac)(CO)3(PCy3)] (4), fac-[Re(Tfaa)(CO)3(PCy3)] (5), and fac-[Re(Hfaa)(CO)3(PCy3)] (6); benzoylacetone = Benzac; trifluoroacetylacetone = Tfaa and hexafluoroacetylacetone = Hfaa; PCy3 = tricyclohexylphosphine}. The three reported complexes were synthesized with ease and good yield, involving the "2 + 1" mixed ligand approach. The complexes were characterized using analytical tools: IR, NMR, UV/Vis, single-crystal X-ray diffraction. The Tolman cone angles (θ) were calculated as 141.93°, 148.77°, and 149°; and compared to the Equivalent cone angles obtained from DFT calculations. These were 131.25°, 134.34°, and 134.28° for (4), (5), and (6), respectively. The DFT analysis observed that the Re-P bond distances decrease as the number of electron-withdrawing groups (CF3) on the β-diketonato ligands increase. In general, the theoretical and experimental Re-P and Re-OOO bond distances compared well among the complexes, with the most significant deviation occurring for 4 (relative differences of 0.055 A˚ (Re-P) and 0.015 A˚ (average Re-O)). Hirshfeld surface analysis was used to obtain the fingerprint plots, and the Hirshfeld surfaces were mapped with dnorm for 4, 5, and 6.