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Erythroside: a new cerebroside and other compounds rrom Erythrina caffra Thunb. (Fabaceae) stem bark, with cytotoxicity and antioxidant evaluation
Tsakem, Bienvenu; Serem, June Cheptoo; Hlophe, Yvette Nkondo; Kengne, Michael H. Kamdem; Sandjo, Louis P.; Ndinteh, Derek T.; Teponno, Remy B.; Ambele, Melvin Anyasi; Noundou, Xavier Siwe (Wiley, 2026-04)
The chemical investigation of a CH2Cl2:MeOH (1:1) extract of the stem bark of Erythrina caffra resulted in the isolation and characterisation of the novel cerebroside, erythroside (1), alongside eight other known compounds (2‐9). The isolated compounds were characterized by FT‐IR, 1D and 2D NMR spectroscopy, and ESI‐MS analysis. Of the eight known compounds, 2, 3, 5, and 7 are isolated for the first time from the genus Erythrina. The crude extract, its fractions, and selected isolated compounds were evaluated for cytotoxicity against three normal cell lines, human keratinocytes (HaCaT), human melanocytes (NHEM‐Ad), and Human Embryonic Kidney 293 (HEK293), using the resazurin/Alamar blue and crystal violet assays. Antioxidant potential was also assessed through both the oxygen radical absorbance capacity (ORAC) and the Trolox equivalent antioxidant capacity (TEAC) assays. Most compounds showed no cytotoxic effects on these cell lines. The antioxidant assay revealed that compound 1 had a moderate antioxidant effect in the ABTS assay (0.50 µmol TE/mg) and good antioxidant capacity in the ORAC assay (0.87 µmol TE/mg). In contrast, almost all these compounds and extracts have shown moderate to good antioxidant effects in the ORAC assay. The results offer valuable insights into the chemical constituents of Erythrina caffra stem bark, their effects on HaCaT, NHEM‐Ad, and HEK 293 cells, as well as their antioxidant potential. Future research could focus on identifying additional bioactive compounds within the ethyl acetate fraction that may be responsible for the observed toxicity.
Petrogenesis of syenites at Phalaborwa, Kaapvaal Craton: (isotope) geochemical, modelling and age constraints
Bolhar, Robert; Maghdour-Mashhour, Reza; Milani, Lorenzo; Mondal, Suman; O'Sullivan, Gary J.; Klemd, Reiner; Chang, Qing (Elsevier, 2026-04)
Whole rock major and trace element data and apatite compositions (including Nd isotopes) for fifteen syenites from intrusions surrounding the Phalaborwa carbonatite-phoscorite Complex are presented to evaluate magmatic sources, processes, and also petrogenetic relationships across alkaline provinces in the Kaapvaal Craton. Thermodynamic modelling (alphaMELTS) of fractional crystallization assuming a gabbroic parental melt reproduces syenite compositions, involving early clinopyroxene and apatite removal, dominant K-feldspar crystallization with minor ilmenite and magnetite, and late biotite and quartz fractionation. Discrepancies between observed and modelled major element compositions (higher K₂O, Al₂O₃; lower CaO, Na₂O, P₂O₅) are explained by accumulation of K-feldspar (minor biotite and clinopyroxene) and dilution by apatite, plagioclase and Ti-oxides. Apatite displays zoning and high REE–Sr contents indicative of a magmatic origin. Minor and compositionally distinct apatite and unradiogenic εNd (2.06 Ga) (−1.4 to −12.0) imply assimilation of granitic/gneissic basement in some syenites. For most syenites, however, mixing models using suitable endmembers do not reproduce whole rock compositions. LA-SF-ICP-MS U-Pb ages of zircon, titanite, rutile and monazite range from 2.03 to 1.86 Ga. Titanite and rutile ages (1936 ± 24 Ma, 1860 ± 65 Ma, 2 SE) record post-emplacement hydrothermal alteration. Only one monazite age of 2032 ± 9 (2 SE) Ma likely dates magmatic emplacement, slightly post-dating emplacement of the 2060 Ma carbonatite-phoscorite complex, but coeval with mafic dyke intrusions. Imprecise zircon upper-intercept ages (2.5–1.9 Ga) and petrographic features in zircon, titanite and rutile are ascribed to hydrothermal alteration by fenitizing fluids or thermal overprinting related to dyke emplacement. We propose a model whereby alkaline melts at Phalaborwa were (partly) derived from metasomatically-enriched subcontinental lithospheric mantle (SCLM). Mantle (re)fertilization likely began during a 2.9–2.8 Ga subduction event and continued with a major ∼2.0 Ga hydrous metasomatic episode. A shared SCLM signature among several Kaapvaal alkaline complexes therefore registers (plume-induced?) melting of a subduction-metasomatized lithospheric mantle as an important crust formation process at 2 Ga.
Interfacial charge transfer in Z-scheme CeO2/AgFe2O3 heterojunction for the photocatalytic degradation of atrazine and electrochemical performance
Oluwole, Adewumi Olumayor; Molekwa, Karabo; Sarr, Samba; Yusuf, Tunde Lewis; Tichapondwa, Shepherd Masimba; Daramola, Michael Olawale; Iwarere, Samuel Ayodele (Elsevier, 2026-08)
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Alternative approaches and plant-based remedies for livestock health management among the Batswana of southern Africa : a review
Mpolokeng, Tswelelopele G.; Shikwambana, Ndzalama; Chakale, Mompati V.; Asong, John A.; McGaw, Lyndy Joy; Amoo, Stephen O.; Masondo, Nqobile A.; Aremu, Adeyemi O. (Wiley, 2026-04)
Due to limited access to, and the high cost of conventional veterinary services, Batswana communities often rely on ethnoveterinary practices for livestock health management. This review provides an in-depth analysis on the ethnoveterinary uses, biological properties and safety assessment of plants utilised in livestock husbandry. A systematic literature search was conducted using scientific databases, focusing on articles published from 1997 to 2024. After generating the inventory of plants with ethnoveterinary data, further search was conducted to assess the documented biological activities, safety, and phytochemicals for the recorded plants. A total of 116 plants were documented as remedies for managing nine livestock conditions. The most cited health conditions were retained placenta (81 citations), diarrhoea (65), and wounds (44). The most prominent plants were Senna italica (10 citations), Terminalia sericea (8 citations), and Ziziphus mucronata (8 citations). Approximately 52% of the 116 plants with ethnoveterinary records have empirical data on their biological effect, safety, and phytochemicals. Antimicrobial screening was the most common assay conducted (36%), which dominantly used microbial strains such as Staphylococcus spp., Pseudomonas aeruginosa, and Escherichia coli. We established the vital role of ethnoveterinary practices in Batswana livestock management and the potential of plants in sustainable veterinary care.
Preparation of activated carbons from ZIF-8 using cellulose acetate as an additional carbon source
Khethula, Nwabisa; Ndamyabera, Christophe Adrien; Langmi, Henrietta Wakuna (Wiley, 2026-03-05)
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