Browsing by Author "Makhaba, Masixole"

Now showing 1 - 4 of 4
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    Characterization of four new compounds from protea cynaroides leaves and their tyrosinase inhibitory potential
    (MDPI, 2022) Yalo, Masande; Makhaba, Masixole; Hussein, Ahmed A.
    Protea cynaroides (king protea) is a flowering plant that belongs to the Proteaceae family. This multi-stemmed shrub is the national flower of South Africa and has important economic and medicinal values. Traditionally, the main therapeutic benefits of this plant species include the treatment of cancer, bladder, and kidney ailments. There are very limited reports on the isolation of phytochemicals and their biological evaluation from P. cynaroides. In this study, the leaves of P. cynaroides were air-dried at room temperature, powdered, and extracted with 80% methanol followed by solvent fractionation (hexane, dichloromethane, ethyl acetate, and butanol). The ethyl acetate and butanol extracts were chromatographed and afforded four new (1–4) and four known (5–8) compounds, whose structures were characterized accordingly as 3,4-bis(4-hydroxybenzoyl)-1,5-anhydro-D-glucitol (1), 4-hydroxybenzoyl-1,5-anhydro-D-glucitol (2), 2-(hydroxymethyl)-4-oxo-4H-pyran-3-yl-6-O-benzoate-β-D-glucopyranoside (3), 3-hydroxy-7,8-dihydro-β-ionone 3-O-β-D-glucopyranoside (4), 4-hydroxybenzoic acid (5), 1,5-anhydro-D-glucitol (6), 3,4-dihydroxybenzoic acid (7), and 3-hydroxykojic acid (8).
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    Helichrysum genus and compound activities in the management of diabetes mellitus
    (MDPI, 2022) Akinfenwa, Akeem O.; Sagbo, Idowu J.; Makhaba, Masixole
    The global management of diabetes mellitus (DM) involves the administration of recommended anti-diabetic drugs in addition to a non-sedentary lifestyle upon diagnosis. Despite the success recorded from these synthetic drugs, the traditional method of treatment using medicinal plants is increasingly accepted by the locals due to its low cost and the perceived no side effects. Helichrysum species are used in folk medicine and are documented for the treatment of DM in different regions of the world. This study reviews Helichrysum species and its compounds’ activities in the management of DM.
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    Phytochemical and biological studies of extracts from selected South African indigenous medicinal plants: Bulbine and helichrysum species
    (University of the Western Cape, 2022) Makhaba, Masixole; Mabusela, Wilfred
    Medicinal plants from the Asteraceae and Asphodelaceae families are among the most widely recognized in South African traditional medicine for managing diabetes mellitus. Diabetes mellitus is a universal epidemic, yet there are no permanent treatments for this disease. Three South African indigenous medicinal plants, namely Helichrysum petiolare (Asteraceae), H. splendidum (Asteraceae), and Bulbine frutescens (Asphodelaceae) which have reported ethnobotanical usage in the management of diabetes were investigated in this study. Despite the increasing scientific evidence using the extracts that supports the ethnobotanical claims of these medicinal plants, the active metabolites, or their mechanism of action is not considered.
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    Phytochemical studies of extracts from Aloe succotrina
    (University of the Western Cape, 2017) Makhaba, Masixole; Mabusela, Thozamile
    Global climate change and geographical differences are two major parameters known to have, either, direct or indirect influence on the production of secondary metabolites in plants, which in-turn may affect the quality and/or quantity of the overall metabolites. The primary purpose of this thesis was to evaluate the phytochemistry of the whole leaf of Aloe succotrina Lam. spp. - a South African native plant - through a chromatographic spectroscopic approach-against available data accumulated for the cultivated population. Preliminary screening of the crude extracts i.e. HEX, DCM and EtOAc on TLC aluminium plates precoated with silica gel 60 F254 followed by various chromatographic separation, led to the isolation of five known compounds: ?-sitosterol (1) and two anthrone-C-glycosides (2 and 5), including two coumarin derivatives-the aglycone (3) and glycoside derivative (4). Notably, apart from 5 and 2, the accumulation of 1, 3 and 4 in A. succotrina Lam. spp. is reported for the first time. Structural elucidation of the individual compounds was achieved by extensive spectroscopic analysis i.e. MS, IR, 1H and 13C-NMR spectroscopy and in some cases comparison to the literature. A comparative HPLC chromatogram of the crude MeOH extract of the leaves of A. succotrina Lam. was developed for qualitative (and quantitative) identification of the active metabolites, which could be realized by VWD with detection at 290 nm.