Publications

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Bassey, K., Viljoen, A., Combrinck, S., Choi, Y.H. 2014. New phytochemicals from the corms of medicinally important South African Hypoxis species. Phytochemistry Letters 10: lxix-lxxv.

Hypoxis species (Hypoxidaceae) are amongst the most widely used medicinal plants in southern Africa. Although the phytochemistry of Hypoxis hemerocallidea has been extensively investigated, little is known regarding the secondary metabolites of the other indigenous species, including Hypoxis colchicifolia andHypoxis galpinii. Two new phenolic glycosides, 3-hydroxy-4-O-β-D-glucopyranosylbenzaldehyde and 1,5-bis(3,4-dihydroxyphenyl)-1,2-dihydroxy-4-pentyne-2-p-coumaroyl-b-D-glucopyranoside were isolated from corms of H. colchicifolia and H. galpinii, respectively. The norlignan glycosides (hypoxoside, dehydroxy hypoxoside and bis-dehydroxy hypoxoside) were isolated from H.colchicifolia for the first time, using high performance counter current chromatography and elucidated by 1D and 2D NMR as well as high resolution MS. In addition, geraniol glycoside and β-sitosterol, previously described in Hypoxidaceae, were isolated from the same species. The presence of hypoxoside in all three species investigated indicated that the interchangeable use of Hypoxis species by communities has some merit. Establishing the biological properties of the new constituents will provide more insight into the medicinal value of the genus.



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