STUDIES ON HYPOXOSIDE AND ROOPEROL ANALOGS FROM HYPOXIS-ROOPERI AND HYPOXIS-LATIFOLIA AND THEIR BIOTRANSFORMATION IN MAN BY USING HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH IN-LINE SORPTION ENRICHMENT AND DIODE-ARRAY DETECTION

Methanol extracts of the corms of Hypoxis rooperi and H. latifolia wer e studied for their hypoxoside content by an in-line sorption enrichme nt HPLC technique [Kruger et al., J. Chromatogr, 612 (1993) 191]. Hypo xoside is the trivial name for bis(3'-hydroxy-4'-0-beta-D-glucopyranos yyl-phenyl) pent-1-en-4-yne and rooperol the aglucone obtained from be ta-glucosidase treatment. Hypoxoside and rooperol analogues containing 4, 3 and 2 hydroxyl groups resolved as separate peaks with the propor tion of the latter two markedly higher in H. latifolia than in H. roop eri. After oral ingestion of hypoxoside by humans, no hypoxoside or ro operol appeared in the serum. Only rooperol was present in the faeces. The serum and urine contained at least three phase II metabolite peak s. Selective enzyme hydrolysis showed that they represent the diglucur onide, disulfate and glucuronide-sulfate conjugates of all three roope rol analogues.