Plant species with unusual taste properties such as bitterness, sourness or sweetness, and others with a taste-modifying component, have long been known to man, although their exploitation has been limited (Inglett and May, 1968). As there are several limiting taste qualities to commercially available sweeteners (Rader et al., 1967), a superior synthetic compound could readily expand the present sweetener market (Inglett and May, 1969). The recent restriction on the use of artificial sweeteners such as cyclamate in the U.S.A. and other countries highlights the commercial potential for indigenous plant species with taste-modifying properties or sweetening principles (Adansi, 1970). A harmless, non-caloric, acceptable sweetener has great potential as an alternative to traditional carbohydrate sweeteners (Nordsiek, 1972; Anon, 1973). An alternative to the organic synthesis of analogues of known compounds is to screen tropical plant material (usually the fruit) for new naturally occurring intense sweetness. Dioscoreophyllum cumminsii, the 'Serendipity Berry' (Family Menispermaceae) is a dioecious, herbaceous perennial species indigenous to tropical West Africa. The plant has long, thin, twining stems and grows in the humid and heavily shaded understory vegetation of closed forests. The aerial vegetation dies back in the end-of-the year dry season and tubers resprout to produce climbing vines at the onset of the rains (around mid-