Further Obervations on the Use of the Medicinal Plant, Vernonia amygdalina (Del). By a Wild Chimpanzee, Its Possible Effect on Parasote Load, and Its Phytochemistry

Abstract

This is the second detailed case study of the use of V. amygdalina (Del) by a wild chimpanzee suffering from gastrointestinal upset (flatulence and diarrhea). The female, who was followed for approximately 5 hours over a two-day period, recovered from her symptoms by the afternoon of the second day. Laboratory examination of two decal samples, one collected approximately 1 hour and another 20.5 hours after ingestion of the plant's bitter pith, revealed a notable drop in the degree of parasitic infection by a Ternidens sp. Bioassay of the plant consumed by the female confirmed that the two most abundant and bioactive constituents, vernodalin and vernonioside B1, were present. Vernonioside B1 was found to occur at significant levels in both the leaves and pith, but the cytotoxic vernodalin was found only in the leaves. This suggests that vernonioside B1 and its naturally occurring aglycones are likely to be the bioactive constituents ingested by chimpanzees. The estimated amount of vernonioside B1 ingested by this female was found to be approximately equal to the amount contained in a traditional Tongwe medicinal preparation from a cold water extract of the leaves to treat similar gastrointestinal disorders in adult human patients. This report provides new evidence for the effectiveness of medicinal plant use in primates and strongly supports the current hypothesis regarding the use of V. amygdalina for the control of symptoms from parasitic and gastrointestinal illness by wild chimpanzees.