Occurrence of γ-Linolenic Acid in Ranunculaceae Seed Oils

Abstract

gamma-Linolenic acid has been found in the seed oils of a number of plants, but its distribution in the various plant genera and plant families is not well understood. These oils, e.g. borage oil and evening primrose oil, have found considerable interest for pharmaceutical and dietary use. Our investigation of the seed lipids of Ranunculaceae has shown the presence of unusual fatty acids, including considerable amounts (up to 20 %) of gamma-linolenic acid in three genera of the Anemonoideae (Anemone, Clematis and Atragene). It was present in four species of Anemone, whereas this acid was absent in four other species of Anemone. Among the Anemonoideae sensu Takhtajan, gamma-linolenic acid was definitely absent in Caltha and Pulsa-tilla. It is interesting to note that Delta 5cis and Delta 5trans fatty acids had been reported to occur in significant percentages in the seed oils of other members of the same plant family, where gamma-linolenic acid, a Delta 6cis-acid, has now been found. gamma-Linolenic acid thus seems to be much more widely distributed throughout the plant kingdom. It has now been demonstrated to be present in at least 10 different plant families.