CALENDIC ACID IN SEED OILS OF THE GENUS CALENDULA
Seed oils of 17 definite and putative species of Calendula were examined. The major fatty acid of C. arvensis oil was identified as trans-8, trans-10, cis-12-octadecatrienoic acid (calendic acid). Spectrometric evidence demonstrated that all 17 species contained the same acid, in amounts varying from 38.9 to 58.4% of the oil.Seed was collected at intervals during maturation from growing plants of C. officinalis. Analysis of the seed and the oil showed that the conjugated trienoic acid was present at an early stage of development and increased steadily in amount to maturity. Accumulation of hydroxydienoic or conjugated dienoic acid in quantity was not observed at any stage although small amounts may have been present. It is concluded that calendic acid is formed in the seed by a rapid continuous process.