Phenolic acids and flavonoids of Theobroma cacao L. Separation and identification by paper chromatography

Abstract

The distribution of phenolic compounds in the tissues of Theobroma cacao is described. Leucocyanidine L1 and L2 and (-)-epicatechin were present to a varying degree in all tissues. Caffeic acid, p-coumaric acid and an unidentified fluorescent compound of Rf 0.28 are present in many cacao tissues, but ferulic and sinapic acids are of limited occurrence. The major anthocyanin of the young leaf and young pod wall was shown to be 3-a-L-arabinosidyl-cyanidin, and in the flower 3-a-L-arabinosidylcyanidin and 3-B-D-galactosidylcyanidin were present in approximately equal amounts. Cyanidin hydrochloride was the only anthocyanidin detected in tissue hydrolysates of T. cacao. p-Coumarylquinic acid was detected in the cotyledons of the bean and in young-leaf tissue. Chlorogenic acid was also shown to occur in young leaf tissue. A fluorescent phenolic compound releasing caffeic acid on hydrolysis, but not identical with chlorogenic or isochlorogenic acid, was detected in pod-wall tissue. Leucocyanidin material is present in large amounts in young leaf tissue but the content falls to a very low level at maturity. Similar developmental changes were observed in pod-wall tissue.