ISHS Acta Horticulturae 681: IV International Congress on Artichoke
PHARMACEUTICALLY RELEVANT PHENOLIC CONSTITUENTS IN ARTICHOKE LEAVES ARE USEFUL FOR CHEMICAL CLASSIFICATION OF ACCESSIONS |
| Authors: | D. Wagenbreth, J. Eich |
| Keywords: | Cynara, caffeoylquinic acids, flavonoids, chemotype |
| Abstract:
Plants of 30 accessions of artichoke and cardoon (Cynara cardunculus L. cv. scolymus and cv. cardunculus) which were grown from seeds annually were cultivated in field plots in Eastern Germany from 1994 to 1996. Dried leaflets (pinna) of adult leafs were analyzed by HPLC regarding the occurrence and content of caffeoyl quinic acids (CQA) and flavonoids. The content of total CQA varied from 5 to 9 % with chlorogenic acid (CA) and 1,3-di-CQA as main components. The total flavonoids ranged from 0.3 to 1.2 %. Cynaroside, scolymoside, and the recently identified compound luteolin-7-O-  -glucuronide (L7G) were found in the flavonoid fraction.
The flavonoid patterns permit classification of the accessions into 4 chemotypes: Type I = cynaroside and scolymoside were present, L7G absent; Type II = cynaroside and L7G were present, scolymoside absent; Type III = all three flavonoids (cynaroside, scolymoside, L7G) were present; Type IV = only cynaroside was detectable.
The 30 accessions of artichoke (A) and cardoon (C) were distributed among the 4 chemotypes as follows: I = 7A, II = 2A and 8C, III = 10A and 1C, IV = 1A and 1C. The accessions were not completely homogeneous regarding their chemical constituents, because single plants may correspond to another chemotype.
The accessions of type III may be considered as hybrids of types I and II. The content of total CQA and flavonoids was higher in the types II and IV compared to that of type I. A higher quotient CA/1,3-di-CQA was found for types I and III than for types II and IV. Internal and external factors (content gradients within the plant, low temperatures) influenced the content of the constituents examined.
Nevertheless, the chemotypes could also be distinguished from each other in such cases.
| |
Download Adobe Acrobat Reader (free software to read PDF files) | |
