Location: Plant Genetic Resources ResearchTitle: Characterization of Nutritionally Important Carotenoids in Welsh Onion Accessions Author
Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/25/2010
Publication Date: 3/15/2010
Citation: Kopsell, D.A., Carl, S., Deyton, D., Abney, K., Kopsell, D., Robertson, L.D. 2010. Characterization of Nutritionally Important Carotenoids in Welsh Onion Accessions. HortScience. 45(3):463-465. Interpretive Summary: Bunching onion (Allium fistulosum) is commonly used in Asian cuisine as a vegetable, where the entire plant is consumed. Bunching onion contains important plant chemicals (carotenoids and chlorophylls) which are recognized as important in human health. The goal of this study was to characterize these phytochemicals and to identify the influence of genes and the environment on their variation of bunching onions. Twelve accessions of bunching onions were grown at Knoxville, TN and Geneva, NY during the summer of 2007 and plant samples were evaluated for these pigments. We found no important differences between locations or accessions for carotenoids or chlorophylls indicating that the twelve accessions were closely related or that selection for the twelve accessions was based on flavor attributes and not these pigments.
Technical Abstract: Members of the Allium genus are consumed for their culinary flavor attributes, but also contain antioxidant and anticarcinogenic phytochemicals. Welsh onions (Allium fistulosum L.) are commonly used in Asian cuisine, where both leaves and pseudostems are consumed. Carotenoids are an important class of phytochemical gaining attention for their health attributes. The goal of our study was to characterize carotenoids and chlorophylls present in leaf tissues, and to indentify genetic and environmental differences in carotenoid concentrations among A. fistulosum accessions. Twelve USDA-ARS accessions were field grown in Knoxville, Tenn. and Geneva, N.Y. during the summer of 2007. After harvest, carotenoid and chlorophyll pigments were evaluated in leaf and pseudostem tissues using HPLC methodology. We were able to identify the presence of antheraxanthin, ß-carotene, lutein, neoxanthin, and violaxanthin in leaf tissues; however, pigments were not found in pseudostem tissues. Carotenoid and chlorophyll concentrations did not differ between locations or among accessions. It is possible that accessions evaluated in this study are genetically closely related, or were selected based on flavor attributes and not leaf tissues pigmentations.