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Evdokia Menelaou, Armen Kachatryan, Jack N. Losso, Michael Cavalier, and Don La Bonte

Fresh leaves of 6 sweetpotato (Ipomoea batatas [L.] Lam.) genotypes, `Beauregard', `Bienville', L99–35, L00–8, L01–145, and L01–29, were characterized for lutein. Lutein is a carotenoid capable of delaying blindness-related macular degeneration. The content of lutein in sweetpotato ranged from 0.38 to 0.58 mg·g–1 fresh weight. Beta-carotene separated from lutein on high-pressure liquid chromatograms and when spiked in pure lutein extract did not interfere with lutein separation. High-resolution electro-spray ionization mass spectrometric analysis was used to confirm the presence of lutein in sweetpotato leaves. Stems were also characterized and found not to contain lutein. Our results showed that sweetpotato leaves are an excellent source of dietary lutein and surpass levels found in leafy crucifers. Leaves of sweetpotato and a related species are human food in some countries and may be a major source of lutein for commercial purposes.

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Michael Cavalier, Armen Kachatryan, Evodokia Menelaou, Jack Losso, and Don LaBonte

Fresh leaves of six sweetpotato [Ipomoea batatas (L.) Lam.] genotypes, `Beauregard', `Bienville', L 99-35, L 00-8, L 01-145, and L 01-29 were characterized for lutein. Lutein is a carotenoid capable of delaying blindness-related macular degeneration. The content of lutein in sweetpotato ranged from 0.38 to 0.58 mg·g-1 fresh weight. Beta-carotene separated from lutein on HPLC chromatograms, and, when spiked in pure lutein extract, did not interfere with lutein separation. Stems were also characterized and found not to contain lutein. Our results showed that sweetpotato leaves are an excellent source of dietary lutein and surpass levels found in leafy crucifers. Leaves of sweetpotato and a related species are used as human food in some countries and could be a source of extracted lutein for commercial purposes.

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Beiquan Mou

There is increasing medical evidence for the health benefits derived from dietary intake of carotenoid antioxidants, such as β-carotene and lutein. Enhancing the nutritional levels of vegetables would improve the nutrient intake without requiring an increase in consumption. A breeding program to improve the nutritional quality of lettuce (Lactuca sativa L.) must start with an assessment of the existing genetic variation. To assess the genetic variability in carotenoid contents, 52 genotypes including crisphead, leaf, romaine, butterhead, primitive, Latin, and stem lettuces, and wild species were planted in the field in Salinas, Calif., in the Summer and Fall of 2003 with four replications. Duplicate samples from each plot were analyzed for chlorophyll (a and b), β-carotene, and lutein concentrations by high-performance liquid chromatography (HPLC). Wild accessions (L. serriola L., L. saligna L., L. virosa L., and primitive form) had higher β-carotene and lutein concentrations than cultivated lettuces, mainly due to the lower moisture content of wild lettuces. Among major types of cultivated lettuce, carotenoid concentration followed the order of: green leaf or romaine > red leaf > butterhead > crisphead. There was significant genetic variation in carotenoid concentration within each of these lettuce types. Crisphead lettuce accumulated more lutein than β-carotene, while other lettuce types had more β-carotene than lutein. Carotenoid concentration was higher in summer than in the fall, but was not affected by the position of the plant on the raised bed. Beta-carotene and lutein concentrations were highly correlated, suggesting that their levels could be enhanced simultaneously. Beta-carotene and lutein concentrations were both highly correlated with chlorophyll a, chlorophyll b, and total chlorophyll concentrations, suggesting that carotenoid content could be selected indirectly through chlorophyll or color measurement. These results suggest that genetic improvement of carotenoid levels in lettuce is feasible.

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Mark G. Lefsrud, Dean A. Kopsell, and Carl E. Sams

Huner, 2004 ). The carotenoid pigments lutein (L) and β-carotene (BC) absorb strongly in the blue region with maximum absorption occurring at 448 and 454 nm (in acetone), respectively ( Hopkins and Huner, 2004 ). Previously, maximum biosynthesis of plant

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Dean A. Kopsell, David E. Kopsell, Mark G. Lefsrud, Joanne Curran-Celentano, and Laura E. Dukach

Green leafy vegetables are important sources of dietary carotenoids, and members of Brassica oleracea L. var. acephala rank highest for reported levels of lutein and β-carotene. Twenty-three leafy B. oleracea cultigens were field grown under similar fertility over two separate years and evaluated for leaf lutein and β-carotene accumulation. Choice of B. oleracea cultigen and year significantly affected carotenoid levels. Lutein concentrations ranged from a high of 13.43 mg per 100 g fresh weight (FW) for B. oleracea var. acephala `Toscano' to a low of 4.84 mg/100 g FW for B. oleracea var. acephala 343-93G1. β-carotene accumulations ranged from a high of 10.00 mg/100 g FW for B. oleracea var. acephala `Toscano' to a low of 3.82 mg/100 g FW for B. oleracea var. acephala 30343-93G1. Carotenoid concentrations were significantly higher in year 2 than in year 1, but rank order among the cultigens for both lutein and ß-carotene did not change between the years. During each year, there were high correlations between leaf carotenoid and chlorophyll pigments. Under similar growing conditions, choice of B. oleracea cultigen will influence carotenoid accumulation, and this may affect the health benefits of consuming these leafy green vegetable crops.

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Jennifer Bonina-Noseworthy, J. Brent Loy, Joanne Curran-Celentano, Rebecca Sideman, and Dean A. Kopsell

precursors to vitamin A, which has a significant role in vision, in maintaining a healthy immune system, and in regulation of gene expression during growth and development ( Britton, 2009 ). Two xanthophylls, lutein and zeaxanthin, are present in the retina

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Mark W. Farnham and Dean A. Kopsell

lutein (3R,3′R,6′β,ɛ−carotene-3,3′diol), an oxygenated xanthophyll, and β-carotene (β,β−carotene), a hydrocarbon carotene. β-carotene and also zeaxanthin, antheraxanthin, violaxanthin, and neoxanthin are a group of carotenoids that contain two β

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Dean A. Kopsell, Kimberly J. Whitlock, Carl E. Sams, and David E. Kopsell

and tissue concentrations of lutein and zeaxanthin and macular pigment density Amer. J. Clin. Nutr. 71 1555 1562 Kopsell, D.A. Kopsell, D.E. Lefsrud, M.G. Curran-Celentano, J. Dukach, L.E. 2004 Variation in lutein, β-carotene, and chlorophyll

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T. Casey Barickman, Dean A. Kopsell, and Carl E. Sams

and form J. Sci. Food Agr. 87 900 907 Kopsell, D.A. Kopsell, D.E. Lefsrud, M.G. Curran-Celentano, J. Dukach, L.E. 2004 Variation in lutein, beta-carotene, and chlorophyll concentrations among Brassica oleracea cultigens and seasons HortScience 39 361

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Mark Lefsrud, Dean Kopsell, Carl Sams, Jim Wills, and A.J. Both

significant decrease in lutein and β-carotene was measured in daylily ( Hemerocallis disticha Donn ex Sweet) when oven dried at 48 °C compared with −53 °C freeze drying ( Tai and Chen, 2000 ). Cinar (2004) reported that freeze drying reduced the losses of