Fruit Composition of Elderberry (Sambucus spp.) Genotypes Grown in Oregon and Missouri, USA.

Twelve Sambucus nigra subsp. canadensis genotypes were grown at two Missouri and one Oregon (USA) locations to characterize fruit composition in 2004, 2005, and 2006. Fruit was also sampled from an additional 10 genotypes of subsp. canadensis and nigra grown in Oregon. Soluble solids content ranged from 8.9 to 12.5 °Brix, and titratable acid (as citric acid) was 0.4 to 1.7 g/100ml. Ferric ion reducing activity potential (FRAP) values were 15.6 to 30.7 µmol/g trolox equivalents. Total anthocyanin content ranged from 85 to 385 mg/100 g cyanidin-3-glucoside equivalents (C3GE) and total phenolic content was 421 to 719 mg/100 g gallic acid equivalents (GAE). Of the genotypes sampled in three locations, six genotypes were high (250-350), and four were very low in total anthocyanin (<150 mg/100 g C3GE), respectively. 'Barn' and 'Scotia' were highest, and 'Nova' lowest in total anthocyanin content among genotypes grown in Oregon. Of the total antioxidant tests used, total phenolics was the best quick test, as it is the easiest of the assays, showed the least change among years, and correlated highly with FRAP.

Effects of deoxynivalenol on content of chloroplast pigments in barley leaf tissues.

To understand further the role of deoxynivalenol (DON) in development of Fusarium head blight (FHB), we investigated effects of the toxin on uninfected barley tissues. Leaf segments, 1 to 1.2 cm long, partially stripped of epidermis were floated with exposed mesophyll in contact with DON solutions. In initial experiments with the leaf segments incubated in light, DON at 30 to 90 ppm turned portions of stripped tissues white after 48 to 96 h. The bleaching effect was greatly enhanced by addition of 1 to 10 mM Ca(2+), so that DON at 10 to 30 ppm turned virtually all stripped tissues white within 48 h. Content of chlorophylls a and b and of total carotenoid pigment was reduced. Loss of electrolytes and uptake of Evans blue indicated that DON had a toxic effect, damaging plasmalemmas in treated tissues before chloroplasts began to lose pigment. When incubated in the dark, leaf segments also lost electrolytes, indicating DON was toxic although the tissues remained green. Thus, loss of chlorophyll in light was due to photobleaching and was a secondary effect of DON, not required for toxicity. In contrast to bleaching effects, some DON treatments that were not toxic kept tissues green without bleaching or other signs of injury, indicating senescence was delayed compared with slow yellowing of untreated leaf segments. Cycloheximide, which like DON, inhibits protein synthesis, also bleached some tissues and delayed senescence of others. Thus, the effects of DON probably relate to its ability to inhibit protein synthesis. With respect to FHB, the results suggest DON may have multiple roles in host cells of infected head tissues, including delayed senescence in early stages of infection and contributing to bleaching and death of cells in later stages.

Rapid method for total carotenoid detection in canary yellow-fleshed watermelon.

Yellow-fleshed watermelons (Citrullus lanatus[Thunb.] Matsum. and Nakai) contain many different carotenoids, all in low to trace amounts. Since there is not 1 predominant carotenoid in yellow-fleshed watermelon, testing the total carotenoid content among watermelon lines is important in determining the antioxidant potential and thus potential health benefits of different varieties. Unfortunately, current methods to assay total carotenoid content are time consuming and require organic solvents. This report describes a rapid and reliable light absorption method to assay total carotenoid content for yellow-fleshed watermelon that does not require organic solvents. Light absorption of 78 watermelon flesh purees was measured with a diode array xenon flash spectrophotometer that can measure actual light absorption from opaque samples; results were compared with a hexane extraction method. The puree absorbance method gave a linear relationship (R(2)= 0.88) to total carotenoid content and was independent of watermelon variety within the total carotenoid concentration range measured (0 to 7 mug/g fresh weight).

Lycopene from two food sources does not affect antioxidant or cholesterol status of middle-aged adults.

BACKGROUND: Epidemiological studies have reported associations between reduced cardiovascular disease and diets rich in tomato and/or lycopene. Intervention studies have shown that lycopene-containing foods may reduce cholesterol levels and lipid peroxidation, factors implicated in the initiation of cardiovascular disease. The objective of this study was to determine whether consumption of lycopene rich foods conferred cardiovascular protection to middle-aged adults as indicated by plasma lipid concentrations and measures of ex vivo antioxidants. METHODS: Ten healthy men and women consumed a low lycopene diet with no added lycopene (control treatment) or supplemented with watermelon or tomato juice each containing 20 mg lycopene. Subjects consumed each treatment for three weeks in a crossover design. Plasma, collected weekly was analyzed for total cholesterol, high density lipoprotein cholesterol (HDL-C) and triglyceride concentrations and for the antioxidant biomarkers of malondialdehyde formation products (MDA), plasma glutathione peroxidase (GPX) and ferric reducing ability of plasma (FRAP). Data were analyzed using Proc Mixed Procedure and associations between antioxidant and lipid measures were identified by Pearson's product moment correlation analysis. RESULTS: Compared to the control diet, the lycopene-containing foods did not affect plasma lipid concentrations or antioxidant biomarkers. Women had higher total cholesterol, HDL-C and triglyceride concentrations than did the men. Total cholesterol was positively correlated to MDA and FRAP while HDL-C was positively correlated to MDA and GPX. GPX was negatively correlated to triglyceride concentration. CONCLUSIONS: The inclusion of watermelon or tomato juice containing 20 mg lycopene did not affect plasma lipid concentrations or antioxidant status of healthy subjects. However, plasma cholesterol levels impacted the results of MDA and FRAP antioxidant tests.