|Chen, Hangjun -|
Submitted to: Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 19, 2010
Publication Date: January 1, 2011
Citation: Wang, S.Y., Chen, H., Ehlenfeldt, M.K. 2011. Variation in antioxidant enzyme activities and nonenzyme components among cultivars of rabbiteye blueberries (Vaccinium ashei Reade) and V. ashei derivatives. Food Chemistry. 120:13-20. Interpretive Summary: Blueberries generally contain high antioxidant enzyme activities and high levels of antioxidants that are associated with improved human health. However, different cultivars of blueberries vary greatly in their antioxidant enzyme activities. In order to select genotypes with highest antioxidant enzyme levels for use in breeding programs to develop new cultivars, we screened 42 blueberry cultivars that included 36 rabbiteye blueberries, three northern highbush blueberries and 3 related hybrids for their antioxidant enzyme activities. We found that several rabbiteye cultivars and northern highbush types had the highest antioxidant enzyme activity. These blueberry cultivars can possibly be used in future blueberry breeding to develop new improved blueberry cultivars with higher antioxidant enzyme activity. This information is useful to consumers, growers, and blueberry industry.
Technical Abstract: Fruit from forty-two blueberry (Vaccinium species) cultivars, including thirty-six rabbiteye rabbiteye cultivars (Vaccinium ashei Reade), three V. ashei hybrid derivatives and three northern highbush (V. corymbosum L.) standards were evaluated for antioxidant activities (AA), levels of antioxidant enzymes [catalase (CAT), ascorbate peroxidase (AsA-POD), glutathione reductase (GR), glutathione peroxidase (GSH-POD), superoxide dismutase (SOD), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDAR), and guaiacol peroxidase (G-POD)], and anthioxidant nonenzyme components [ascorbic acid (ASA) and glutathione (GSH)]. The results of this study showed that cultivars had varying levels of AA, a wide range of antioxidant enzyme activities, and various amounts of nonenzyme components. The correlations between AA and all of the enzyme activities or nonenzyme components were positive and high in the forty-two cultivars tested in this study. The correlation (R2) values between AA and CAT, SOD, DHAR, MDAR, GSH-POD, GR, G-POD, and AsA-POD were 0.91, 0.91, 0.91, 0.91, 0.90, 0.90, 0.90, and 0.90, respectively. The correlations between AA and ASA and GSH were 0.94 and 0.92, respectively. Among all 42 cultivars, ‘Early May’ had the highest activities of the AA, AsA-POD, G-POD, DHAR, and MDAR; and the highest amounts of ASA and GSH; whereas ‘Elliott’ had highest levels of GR, GSH and SOD. The cultivars with high antioxidants and antioxidant enzyme activities may be especially useful in a breeding program for developing more nutritious blueberry varieties with improved health-promoting quality for consumers.