RELATIONSHIP BETWEEN ACID INVERTASE ACTIVITY AND SUGAR CONTENT IN GRAPE SPECIES

• Author(s): Basha, SM; Kambiranda, D; Vasanthaiah, H;
• Abstract: Among grape species muscadines are the important grape crops of the southeastern United States, where cultivation of Vitis vinifera is limited due to Pierce's disease. Muscadine grapes are less desirable because of their low sugar content and leathery skin. Sugar accumulation in berry depends on the activity of sugar metabolizing enzymes during ripening. The present study was carried out to investigate differences in invertase activity among Muscadinia rotundifolia (Muscadine), Vitis spp. (Florida hybrid bunch) and V. vinifera (Bunch) grape genotypes and to characterize muscadine invertase/s. Bunch grape showed highest invertase activity followed by Florida hybrid bunch and muscadine. Muscadine invertase showed a pH optimum between 2.5 and 3.5 and substrate optimum at 150 mM. These data suggest that low sugar content of muscadine berry may be related to its low invertase activity, and enhancement of invertase activity may be one way to increase the sugar content of muscadine grape.
• Publication Date: Dec 2011
• Journal: Journal Of Food Biochemistry