Abstract
Compared to control longan, DCC-treated longan had higher pulp breakdown index, lower ATP, ADP and EC levels, and lower H(+), Ca(2+) and Mg(2+)-ATPase activities. On day 6, DCC-treated longan presented 18% higher pulp breakdown index, with 44%, 9% and 31% lower levels of ATP, ADP and EC, respectively. Additionally, DCC-treated longan showed 29%, 53%, 37% lower activity of H(+)-ATPase, 34%, 54%, 4% lower activity of Ca(2+)-ATPase, and 13%, 21%, 6% lower activity of Mg(2+)-ATPase in the membranes of plasma, vacuole, and mitochondria, respectively. Whereas, DS-treated longan manifested the opposite trends of DCC treatment. These results suggest that the accelerated pulp breakdown in DCC-treated longan was linked to energy deficiency and reduced energy production. However, DS treatment restrained pulp breakdown occurrence in fresh longan by maintaining a higher energy level through the elevated energy production and ATPase activity.