Respiratory Activity And Morphology of Mitochondria Isolated from Whole and Sliced Storage Tissue

Abstract

Mitochondria isolated from whole tissue and from freshly sliced and aged disks of beetroot [Beta vulgaris] and swedes [Brassica napo-brassica] were tested for their oxidative capacity and their morphology was compared by electron microscopy. Mitochondria isolated from whole tissue were active and structurally intact, while mitochondria obtained by the same procedure from freshly sliced tissue were inactive and had disintegrated. A partial recovery of oxidative capacity and structural intactness occurred after "aging" of the tissue slices. These findings were considered in relation to the "lag phase" in the capacity for salt uptake in tissue slices. An increase in activity and structural intactness of mitochondria from tissue slices was obtained by adding 1% bovine serum albumin to the extraction medium. Changes in mitochondrial stability were considered in relation to the dispersal of fatty acids in the cytoplasm caused by wound effects, and the possiblity of changes in mitochondrial population due to the formation of new mitochondria during the aging of tissue slices were discussed.