Degradation of cell wall polysaccharides and change of related enzyme activities with fruit softening in Annona squamosa during storage

To investigate cell-wall carbohydrate metabolism and fruit softening of postharvest Annona squamosa, several indicators including firmness, moisture distribution, cell-wall polysaccharides compositions, activities of enzymes related with fruit softening during storage were studied. Results indicated that firmness exhibited a significant decline from 1 d to 3 d. Free and semi-bound moisture in pericarp was removed gradually and moisture migrated from high to low freedom degree during storage. Molecular weight distribution and monosaccharide composition of cell-wall polysaccharides changed greatly during storage, especially the degradation of pectin polysaccharide. Besides, related enzymes including PG, PME and Cx were all involved in fruit softening of postharvest Annona squamosa. This would provide theoretical basis to help solve fruit quality decline of Annona squamosa during storage in further research.