Partager

Activités de plusieurs hydrolases de la membrane et de la paroi cellulaire, activité des enzymes biosynthétiques d'éthylène et baisse de la teneur en polyuronide de la paroi cellulaire au cours de l'entreposage de papayes (Carica papaya) intactes ou fraîchement coupées.

Activities of several membrane and cell-wall hydrolases, ethylene biosynthetic enzymes, and cell wall polyuronide degradation during low-temperature storage of intact and fresh-cut papaya (Carica papaya) fruit.

Auteurs : KARAKURT Y., HUBER D. J.

Type d'article : Article

Résumé

Fresh-cut fruit tissue deteriorates more rapidly than its intact counterpart. A study was conducted to determine changes in firmness, cell-wall polyuronides, and the activities of cell-wall and membrane hydrolases and ethylene biosynthetic enzymes in intact and fresh-cut papaya fruit during storage at 5 °C. Processing of papaya fruit was performed at 5 °C, and fruit pieces were stored for 8 days at 5 °C. Levels of total and CDTA-soluble polyuronides in intact fruit did not change during storage, but water-soluble polyuronides increased significantly by day 8 (15%). In contrast, total polyuronide content of fresh-cut papaya decreased (9.5%), whereas levels of CDTA- and water-soluble polyuronides increased 45 and 30%, respectively. Firmness and mol mass of polyuronides decreased more rapidly in fresh-cut fruit than in intact fruit. The activities of polygalacturonase, alpha- and beta-galactosidases, lipoxygenase, phospholipase D, and ACC synthase) and ACC oxidase increased within 24 h in fresh-cut fruit, and remained significantly higher compared with levels in intact fruit throughout storage. Pectin methyl esterase, and phospholipase C activities showed no consistent differences between fresh-cut and intact fruit. The data suggest that a wound-induced increase in enzymes targeting cell walls and membranes contributes to the rapid deterioration of fresh-cut fruit. The significantly less pronounced changes observed for intact fruit stored under identical conditions indicate that the enhanced deterioration of fresh-cut fruit does not reflect low-temperature injury.

Détails

  • Titre original : Activities of several membrane and cell-wall hydrolases, ethylene biosynthetic enzymes, and cell wall polyuronide degradation during low-temperature storage of intact and fresh-cut papaya (Carica papaya) fruit.
  • Identifiant de la fiche : 2004-0201
  • Langues : Anglais
  • Source : Postharvest Biol. Technol. - vol. 28 - n. 2
  • Date d'édition : 05/2003

Liens


Voir d'autres articles du même numéro (2)
Voir la source

Indexation