Internal browning in pear fruit (Pyrus communis L. cv Conference) may be a result of a limited availability of energy and antioxidants

Storage of pears (Pyrus communis) under hypoxia, especially in the presence of increased CO2 partial pressures, can lead to development of brown core. Disorder development, concentrations of ascorbic acid (AA) and adenosine triphosphate (ATP), and respiration were examined under various O-2 (0-21 kPa) and CO2 (0 and 5 kPa) atmospheres during 31 days of storage. ATP production was estimated using the respiration data. Hypoxia increased brown core incidence, decreased AA and ATP concentrations, and lowered ATP production. AA concentrations decreased before brown core became visible. Adding CO2 to the storage atmosphere increased the severity of brown core. CO2 addition also decreased AA levels by about 46% at O-2 partial pressures of 2.5 kPa and higher. CO2, however, had variable effects on ATP production. No brown core was found in fruit kept at 0 kPa O-2 with or without CO2, nor decreased AA levels. These results support the hypothesis that brown core initiation is a consequence of membrane damage caused by a combination of oxygen free radical action and a lack of maintenance energy. This combination may lead to decompartmentation of intracellular structures and the initiation of brown pigmentation, visible in pears with disorders. (C) 2002 Elsevier Science B.V. All rights reserved.

[1]  C. Bailly,et al.  Changes in malondialdehyde content and in superoxide dismutase, catalase and glutathione reductase activities in sunflower seeds as related to deterioration during accelerated aging , 1996 .

[2]  Shu-sen Liu,et al.  Generating, Partitioning, Targeting and Functioning of Superoxide in Mitochondria , 1997, Bioscience reports.

[3]  F. Bangerth,et al.  Effect of high CO2 and controlled atmosphere (CA) on the ascorbic and dehydroascorbic acid content of some berry fruits , 1997 .

[4]  R. Kho,et al.  Ascorbic acid and tissue browning in pears (Pyrus communis L. cvs Rocha and Conference) under controlled atmosphere conditions. , 2000 .

[5]  G. M. Walton,et al.  Adenosine triphosphate conservation in metabolic regulation. Rat liver citrate cleavage enzyme. , 1967, The Journal of biological chemistry.

[6]  M. Vendrell,et al.  Harvest date affects the antioxidative systems in pear fruits , 1999 .

[7]  N. R. Knowles,et al.  Oxidative Stress Results in Increased Sinks for Metabolic Energy during Aging and Sprouting of Potato Seed-Tubers , 1996, Plant physiology.

[8]  L. A. Río,et al.  Evidence for the Presence of the Ascorbate-Glutathione Cycle in Mitochondria and Peroxisomes of Pea Leaves , 1997, Plant physiology.

[9]  Stefan Persijn,et al.  Decreased ascorbic acid levels and brown core development in pears (Pyrus communis L. cv. Conference) , 1999 .

[10]  R. Veltman,et al.  PPO Activity and Polyphenol Content are not Limiting Factors During Brown Core Development in Pears (Pyrus communis L. cv. Conference) , 1999 .

[11]  M. E. Patterson,et al.  Storage effects on fruits. Nonvolatile organic acids and core breakdown of Bartlett pears. , 1964 .

[12]  M. Ribas-Carbó,et al.  Direct Inhibition of Plant Mitochondrial Respiration by Elevated CO2 , 1996, Plant physiology.

[13]  A. C. Hulme.  Carbon Dioxide Injury and the Presence of Succinic Acid in Apples , 1956, Nature.

[14]  E. Woltering,et al.  Carbon dioxide and 1-MCP inhibit ethylene production and respiration of pear fruit by different mechanisms , 1999 .

[15]  R. Rabbinge,et al.  Respiratory characteristics and calculated ATP production of apple fruit in relation to tolerance of low O2 concentrations. , 1996 .

[16]  Pavelic,et al.  Membrane lipid integrity relies on a threshold of ATP production rate in potato cell cultures submitted to anoxia , 1999, Plant physiology.

[17]  A. Kader,et al.  Effects of Elevated CO(2) Concentrations on Glycolysis in Intact ;Bartlett' Pear Fruit. , 1988, Plant physiology.

[18]  H. W. Peppelenbos,et al.  A theoretical approach on the role of fermentation in harvested plant products , 1998 .

[19]  R. Dhindsa,et al.  Leaf Senescence: Correlated with Increased Levels of Membrane Permeability and Lipid Peroxidation, and Decreased Levels of Superoxide Dismutase and Catalase , 1981 .

[20]  S. Yamaki.  Isolation of Vacuoles from Immature Apple Fruit Flesh and Compartmentation of Sugars, Organic Acids, Phenolic Compounds and Amino Acids , 1984 .