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Published on: November 6, 2021
Microsomal Membrane Changes during the Ripening of Apple Fruit
1Division of Fruit and Vegetable Storage, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel.
Plant Physiology
|November 1, 1983
Summary
Apple ripening involves significant changes in microsomal membrane properties, particularly at the climacteric stage. These shifts correlate with alterations in lipid composition, including sterols and phospholipids, impacting membrane fluidity and function.
Area of Science:
- Plant Physiology
- Biochemistry
- Membrane Biology
Background:
- Microsomal membranes play a crucial role in cellular functions and are sensitive to developmental changes.
- Fruit ripening involves complex biochemical and physical alterations within plant cells.
Purpose of the Study:
- To investigate the relationship between apple (Malus sylvestris) ripening stages and changes in microsomal membrane properties.
- To correlate these membrane property changes with alterations in lipid composition, specifically sterols, phospholipids, and fatty acids.
Main Methods:
- Analysis of microsomal membranes isolated from apples at various ripening stages.
- Measurement of membrane properties such as leakage and viscosity.
- Quantification of lipid components: sterols, phospholipids, and fatty acids of phospholipids.
Main Results:
- Significant changes in membrane leakage and viscosity were observed during apple ripening.
- The most pronounced alterations in membrane properties occurred at the climacteric stage.
- A notable shift in the sterol:phospholipid ratio coincided with the climacteric peak.
- Changes in fatty acid unsaturation levels were primarily observed in the post-climacteric phase.
Conclusions:
- Apple ripening significantly impacts microsomal membrane biophysical properties.
- Lipid composition, particularly the sterol:phospholipid ratio, is a key determinant of membrane changes during ripening.
- Fatty acid unsaturation plays a role in later stages of ripening, influencing membrane fluidity.
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