Skip to main content
ARS Home » Research » Publications at this Location » Publication #112884
Title: CHANGES IN OXYGEN SCAVENGING SYSTEMS AND MEMBRANE LIPID PEROXIDATION DURING MATURATION AND RIPENING IN BLACKBERRY

Author
item Wang, Shiow
item JIAO, HONGJUN - GUANGXI UNIV. - P.R.CHINA

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/29/2001
Publication Date: N/A
Citation: N/A

Interpretive Summary: Blackberry fruit contains high levels of antioxidant compounds. Antioxidant compounds have been reported to provide protection against harmful free radicals and to lower the incidence and mortality rates of cancer and heart diseases. However, little is known about the biochemical processes that occur during maturation and ripening of the blackberry. We initiated a program to examine whether free radical-induced oxidative stress and breakdown of membrane lipids were associated with fruit maturation, ripening and senescence. We found that ripening of blackberry was accompanied by a progression in oxidative/ peroxidative stress that resulted in increased saturation of polar lipids. It appears that a decline in free radical scavenging ability and the associated increase in oxidative stress may be requisite for mediating many of the physicochemical changes that facilitate maturation and ripening of blackberry fruit. This study is significant in understanding the mechanism of blackberry fruit ripening. Information provided in this work is useful for other scientists who are interested active in this field of research.

Technical Abstract: Maturation and ripening of blackberry fruit (Rubus sp.) was accompanied by decreased activities of oxygen scavenging enzymes [superoxide dismutase, glutathione-peroxidase, and catalase] and enzymes in the ascorbate-glutathione cycle [ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, and glutathione reductase]. Non-enzyme components in the ascorbate-glutathione cycle such as ascorbate (AsA), dehydroascorbate (DHAsA), glutathione (GSH) and oxidized glutathione (GSSG) and the ratios of AsA/DHAsA, GSH/GSSG were also decreased. These decreases were correlated with an increase in the ratios of saturated to unsaturated fatty acid of polar lipids and free sterols to phospholipids, thus contributing to decreased fluidity, enhanced lipid peroxidation, and membrane deterioration which may be associated with ripening and senescence in blackberry fruit.