|Hodges, D - AGRI-FOOD CANADA|
|Munro, Kathleen - AGRI-FOOD CANADA|
|Toivonen, Peter - PACIFIC AGRI-FOOD|
Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 2, 2004
Publication Date: August 4, 2004
Citation: Hodges, D.M., Lester, G.E., Munro, K.D., Toivonen, P.M. 2004. Oxidative stress: Importance for postharvest quality. Hortscience. 39(5):924-929. Interpretive Summary: Oxidative stress results from an organism's inability to cope with high levels of AOS. Many exogenous factors such as preharvest production practices, field stresses, harvesting techniques, commodity maturity, storage conditions, processing protocols, and transport and marketing procedures can interact with endogenous factors such as genotype, genetic up- or down-regulation, hormones, and/or general senescent/ripening processes to influence AOS levels, scavenging capacity, and ultimately postharvest oxidative stress of fruits and vegetables. With so many variables, it is often difficult to document or predict effects of exogenous and/or endogenous factors on postharvest oxidative stress. However, the response of antioxidative systems to increasing oxidative stress during postharvest storage of fruits and vegetables does not appear to be consistent between species or cultivars/varieties within a species, underlying the complexity of antioxidant responses to oxidative stress. Nonetheless, a survey of recent research does suggest that the H2O2 and ascorbate metabolism are intrinsically associated with oxidative stress in postharvest storage situations. Further understanding of the sequence of events in oxidative injury may lead to an improved ability to predict the development of postharvest oxidative stress.
Technical Abstract: Oxidative stress, whereby the production of active oxygen species (AOS) such as superoxide (O2), hydrogen peroxide (H2O2), and the hydroxyl radical ('OH) exceeds the capacity of the organism to scavenge them, has been associated with postharvest quality losses of fruits and vegetables. Symptoms of oxidative stress can include storage disorders such as superficial scald and core browning, induced senescence, colour loss, lipid peroxidation, and loss of membrane integrity. Many exogenous factors such as preharvest production practices, field stresses, harvesting techniques, commodity maturity, storage conditions, processing protocols, and transport and marketing procedures can influence AOS levels, scavenging capacity, and ultimately postharvest oxidative stress of fruits and vegetables. More than one of these factors can occur simultaneously or consecutively to exacerbate oxidative damage. Increased awareness of the factors which play a role in inducing and/or exacerbating oxidative stress will limit postharvest quality losses/disorder related to oxidative injury.