The effect of storage conditions on peroxidase activity

Soybean [Glycine max (L.) Merr] seed coats are an abundant and inex pensive source of peroxidase. Peroxidase's main function is to oxidize mole cules using hydrogen peroxide and elemental oxygen as a donor. Therefore, soybean peroxidase could be an economical alternative to current chemical oxidation techniques. Peroxidase enzyme activity declines after harvest, therefore reducing the extraction horizon or preventing the loss of enzyme activity during seed storage could generate significant cost savings. The objective of this research was to determine the effect of seed moisture con tent and temperature during storage on soybean seed coat peroxidase activ ity. Seed lots of high peroxidase cultivars were conditioned to differing seed moisture levels (9 and 13%) and stored in controlled temperature incubators (10, 20, 30, and 40 °C) or in a warehouse. Peroxidase activity was measured using the soybean seed coat peroxidase capture assay. Seed moisture did not affect the loss of peroxidase activity in stored soybean seeds but as storage temperatures increased from 10 to 40 °C the loss of peroxidase activity was accelerated.