Microplate assay for soybean seed coat peroxidase activity

Soybean seed coats are a readily available source of peroxidase. Because of the oxidative nature of peroxidase, there are several areas where it could replace current chemical oxidation techniques. The objective of this research was to develop a non-destructive, quantitative peroxidase assay for efficient identification of high-peroxidase soybean [Glycine max (L.) Merr] genotypes. An enzyme-capture assay was developed, which allowed both sensitive and reliable quantitation of peroxidase activity. The technique showed a linear response to solutions of known peroxidase activity and could distinguish between high and low peroxidase cultivars as measured by guaiacol. This technique identified differences in peroxidase activity between genotypes within a segregating population and would aid in the efficient selection and identification of high-peroxidase cultivars, which could provide a large, renewable source of peroxidase.