REU Student Project Abstract

Soil enzymes perform an essential function in organic matter decomposition by catalyzing hydrolysis of carbon compounds. Establishing soil sample storage and assay methods that preserve accuracy of measured enzyme activities is essential to further enzymatic soil research. Standardizing and optimizing soil enzyme assay methods can save industry, academia and government a significant amount of time and money allowing the effective completion of projects. This study is focused on determining the best storage treatment for soil to allow enzymatic activity to take place. Two storage treatments including air dry and refrigerated were used. These two storage treatments span from a cool temperature point to an average temperature range of humidity. The two enzymes evaluated were β-glucosidase (BG) and β-N-acetyl glucosaminidase (NAG) from a long-term crop rotation of corn-corn versus corn-soybeans. As temperature rises, the rate of enzyme reaction also increases. Changes in soil solution temperature as small as 1 or 2 degrees can introduce change in activity. However, when enzymes are denatured, they cannot regain activity. For both storage treatments, intervals of 5C per sample were evaluated ranging from 20C to 70C. The results showed there was a noticeable difference between the absorbance of the lower temperature points compared to the higher points with both enzymes.