University of Kentucky
Harnessing Enzymes to Improve Industrial Starch Processing
Institution
University of Kentucky
Faculty Advisor/ Mentor
Matthew Gentry
Abstract
Starch is a vital energy molecule in plants and a key component of the human diet. It also has a wide variety of uses in industry, such as a feedstock for producing paper, textiles, adhesives, plastics, pharmaceuticals, and biomaterials for biofuel production. However, starch is difficult to manipulate during industrial processing because it is water-insoluble. To overcome this recalcitrant nature, industrial processers treat starch by milling and then heating and harsh chemicals, a process that is costly and environmentally unfriendly. Obviously, plants do not break down starch in this manner. In plants, starch is degraded in a cyclical nature that involves three main classes of enzymes: dikinases, amylases, and phosphatases. If the cyclic nature of plant degradation of starch can be applied to industrial manufacturing, then the cost to degrade starch would go down significantly and the use of harsh chemicals would not be needed. Our work has focused on testing this hypothesis. We set out to establish a functional assay to assess how efficiently these enzymes bind sugars. Before my work the Gentry lab, I performed laborious binding assays to measure the binding of the dikinases and phosphatases to starch. This assay only qualitatively assessed binding, but did not quantitatively measure binding. We established a protocol to quickly, reproducibly, and quantitatively measure the binding of the enzymes to starch. We found that the starch dikinases and phosphatases possess differing abilities to bind starch substrates. Additionally, we performed starch degradation assay to measure glucose release after treatment with a combination of different enzymes. The results of the degradation assay show that enzymes increased starch degradation.
Harnessing Enzymes to Improve Industrial Starch Processing
Starch is a vital energy molecule in plants and a key component of the human diet. It also has a wide variety of uses in industry, such as a feedstock for producing paper, textiles, adhesives, plastics, pharmaceuticals, and biomaterials for biofuel production. However, starch is difficult to manipulate during industrial processing because it is water-insoluble. To overcome this recalcitrant nature, industrial processers treat starch by milling and then heating and harsh chemicals, a process that is costly and environmentally unfriendly. Obviously, plants do not break down starch in this manner. In plants, starch is degraded in a cyclical nature that involves three main classes of enzymes: dikinases, amylases, and phosphatases. If the cyclic nature of plant degradation of starch can be applied to industrial manufacturing, then the cost to degrade starch would go down significantly and the use of harsh chemicals would not be needed. Our work has focused on testing this hypothesis. We set out to establish a functional assay to assess how efficiently these enzymes bind sugars. Before my work the Gentry lab, I performed laborious binding assays to measure the binding of the dikinases and phosphatases to starch. This assay only qualitatively assessed binding, but did not quantitatively measure binding. We established a protocol to quickly, reproducibly, and quantitatively measure the binding of the enzymes to starch. We found that the starch dikinases and phosphatases possess differing abilities to bind starch substrates. Additionally, we performed starch degradation assay to measure glucose release after treatment with a combination of different enzymes. The results of the degradation assay show that enzymes increased starch degradation.