Asparaginase

BeschreibungUsing the enzyme asparaginase (L-asparagine amidohydrolase, EC 3.5.1.1), it is possible to significantly reduce the formation of the cooking carcinogen acrylamide during roasting, deep-frying, or baking of foods. The enzyme hydrolyzes free asparagine to aspartic acid, thereby preventing the formation of acrylamide by reaction of asparagine with reducing sugars at elevated temperatures during the Maillard reaction. The mitigation of acrylamide formation is especially important for a number of cereal- and potato-based products, including crackers, crispbread, gingerbread, biscuits, French fries, and potato chips. After asparaginase pretreatment, the acrylamide concentration of certain foods could be reduced by up to 97 % [84, 86]. By means of in vitro directed evolution, the properties of asparaginase were optimized. For example, an Asp133Leu mutation of a wild-type enzyme showed a significantly improved thermal stability. The enzyme’s half-life at 50 C increased from 3 to 160 h, and the half-inactivation temperature of the mutant was 9 C higher.

VerwendenAsparaginase from Escherichia coli has been used: to compare the cytotoxic effect of L-asparaginase purified fromStreptomyces brollosaeNEAE-115as a standard in asparaginase assay to quantify asparaginase activities in various eel tissuesto elicit amino acid deprivation