Using enzymes for the analysis of foods and other biological samples

( L. Martínková, B. Křístková, R. Příhodová, M. Kotík, L. Rucká, V. Křen, P. Bojarová)

Enzymes are valuable tools for analyzing foods and other biological samples because they are selective, sensitive, and operate under mild conditions. Their reaction products can often be measured photometrically, allowing assays to be performed with simple photometric devices rather than sophisticated instruments such as HPLC or LC-MS. This makes enzymatic assays cost-effective and suitable for high-throughput analysis. Enzymes dependent on NAD or NADP cofactors are especially important, as the reduced cofactors can be easily detected by photometric methods, and form the basis of many commercial assay kits.

Our aim has been to develop new or improved enzymatic assays for detecting toxic or undesirable compounds in foods, plants, and waste materials. Examples (Fig. 1) include assays for cyanide, 3-cyanoalanine, and L-asparagine. The enzymes used in these assays were produced in our laboratory by expressing the relevant genes in Escherichia coli.

Figure 1: Using enzymes to determine hydrogen cyanide (released from natural cyanogenic glucosides in plants), 3-cyanoalanine (a toxic amino acid found in some animal fodder) or L-asparagine (converted into toxic acrylamide during thermal food processing).

Literature

*Martínková L, Příhodová R, Rucká L, Kotik M, Křístková B, Bojarová P, Křen V. (2026) Colorimetric determination of the plant toxin ß-cyano-L-alanine using a multistep enzyme reaction. Talanta 300, Article 129159. https://doi.org/10.1016/j.talanta.2025.129159

*Martínková L, Kulik N, Rucká L, Kotik M, Křístková B, Šťastná K, Novotný P, Příhodová R, Bojarová P, Křen V (2024) Biotransformation of free cyanide to formic acid by a cyanide hydratase-formamidase cascade reaction. Process Biochemistry 142:62-67. https://doi.org/10.1016/j.procbio.2024.04.009

*Šťastná K, Martínková L, Rucká L, Křístková B, Příhodová R, Bojarová P, Pátek M (2025) Design and development of spectrophotometric enzymatic cyanide assays. Analytical and Bioanalytical Chemistry 417, 697–704. https://doi.org/10.1007/s00216-024-05703-0