Used in biochemical research to measure phenylalanine ammonia-lyase (PAL) enzyme activity in plant tissues. The kit enables the detection and quantification of PAL, which plays a key role in the phenylpropanoid pathway involved in plant defense, lignin biosynthesis, and production of secondary metabolites. It is commonly applied in studies of plant stress responses, pathogen infection, and developmental physiology. The reagents allow for spectrophotometric or fluorometric analysis, providing a reliable method to assess enzyme kinetics and expression levels in various plant species under different experimental conditions.