Phenylalanine response in rice kernel under chitosan nanoparticles spraying

Since phenylketonuria patients have a metabolic defect, should use specific foods that have low phenylalanine levels. These foods are usually produced by hydrolysis processes. The most important problems of the foods are unpleasant to taste and expensive. The main objective of this study was to investigate the possibility of reducing the amount of phenylalanine in rice kernel under spraying of chitosan nanoparticles. Treatments were different concentrations of chitosan nanoparticles spraying (0, 500, 1000, 1500 µl L−1). The treatments effects were studied in a randomized complete block design with four replications. Experimental variables were phenylalanine, phenylalanine ammonia-lyase activity and total grain protein. The results showed that the total protein and phenylalanine level in rice kernel decreased under all concentrations of chitosan nanoparticles compared to the control, while the activity of phenylalanine ammonia-lyase was higher than that of the control. In this experiment, 1000 µl L−1 of chitosan nanoparticles was found as the optimum concentration, since minimum phenylalanine level and maximum phenylalanine ammonia-lyase activity were affected by this concentration. Therefore, chitosan nanoparticles spraying during the grain growth was able to reduce phenylalanine level in rice kernel.