Effects of Lactiplantibacillus plantarum fermentation on hydrolysis and immunoreactivity of Siberian apricot (Prunus sibirica L.) kernel

Siberian apricot (Prunus sibirica L.) kernels have a variety of medicinal effects and can be used in the production of Siberian apricot kernel drinks or other foods, such as marzipan or biscuits, but their potential immunoreactivity cannot be ignored. In this research, the hydrolysis effect of several fermented strains on Siberian apricot kernel protein (SAKP) was measured by the degree of hydrolysis, and the content of free amino acids and Lactiplantibacillus plantarum was finally selected to ferment SAKP to reduce its immunoreactivity. SDS‒PAGE and HPLC were used to determine the molecular weight of SAKP and to confirm that the macromolecule was hydrolyzed into small molecules. The fermentation effect was measured by the change in pH and small peptide content in the fermentation process. The optimal fermentation conditions were determined by a single-factor experiment as follows: apricot kernel powder:water = 1:20 (w/v), inoculation amount of 0.1% (v/w), initial pH of 6.5 for 36 h of fermentation. Atomic force microscopy (AFM) was used to observe the changes in SAKP particle structure after fermentation, and indirect ELISA was used to determine that the immunoreactivity decreased to 29.64% ± 1.03% after fermentation, which indicated that fermentation reduced the immunoreactivity of SAKP.