Abstract: The purpose of the present study was to optimize the preparation of Juncao Ganoderma lucidum peptide-selenium chelate using response surface methodology. The independent variables were pH, the ratio of sodium selenite solution to protein hydrolysate (V/V), reaction time, and temperature. The response was selenium content. A quadratic polynomial regression model was established and its reliability was validated. The chelate was characterized by infrared (IR) spectroscopy. The results showed that in decreasing order significance, pH, reaction temperature, the ratio of sodium selenite solution to protein hydrolysate and reaction time affected the selenium content of chelates, and the optimal values of these factors were 9, 75 ℃, 1:2 and 60 min, respectively. The selenium content of the obtained product was (2 985.89±10.59) μg/g. IR spectral analysis confirmed the chelation reaction between Juncao Ganoderma lucidum peptides and selenium ions and the generation of a new chelate. This study can provide a new approach for the development and utilization of Juncao Ganoderma lucidum.

Key words: Juncao Ganoderma lucidum peptide, chelation, response surface methodology, peptide-selenium chelate