Abstract:

Objective: The ultrasonic-assisted extraction process for polysaccharides from the residue of Allium mongolicum Regel seeds after the oil of extraction with supercritical carbon dioxide was optimized using response surface methodology. Methods: On the basis of single factor experiments, a three-factor, three-level Box-Behnken central composite design (CCD) was utilized for mathematical modeling for polysaccharide yield as a response to extraction temperature and time as well as material/water ratio, followed by response surface analysis of the relationship between the function and the three variables. Results: The optimum conditions for the extraction of Allium mongolicum Regel seed polysaccharides were as follows: water/ material ratio, 48.0:1; ultrasonic power, 300 W; extraction temperature, 73.1 ℃; extraction time, 1.6 h; and extraction number, 2. Under such conditions, the model-predicted and experimental values of polysaccharide yield were 7.59% and 7.47%, respectively, revealing 1.58% relative error between them. Conclusion: Ultrasonic treatment can substantially shorten the time required for polysaccharide extraction, and the developed extraction process is simple, reliable and highly efficient.

Key words: response surface methodology, Allium mongolicum Regel seeds, polysaccharides, ultrasonic-assisted extraction