摘要
Platycodon grandiflorum polysaccharides(PGPs)are naturally occurring compounds derived from the flowers of platycodon grandiflorum.the microwave assisted extraction(MAE)of PGPs was studied.A three-level and three-factor Box-Behnken design was used to optimize MAE conditions,and the effects of operating conditions including microwave power(180-540 W),extraction time(20-60 s)and liquid to solid ratio(20-30 v/w)on the extraction yield of PGPs were studied through response surface methodology(RSM).The results showed that the highest yield of PGPs reached 8.35 g/(100 g)at 360 W microwave power,40 s extraction time and 25.2 v/w liquid to solid ratio.The extraction yield of PGPs was significantly affected by liquid to solid ratio(P<0.01),microwave power and extraction time(P<0.05).Compared with the conventional solvent extraction,MAE is more efficient and rapid due to the disruption of the flower tissue microstructure as a result of microwave acoustic cavitation as observed with the scanning electron microscopy(SEM).A macroporous resin,HPD400,was found to be effective for purifying the PGPs extract.
基金
Thanks Shandong University of Technology(2004KJM09)and the Subject of Domestic Visiting Scholar for outstanding teachers to support this work。
