Abstract:

Ginseng roots were defatted by supercritical fluid extraction, treated to remove ginsenosides and extracted by a
supercritical fluid assisted hot water extraction method to obtain ginseng polysaccharides. The optimal conditions for the
extraction of ginseng polysaccharides were determined by orthogonal array experiments. The results showed that when
the extraction process was conducted on samples pulverized to a particle size of 0.20 mm at 80 ℃ and 30 MPa for 1.5 h
with a raw material to entrainer of 1:2.5 (g/mL), the yield and purity of ginseng polysaccharides were (38.03 ± 1.43)% and
(54.71 ± 2.16)%, respectively, increased by 16.15% and 13.44% compared to those obtained with the traditional hot water
extraction method, respectively. Monosaccharide composition and mean molecular mass of ginseng polysaccharides were
analyzed by high performance liquid chromatography (HPLC) and high performance gel permeation chromatography (HPGPC).
The results showed that there were a large quantity of glucose and small quantities of galactose and arabinose. The contents of the
three monosaccharides obtained with supercritical fluid assisted hot water extraction were significantly higher than those obtained
with hot water extraction. The average molecular mass of ginseng polysaccharides extracted by supercritical fluid assisted hot
water extraction and hot water extraction were 123 847 and 127 016 u, respectively. More polysaccharide species in ginseng roots
were extracted by supercritical fluid assisted hot water extraction than by hot water extraction.

Key words: supercritical fluid assisted hot water extraction, ginseng polysaccharides, compositional analysis