Abstract:

Lentinan was extracted from Lentinus edodes through hot water reflux,high temperature-hot water,ultra-sonic and microwave.Then,these extraction methods were evaluated according to the antioxidant activity,molecular shape and monosaccharide composition of the products.The results show that (1) within the same amount of extrac-tion time,the high temperature-hot water method achieves the maximum lentinan yield rate (14.25%) ; (2) the polysaccharides obtained through high temperature-hot water are of the lowest relative molecular mass; (3) the ap-parent viscosities of the four polysaccharide solutions obtained respectively through the above four extraction me-thods all increase with the increase of the polysaccharide concentration,and they are in the order of hot water reflux ＞microwave ＞ ultrasonic ＞ high temperature-hot water at the same concentration; (4) the high temperature-hot water extraction brings about the polysaccharides with the smallest molecule height and the lowest average rough-ness;(5) different extraction methods all affect the aggregation and branches of polysaccharides to a certain de-gree,thus making the corresponding antioxidant activities in the order of ultrasonic ＞ microwave ＞ hot water re-flux＞ high temperature-hot water; and (6) the polysaccharides obtained through different extraction methods are mainly composed of mannose,glucose and galactose.

Key words: lentinan, hot water reflux extraction, ultrasonic extraction, microwave extraction, high temperature-hot water extraction, antioxidant activity, molecular shape, monosaccharide composition