提取方法对香菇多糖性质的影响

Effects of Extraction Methods on Lentinan Properties

采用回流热水提取法、超声提取法、微波提取法、高温热水提取法提取香菇多糖,通过香菇多糖抗氧化活性、分子形态、单糖组成等指标对提取方法进行评价.结果表明:在相同的提取时间内,高温热水提取所得香菇多糖的提取率最高,达14.25%;高温热水提取的多糖相对分子质量最小;不同提取方法提取的多糖溶液的黏度均随浓度的增大而增大,在相同浓度下多糖溶液的表观黏度大小依次为回流热水提取>微波提取>超声提取>高温热水提取;高温热水提取的多糖分子高度最低、平均粗糙度最小;不同的提取方法会对多糖的聚集度和支链结构产生一定的影响,并因此影响其抗氧化活性,4种方法提取的多糖抗氧化活性大小依次为:超声提取>微波提取>回流热水提取>高温热水提取;不同提取方法提取的多糖的单糖组成均以甘露糖、葡萄糖和半乳糖为主.

Lentinan was extracted from Lentinus edodes through hot water reflux,high temperature-hot water,ultrasonic 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 extraction 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 apparent viscosities of the four polysaccharide solutions obtained respectively through the above four extraction methods 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 roughness; （5） different extraction methods all affect the aggregation and branches of polysaccharides to a certain degree,thus making the corresponding antioxidant activities in the order of ultrasonic ＞ microwave ＞ hot water reflux ＞ high temperature-hot water; and （6） the polysaccharides obtained through different extraction methods are mainly composed of mannose,glucose and galactose.