两种测定苜蓿芽多糖方法的比较

采用蒽酮-硫酸法和苯酚-硫酸法测定了苜蓿芽多糖(MSP)含量,并比较了2种方法的适用性。结果表明:蒽酮-硫酸法和苯酚-硫酸法测定的MSP含量分别为(2.76±0.46)%和(3.17±0.88)%,前者显著低于后者(P<0.05);由于苜蓿芽提取液的颜色在苯酚-硫酸法测定波长下具有一定的吸光度,使其结果偏高,因此采用该方法需要对提取液进行脱色处理,而蒽酮-硫酸法测定结果更符合实际值。蒽酮-硫酸法和苯酚-硫酸法的回收率分别为(94.18±5.00)%和(99.40±3.51)%,回收率相对标准差分别为5.31%和3.53%,说明苯酚-硫酸法用于测定苜蓿芽多糖含量灵敏度更高、重复性更好。

Comparison of two methods in content determination of Medicago sativa polysaccharides

In this article,anthrone-sulfuric method and phenol-sulfuric method were used to test quantificationally Medicago sativa polysaccharides(MSP)content,and made sure which one is the better method.The results showed that the MSP content were(2.76±0.46)% and(3.17±0.88)%,respectively,the content using anthrone-sulfuric method was significantly lower than phenol-sulfuric method(P<0.05),recovery rate of two methods were(94.18±5.00)% and(99.40±3.51)% respectively,and the relative standard deviation of recovery rate were 5.31% and 3.53%,respectively.It means that the result of phenol-sulfuric method is on the higher side of actual value,because the color of alfalfa bud distilled solution absorbs the wavelength by the phenol-sulfuric method.So,the phenol-sulfuric method has better sensitivitvity and repeatability.