灰树花β-葡聚糖的高效凝胶渗透色谱行为

Behaviors of β-Glucan from Grifola frondosa in High Performance Gel Permeation Chromatography

以4种不同蛋白质含量的灰树花β-1，3／1，6-葡聚糖（GF1，GF2，GF3，GF4）和1种α-1，4／1，6-葡聚糖（P100）为研究对象，探讨了它们在不同盐浓度和不同pH下的高效凝胶渗透色谱（HPGPC）行为。结果表明：灰树花口．葡聚糖相对分子质量在低于0．025mol／L的氯化钠溶液中急剧降低，在0．1—0．2mol／L的氯化钠溶液中趋于平稳。在pH3—6时，其相对分子质量随pH增加而急剧增加；在pH6—9范围内变化较小；pH高于9后又稍微增加。在相同条件下，α-1，4／1，6-葡聚糖的相对分子质量不受盐浓度和pH值变化的影响。灰树花β-葡聚糖在水溶液中可形成超螺旋结构，该结构受溶液盐浓度和pH值变化的影响，导致分子聚集状态不同，从而呈现不同的凝胶渗透色谱行为，表现为相对分子质量升高或降低。

The high performance gel permeation chromatographic （HPGPC） behaviors of four β-1,3/1,5-glucans （GF1, GF2, GF3, GF4） with different protein contents and one a-1,4/1,5- glucan （P100） from Grifola frondosa were examined with different concentrations of NaCl solution and pH values. The experimental results showed that the relative molecular mass （Mr） of the β-glucans sharply dropped as the NaCl concentration was less than 0. 025 mol/L and then tended to be stable as the NaCl concentration was raised from 0. 1 to 0.2 mol/L, the Mr increased quickly from pH to 5, and then maintained stable from pH 5 to 9, but slightly increased as the pH value was higher than 9. However, the Mr of the α-1,4/1,5-glucan was slightly affected by either different concentrations of NaCl or different pH values. The β-glucan existed in a super-helix structure in aqueous solution, which could be influenced by the NaCl concentration and pH value. These factors led to the different molecular aggregation states, and the increase or decrease of the Mr of β-glucans, displaying a variety of HPGPC behaviors.