脱乙酰基对天然魔芋葡甘聚糖分子形貌的影响

Effect of Deacetylate on the Structure Morphology of Natural Konjac Glucomannan

通过原子力显微镜直接观察魔芋葡甘聚糖(KGM)分子的三维结构形貌,KGM水溶液铺展在经Ca2+处理的云母片上,干燥固定后,可获得稳定、重复的图像。实验结果表明:稀溶液中KGM分子具有伸展的螺旋链状结构,单股的长度达200～400nm,厚度为1.0nm,宽度为35.0～35.2nm;脱乙酰后分子链卷曲成直径约40～50nm、厚3.5～5.0nm的弹性圆台状。

A method was developed to give topography of konjac glucomannan (KGM) by atomic force microscope (AFM). Aqueous solution of KGM is deposited as drops onto Ca2+ mica surface, air dried and fixed, and then it can obtain a steady and repeatable images. KGM has stretched spirality chain structure , single thigh length 200-400 nm , ply 1 nm and width 35.0-35.2 nm , and that konjac glucomannan change to flexible truncated cone after deacetylation, which diameter 40-50 nm and ply 3.5-5.0 nm .