Hu Lanlan, Zheng Yi, Peng Yujiao, Yao Cheng, Zhang Huanxin
College of chemistry and molecular engineering, Nanjing Tech University, Nanjing 211816, China.
College of chemistry and molecular engineering, Nanjing Tech University, Nanjing 211816, China; Jiangsu Agri-animal Husbandry Vocational College, 8 Fenghuang East Road, Taizhou 225300, China.
Int J Biol Macromol. 2016 May;86:105-11. doi: 10.1016/j.ijbiomac.2016.01.045. Epub 2016 Jan 15.
A high-amylose starch was prepared from ginkgo by hydrolysis using isoamylase and its structures (morphology and crystallinity) and physicochemical properties (swelling factor, water solubility and gelatinization) were determined. The experiments used response surface methodology to determine the optimum parameters for enzymatic hydrolysis: pH 5.0 at 52 °C for 170 min, using an enzyme dose greater than 100 IU/ml. The experimentally observed maximum yield of ginkgo amylose under these conditions was 74.74% and the blue value was 0.756. The high-amylose ginkgo starch showed an irregular surface and porous inner structure while the native starch granules were oval with a smooth surface. X-ray showed that the high-amylose starch displayed a V-type structure. Because of its high amylose content and different structural characteristics, high-amylose starch exhibited a higher gelatinization peak temperature (109.25 °C) and water solubility, and a lower crystallinity (19.13%), gelatinization enthalpy (63.83 J/g), and swelling power. The present study has indicated that high-amylose starch prepared using isoamylase has unique functional properties, which lays the foundation for the wider application of ginkgo starch.
采用异淀粉酶水解法从银杏中制备了高直链淀粉，并对其结构（形态和结晶度）和理化性质（膨胀因子、水溶性和糊化性质）进行了测定。实验采用响应面法确定酶解的最佳参数：52℃、pH 5.0条件下反应170分钟，酶用量大于100 IU/ml。在此条件下，实验观察到银杏直链淀粉的最大产率为74.74%，蓝色值为0.756。高直链银杏淀粉表面不规则，内部结构多孔，而天然淀粉颗粒呈椭圆形，表面光滑。X射线显示高直链淀粉呈现V型结构。由于其高直链淀粉含量和不同的结构特征，高直链淀粉表现出较高的糊化峰值温度（109.25℃）和水溶性，以及较低的结晶度（19.13%）、糊化焓（63.83 J/g）和膨胀力。本研究表明，采用异淀粉酶制备的高直链淀粉具有独特的功能特性，为银杏淀粉的更广泛应用奠定了基础。
