Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Key Laboratory of Plant Functional Genomics of the Ministry of Education, Yangzhou University, Yangzhou 225009, China.
Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province/Joint International Research Laboratory of Agriculture & Agri-Product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China.
Molecules. 2018 Feb 15;23(2):427. doi: 10.3390/molecules23020427.
Chinese yam is an important edible starch plant and widely cultivated in China. Its rhizome and bulbil are starch storage tissues below and above ground, respectively. In this paper, starches were isolated from the rhizome and bulbil of Chinese yam, and their structural and functional properties were compared. Both starches had an oval shape with an eccentric hilum and a C-type crystalline structure. Their short-range ordered structure and lamellar structure had no significant difference. However, the rhizome starch had a significantly bigger granule size and lower amylose content than the bulbil starch. The swelling power and water solubility were significantly lower in the rhizome starch than in the bulbil starch. The onset and peak gelatinization temperatures were significantly higher in the rhizome starch than in the bulbil starch. The rhizome starch had a significantly higher breakdown viscosity and a lower setback viscosity than the bulbil starch. The thermal stability was lower in the rhizome starch than in the bulbil starch. The rhizome starch had a significantly lower resistance to hydrolysis and digestion than the bulbil starch. The above results provide important information for the utilization of rhizome and bulbil starches of Chinese yam.
山药是一种重要的食用淀粉植物，在中国广泛种植。其根茎和零余子分别是地下和地上的淀粉储存组织。本文从山药的根茎和零余子中分离出淀粉，并比较了它们的结构和功能特性。两种淀粉均呈椭圆形，偏心脐点，具有 C 型晶体结构。它们的短程有序结构和层状结构没有显著差异。然而，与零余子淀粉相比，根茎淀粉的颗粒尺寸更大，直链淀粉含量更低。与零余子淀粉相比，根茎淀粉的膨胀力和水溶性显著较低。起始和峰值糊化温度在根茎淀粉中显著高于零余子淀粉。与零余子淀粉相比，根茎淀粉的崩解粘度更高，回生粘度更低。与零余子淀粉相比，根茎淀粉的热稳定性较低。与零余子淀粉相比，根茎淀粉对水解和消化的抵抗力更低。以上结果为山药根茎和零余子淀粉的利用提供了重要信息。
