Chinese Bulletin of Botany ›› 2012, Vol. 47 ›› Issue (3): 278-285.DOI: 10.3724/SP.J.1259.2012.00278

Previous Articles     Next Articles

Methods for Determining Relative Crystallinity of Plant Starch X-ray Powder Diffraction Spectra

Bin Xu1,2, Jianmin Man1, Cunxu Wei1*   

  1. 1Key Laboratories of Plant Functional Genomics of Ministry of Education and Crop Genetics and Physiology of Jiangsu Province, Yangzhou University, Yangzhou 225009, China;

    2Testing Center, Yangzhou University, Yangzhou 225009, China
  • Received:2011-09-13 Revised:2012-01-17 Online:2012-05-01 Published:2012-07-06
  • Contact: Cunxu Wei

Abstract: Plant starches have A-, B-, and C-type crystallinity. We investigated spectrum characteristics of starches from rice, potato, pea and lotus by X-ray powder diffraction (XRD). Peak-fitting, curved-line, straight-line mapping and curved-line mapping methods are commonly used for determining relative crystallinity of starch XRD spectra. The curved-line mapping method has reliable results. We found the relative crystallinity of rice starch negatively associated with amylose content and that of acid-modified lotus starches positively associated with acid hydrolysis degree by the curved-line mapping method. The crystallinity of lotus starch changed from C- to A-type during acid hydrolysis. These results would be useful for XRD analysis of crystallinity and relative crystallinity of plant starches.