Atomic Force Microscopy Investigation of Disorder Process on Rice Starch Granule Surface

Starch - Starke (Impact Factor: 1.68). 09/2006; 58(9):475–479. DOI: 10.1002/star.200500471


Precise ultra-structures of rice starch granules have been analyzed by atomic force microscopy combined with a structure-disorder process at ambient conditions. Atomic force microscopy is a useful technique to obtain images under atmospheric condition with a nanometer-scale resolution. The images obtained by a high-resolution tapping mode revealed a detailed surface ultra-structure of native rice starch granule with a diameter of approximately 100 nm. The ultra-structures were arranged in series like a chain, and the chain was bundled together into a rod or larger column. After a disorder process using plasticizing/lyophilization of the granules, a significant change in the organization of the surface morphology was detected. Some fine particles of approximately 30 nm in diameter were observed, which might correspond to the individual single cluster in the crystalline region of the starch granule.

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Available from: Ali Ayoub, Jun 14, 2015
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    • "On the opposite limit of size scale, namely the sub-granule details , neither optical microscopy nor SEM can provide enough contrast to resolve features (BeMiller and Whistler, 2009; Singh et al., 2003; Cornuéjols and Pérez, 2010; Szymon´ska et al., 2009; Seetharaman and Bertoft, 2012). However, in recent years AFM has appeared as the most promising technique for resolving granule substructures (Juszczak et al., 2003; Ohtani et al., 2000; An et al., 2008; Baldwin et al., 1997, 1998; Park et al., 2011; Ridout et al., 2002, 2003; Szymon´ska and Krok, 2003; Tang and Copeland 2007; Ayoub et al., 2006; Sujka and Jerzy, 2009). For example, in Fig. 2 some similar features appear. "
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    • "In contrast, atomic force microscopy (AFM) enables high-resolution (< 1 nm) 3D imaging of biological surfaces in atmospheric and even aqueous conditions and does not require the samples to be metal coated (Gallant et al. 1997, Ohtani et al. 2000). The exterior (Gallant et al. 1997) and interior surfaces (Baker et al. 2001, Juszczak 2003) of starch granules from various food crops have been investigated (Baldwin et al. 1998, Ohtani et al. 2000, Ridout et al. 2002, Kim et al. 2005, Ayoub et al. 2006, Dang et al. 2006), but there have been few studies on starch granules in conifer needles. Although TEM has been used to examine the histochemistry (Lepedus et al. 2005) and stress responses of plants (Utriainen et al. 2000, Kivimäenpää et al. 2001), these studies were made on cross sections of needle segments, a time consuming and impractical procedure for assessing large numbers of samples. "
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    Tree Physiology 10/2008; 28(10):1593-9. DOI:10.1093/treephys/28.10.1593 · 3.66 Impact Factor
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