A molecular dynamic study of the starch obtained from the Mangifera indica Cv. Bourbon and Espada seeds by 13C solid state NMR

Solid State NMR

“…One example was showed in the literature, which exhibits the MAS and CPMAS solid state NMR spectra of seed flour bourbon mango spectra [15,16]. It shows that in these spectra have at least two segment areas of different molecular mobilities, and it may also a third due to the interaction of these two domains that may not be detected in this type of measurement.…”

“…In the low-field NMR, the relaxation parameters T 1 and T 2 for the hydrogen nuclei that constitute the samples can be measured directly, using the pulse sequences for such experiments and are widely used to characterize the types of molecular segments present in the samples and the interactions between them [15][16][17][18][19][20]. The time T 1 is associated with the return of the nucleus excited by the absorption of radiation to the equilibrium.…”

“…The T 1 H relaxation time é measured in the frequency of magnetic field generated by the external magnetic field. This relaxation must do with the return of the excited nuclei to its ground state after removal of the excitation frequency, and therefore, it allows to evaluate the molecular mobility of a material, global compatibility and homogeneity, as well as processes and plasticization [1][2][3][10][11][12][13][14][15]. In this process, the excess energy is emitted to the lattice in the form of dipole interaction since there is a lowering of the enthalpy of the nuclear spin system.…”

“…However, the inhomogeneity of the magnetic field causes the magnetization of the different nuclei processes at different rates when removing the RF and a time tau (τ) is needed to wait, which is chosen depending on the mobility of the sample; however, this inhomogeneity is refocused after an application of a 180° pulse, generating a single magnetization [1,15,16]. The pulse sequence normally used is Carr-PurcellMeiboom-Gill (CPMG), which contains a train of pulses [1][2][3][4][5].…”

13C‐NMR study of Dipteryx Alata Vogel starch

“…The focus of this work is to investigate the main chemical components and the molecular dynamic behavior of starch obtained from the seed of Dipteryx Alata Vogel , to use it, for example, in pharmacological drugs. The cumbaru starch was studied in bulk and was characterized by solid‐state nuclear magnetic resonance techniques; the analyses were carried out by using different solid‐state NMR techniques, such as magic‐angle spinning (MAS),5–8 cross‐polarization magic‐angle spinning (CPMAS),9–13 and the proton spin‐lattice relaxation time in the rotating frame (Tρ)5–13 determined by two experiments, variable contact time (VCT) and delayed contact time (DCT) experiments. In summary, the objective of this work was to evaluate the main polysaccharides presented in this starch and the molecular dynamic behavior in relation to the organization of dry starch granules obtained from Dipterxy Alata Vogel seed.…”