13C ss-NMR Singular value decomposition and fitting for sorghum proteins conformation elucidation.

• Autor(a) principal: RIBEIRO, T. S.
• Data de Publicação: 2022
• Outros Autores: SCRAMIN, J. A., RODRIGUES, J. A. S., BERNARDES FILHO, R., COLNAGO, L. A., FORATO, L. A.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice)
• Texto Completo: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1143402
• topic: Kafirin; Secondary structures proteins; 13C NMR spectroscopy

Kafirins, water-insoluble proteins from Sweet Sorghum BR501 grains, have been an alternative to prepare edible coatings for food due to their hydrophobic character. In this work, the secondary structures (SS) content of reduced (SSr) and unreduced (SSu) kafirins were determined by 13C solid-state-NMR spectroscopy using areas of carbonyl peak. The SS elucidate by fitting the signal with the Lorentzian function shows 56% and 59% of α-helix and 40% and 12% of β-sheet structures for SSr and SSu, respectively. The SS also were elucidated by a Singular value decomposition- SVD method shows 55% and 49% of α-helix and 12% and 8% of β-sheet structure for SSr and SSu, respectively. Since SVD does not depend on the operator and has higher correlation coefficients for α-helix (0.96%) and β-sheet (0.91%), it is a reliable method to quantify the SS of insoluble proteins using the 13C NMR signal.