Proteins as nano-carriers for bioactive compounds. The case of 7S and 11S soy globulins and folic acid complexation

EMILIA OCHNIO; JIMENA H MARTÍNEZ; MARIANA C ALLIEVI; MARCOS PALAVECINO; MARTÍNEZ KARINA D.; OSCAR E. PÉREZ

Polymers

MDPI AG, St. Alban-Anlage 66, 4052 Basel, Switzerland

Lugar: Switzerland; Año: 2018

2073-4360

Isolated7S and 11S globulins obtained from defeated soy flour were complexated withfolic acid (FA) in order to generate nano-carriers for this important vitaminin human nutrition. Fluorescence spectroscopy and dynamic light scattering wereapplied to follow the nano-complexes formation and for their characterization.Fluorescence experimental data were modeled by the Stern-Volmer and a modifieddouble logarithm approaches. The results obtained confirmed staticquenching. The number of binding sites on the protein molecule was ~1. Thevalues obtained for the binding constants suggest a high affinity betweenproteins and FA.Particle size distribution allowed to studythe proteinaggregation phenomenon induced by FA bound to the native proteins. Z-averagemanifested a clear trend to protein aggregation. 11S-FA nano-complexes resultedthe more polydisperse. ζ-potential of FA nano-complexes did not show aremarkable change after FA complexation.Thebiological activity of nano-complexes loaded with FA was explored in terms oftheir capacity to enhance the biomass formation of Lactobacillus caseiBL23. The results concerning to nano-complexesinclusion in culture media showed higher bacterial growth. Such a result wasattributed to the entry of the acid by the specific receptors concomitantly bythe peptide receptors. These findings have technological impact for the use ofglobulins-FA based nano-complexes in nutraceutical, pharmaceutical and foodindustries.