Functional properties of guava seed glutelins.
Five guava seed glutelin extracts were obtained with different buffer solutions: Na(2)B(4)O(7) alone (Glut.Bo) or containing SDS (Glut. BoSDS), 2-mercaptoethanol (Glut.Bo2-ME), or a combination of both (Glut. BoSDS2-ME) and NaOH (Glut.Na). All borate buffer solutions were at pH 10. The higher yield of glutelins corresponded to the Glut. BoSDS extract (81.9% dry basis) and the lower to Glut.Bo (6.8%). The functional properties of the five guava seed glutelin extracts were determined. Glut. BoSDS, Glut. BoSDS2-ME, and Glut.Na showed high values for several properties, including surface hydrophobicity (7.7, 10.8, and 0.6, respectively), solubility at pH 10 (91.1, 77.9, and 96.7, respectively), water-holding capacity at pH 3.6 (1.7, 2.5, and 2.8, respectively), emulsifying activity index (pH 10; 503.5, 238.2, and 838.0, respectively), and foaming properties (pH 10; V(0) = 0.14, 0.25, and 0.19, respectively; V(max) = 6.1, 5.59, and 4.51, respectively; t(1/2) = 266, 255.3, and 94 s, respectively). These results suggest that the denaturing reagent (SDS or NaOH) during extraction conferred on the proteins a structure that facilitated the development of their functional properties.
Bernardino-Nicanor
Aurea
A
Departamento de Graduados e Investigación en Alimentos de la Escuela Nacional de Ciencias Biológicas (IPN), Prolongación de Carpio y Plan de Ayala, 11340 México 17, DF, Mexico.
Añón
M Cristina
MC
Scilingo
Adriana A
AA
Dávila-Ortíz
Gloria
G
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D045703:Emulsifying Agents / Q000737:chemistry; D005983:Glutens / Q000737:chemistry* / Q000302:isolation & purification; D057927:Hydrophobic and Hydrophilic Interactions; D031647:Psidium; D012639:Seeds / Q000737:chemistry*; D012995:Solubility; D014867:Water / Q000032:analysis
D045703:Emulsifying Agents; D014867:Water; D005983:Glutens