Comparative study on the effects of nystose and fructofuranosyl nystose in the glycation reaction on the antigenicity and conformation of β-lactoglobulin. (1st December 2015)

• Record Type: Journal Article
• Authors: Zhong, Junzhen; Tu, Yue; Liu, Wei; Luo, Shunjing; Liu, Chengmei
• Is Part Of: Food chemistry. Volume 188(2015)
• Page Start: 658
• Page End: 663
• Publication Date: 2015-12-01
• Subjects: β-Lactoglobulin -- Conjugation -- Antigenicity -- Conformation; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2015.05.015
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: β-LG were conjugated with GF3 and GF4, respectively. There was no significant different antigenicity between the two conjugations. Conformation of β-LG after conjugated with GF3 and GF4 changed differently. Different conformation changes may be also resulted in similar antigenicity. Abstract: Our previous work indicated that the antigenicity of bovine β-lactoglobulin (β-LG) decreased after conjugation with fructo-oligosaccharides (FOS) which was related to its conformational changes. In attempt to unravel further changes of β-LG antigenicity, nystose (GF3 ) and 1 F -β-fructofuranosyl nystose (GF4 ) of FOS were used to investigate the relationship between conformation and antigenicity. The antigenicity of β-LG after conjugated with GF3 and GF4 decreased from 143.4 to 29.5 and 31.6 μg/mL, respectively. The results of mass spectrometry revealed that the molecular weight of β-LG increased from 18.4 to 19.8 and 19.1 kDa after conjugation with GF3 and GF4, respectively. It was shown that the conformational changes of β-LG after conjugation with GF3 were bigger than that with GF4, including quenching of fluorescence intensity, the red-shift of fluorescence spectra, and the increase in sulfhydryl content. However, there was no significant difference in the antigenicity between β-LG-GF3 and β-LG-GF4 conjugates ( P > 0.05).