Glycation promoted by dynamic high pressure microfluidisation pretreatment revealed by high resolution mass spectrometry.

The effect of dynamic high pressure microfluidisation (DHPM) pretreatment on the glycation of bovine serum albumin (BSA) was investigated. A detailed glycation map was obtained from high resolution mass spectrometry. Without DHPM pretreatment, only 7 glycation sites were identified, whereas the numbers were increased to 10, 11 and 11 when BSA-glucose was pretreated with DHPM at 50, 100 and 200 MPa, respectively, suggesting that DHPM pretreatment can significantly promote the Maillard reaction. Average degree of substitution per peptide molecule BSA (DSP) was used to further evaluate the glycation level under various DHPM conditions. All the DHPM pretreated samples exhibited elevated glycation level compared to the un-pretreated sample. With 100 MPa DHPM pretreatment, the protein showed the most significantly enhanced glycation extent. In addition, our results suggest that Maillard-type glycation followed by mass spectrometry analysis can be used to study the conformational changes when proteins are disturbed by external forces.