Using an enzymatic galactose assay to detect lactose glycation extents of two proteins caseinate and soybean protein isolate via the Maillard reaction

Abstract

This proposed enzymatic assay could directly detect lactose glycation of the two proteins, and thus was more useful than the four chemical indices to monitor glycation of the two proteins. © 2016 Society of Chemical Industry.

In vitro immuno-modulatory ability of tryptic caseinate hydrolysate affected by prior caseinate glycation using the Maillard reaction or transglutaminase

“…Lactose-glycated caseinate was prepared via the Maillard reaction using the conditions as previously described (Wang & Zhao, 2017). In brief, the reaction system composed of caseinate (50 g/L) and lactose (80 g/L) at a pH value of 6.7, and was heated at a water bath (100°C) for 3 h with constant agitation.…”

“…GC-I hydrolysate was hydrolyzed by 2 mol/L trifluoroacetic acid at 100°C for 4 h as previously described (Račaitytė, Kiessig, & Kálmán, 2005), cooled to ambient temperature, neutralized into pH 7.0 using 2 mol/L NaOH, and then detected for galactose content as per the study (Wang & Zhao, 2017) using the galactose assay kit and procedure provided by the kit producer. Lactose content (g/kg protein) was thereby calculated chemically.…”

Lactose Glycation of the Maillard-Type Impairs the Benefits of Caseinate Digest to the Weaned Rats for Intestinal Morphology and Serum Biochemistry

“…To assay lactose content of the glycated digest, the sample was hydrolyzed by 2 mol/L trifluoroacetic acid at 100 °C for 4 h, cooled to 20 °C, and neutralized with 0.5 mol/L NaOH solution. The obtained hydrolysate was detected for galactose content and then calculated for lactose content (g/kg protein), as previously described [ 19 ].…”

“…Compared with the unglycated digests, whether the glycated digests have increased or decreased bioactivity to the body is absolutely important. Two previous studies by our group had found that the lactose-glycated caseinate digest had poor ability compared with the unglycated caseinate digest to promote barrier integrity of rat intestinal epithelial (IEC-6) cells or to combat against the camptothecin-induced apoptosis in IEC-6 cells [ 19 , 20 ]. Whether the lactose-glycated digest has a changed in vivo activity toward the weaned animals than the unglycated digest, for example, the vital body growth and intestinal development, is not investigated yet.…”

“…Such a study thus attracts our attention. To provide extra evidence for the conclusion from the two previous studies [ 19 , 20 ], this study also used the two digests in the animal experiment.…”