*3.4. Inhibition of Early (Amadori) Glycation Products*

Fructosamine is formed by covalent attachments of sugar molecule glucose to a primary amine, followed by isomerization. The molecule undergoes Amadori rearrangement and is an indicator of early glycation products. Thus, we aimed to understand the role of caffeic acid and coumaric acid in the inhibition of glycation. Figure 5A indicates the level of fructosamine in different samples.

**Figure 5.** *Cont*.

**Figure 5.** Estimation of antiglycation activity of caffeic and p-coumaric acid by monitoring (**A**) fructosamine content and protein oxidation by measuring (**B**) free thiol groups and (**C**) carbonyl content. **Figure 5.** Estimation of antiglycation activity of caffeic and p-coumaric acid by monitoring (**A**) fructosamine content and protein oxidation by measuring (**B**) free thiol groups and (**C**) carbonyl content.

In control HSA, the fructosamine level was nearly 22.12 nmol/mg protein. However, incubation of HSA with MG showed a hike in fructosamine content to 114.63 nmol/mg protein (Table 3). Fructosamine levels showed a decline with successive in-In control HSA, the fructosamine level was nearly 22.12 nmol/mg protein. However, incubation of HSA with MG showed a hike in fructosamine content to 114.63 nmol/mg protein (Table 3). Fructosamine levels showed a decline with successive increases in ligand concentration. In the presence of 200 µM caffeic acid, the fructosamine level declined to

46.13 nmol/mg, while coumaric acid declined the levels of fructosamine to 96.81 nmol/mg. The results showed that early end product formation viz fructosamine declines in the presence of both the ligands. Amadori product accumulations are associated with diabetic complications, and the selected natural polyphenols have the potential to reduce fructosamine content. The correlation shows the importance of caffeic acid and coumarin in managing complications due to diabetes.


**Table 3.** Effect of different concentrations of caffeic acid on alpha amylase.
