2.3.3. Inhibition in Protein Aggregate Formation

cance was defined as \* *p* < 0.05, \*\* *p* < 0.01, \*\*\* *p* < 0.001.

2.3.3. Inhibition in Protein Aggregate Formation Glycation causes the binding of carbonyl groups to proteins, resulting in the creation of protein molecules clustering, which is also known as protein aggregation. As a result of glycation, protein aggregates formation occurs. In one of our previous studies, we showed aggregation occurs due to protein glycation [1]. Garlic extract had a beneficial effect on the inhibition of protein aggregation. The addition of extract lowered the aggregation index of G-HSA in a concentration-dependent manner (Figure 5). At a concentra-Glycation causes the binding of carbonyl groups to proteins, resulting in the creation of protein molecules clustering, which is also known as protein aggregation. As a result of glycation, protein aggregates formation occurs. In one of our previous studies, we showed aggregation occurs due to protein glycation [1]. Garlic extract had a beneficial effect on the inhibition of protein aggregation. The addition of extract lowered the aggregation index of G-HSA in a concentration-dependent manner (Figure 5). At a concentration of 100 µg/mL, the extract exhibited the levels of aggregation (67.77%).

### tion of 100 µg/mL, the extract exhibited the levels of aggregation (67.77%). 2.3.4. Amyloid Structure Inhibition

Congo red (CR) dye is used to determine how much of a protein's secondary structure has been altered. CR contacts hydrophobic clefts located in between beta fibrils and has a unique ability to bind to the protein sheet structure. After binding, the CR dye has a specific absorbance of 530 nm. In Figure 6, the findings of the CR binding experiment showed reduction in cross amyloid structure formation (33.26%) compared with positive controls (G-HSA). By masking the sites of glycation and limiting the surface area accessible by solvent, garlic extract reduced HSA fibrillation and perhaps prevented the transition from α-helix to β-sheet.

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**Figure 5.** Percentage aggregation vs. concentration of garlic extract. Native HSA and G-HSA were incubated for 10 weeks and served as negative and positive controls, respectively. G-HSA was incubated with various concentrations (0–100 µg/mL) of garlic extract (green). The results are presented as means ± SEM (*n* = 3). All the percentage inhibition of protein aggregation results (0.78–100 µg/mL garlic extract) were compared with G-HSA sample. Comparison between two groups was performed based on *t* test, and significance was defined as \* *p* < 0.05, \*\* *p* < 0.01, \*\*\* *p* < 0.001. 2.3.4. Amyloid Structure Inhibition **Figure 5.** Percentage aggregation vs. concentration of garlic extract. Native HSA and G-HSA were incubated for 10 weeks and served as negative and positive controls, respectively. G-HSA was incubated with various concentrations (0–100 µg/mL) of garlic extract (green). The results are presented as means ± SEM (*n* = 3). All the percentage inhibition of protein aggregation results (0.78–100 µg/mL garlic extract) were compared with G-HSA sample. Comparison between two groups was performed based on *t* test, and significance was defined as \* *p* < 0.05, \*\* *p* < 0.01, \*\*\* *p* < 0.001. Congo red (CR) dye is used to determine how much of a protein's secondary structure has been altered. CR contacts hydrophobic clefts located in between beta fibrils and has a unique ability to bind to the protein sheet structure. After binding, the CR dye has a specific absorbance of 530 nm. In Figure 6, the findings of the CR binding experiment showed reduction in cross amyloid structure formation (33.26%) compared with positive controls (G-HSA). By masking the sites of glycation and limiting the surface area accessible by solvent, garlic extract reduced HSA fibrillation and perhaps prevented the transition from α-helix to β-sheet.

Congo red (CR) dye is used to determine how much of a protein's secondary struc-

Garlic extract (µg/mL)

0 10 20 **Figure 6.** Percentage amyloid structure vs. concentration of garlic extract. Native HSA and G-HSA were incubated for 10 weeks as negative and positive controls, respectively. G-HSA was incubated with various concentrations (0–100 µg/mL) of garlic extract (green). The results are presented as means ± SEM (*n* = 3). All the percentage amyloid structure inhibition results (0.78–100 µg/mL garlic extract) were compared with G-HSA sample. Comparison between two groups was performed based on *t* test, and significance was defined as \* *p* < 0.05*.* **Figure 6.** Percentage amyloid structure vs. concentration of garlic extract. Native HSA and G-HSA were incubated for 10 weeks as negative and positive controls, respectively. G-HSA was incubated with various concentrations (0–100 µg/mL) of garlic extract (green). The results are presented as means ± SEM (*n* = 3). All the percentage amyloid structure inhibition results (0.78–100 µg/mL garlic extract) were compared with G-HSA sample. Comparison between two groups was performed based on *t* test, and significance was defined as \* *p* < 0.05.
