I assume that you want to apply make-gold class when IsGranted value is true. If this is the case, try this:
<mat-row *matRowDef="let row; columns: displayedColumns;" [ngClass]="{'make-gold': row.IsGranted }">
See also stackblitz demo.
EDIT
There is also a shorthand syntax:
<mat-row ... [class.make-gold]='row.IsGranted' [class.another-class]="true">