What goes into the Krebs cycle?

The main reactants that go into the Krebs cycle are acetyl-CoA and oxaloacetate. Acetyl-CoA is derived from the breakdown of glucose (via glycolysis and pyruvate decarboxylation), fatty acids, and amino acids. Oxaloacetate is already present in the cycle and combines with acetyl-CoA to form citrate, starting the cycle.