Final answer:
Herbal supplements that act like aspirin by inhibiting thromboxane A2 biosynthesis disrupt platelet aggregation for an extended period. Aspirin itself increases bleeding time and is ceased before surgery to avoid excessive bleeding.
Step-by-step explanation:
The herbal supplement that disrupts platelet aggregation for the longest time after discontinuation is likely one that inhibits the biosynthesis of thromboxane A2, similar to how aspirin works. Aspirin is known for its ability to interfere with platelet function by preventing the formation of thromboxane A2, a potent aggregating agent.
Due to this effect, aspirin increases the bleeding time and should not be used for 10-14 days before surgery to avoid excessive bleeding during or after the operation.