Which active ingredient is particularly noted in St. John's Wort?

St. John's Wort is particularly noted for the presence of hypericin, which is one of its primary active ingredients. Hypericin is a red pigment found in the plant that has been studied for its potential effects on mood regulation and its use in the treatment of mild to moderate depression. Research has suggested that hypericin may influence neurotransmitter systems in the brain, including serotonin, dopamine, and norepinephrine, contributing to its antidepressant effects.

In addition to hypericin, St. John's Wort contains other compounds, such as flavonoids, which have beneficial properties, but hypericin is the most recognized and studied for its specific role in the plant's therapeutic potential. The significance of hypericin in St. John's Wort and its pharmacological impact is what primarily sets it apart from the other components that could be present.