African Yohimbe bark

I am inquiring about an herb found on the label for Supplement Facts and was hoping you can tell me anything about this ingedient "Africanyohimbe bark" standardized extract (4% total alkaloids). I would appreciate any information you can provide for me.

African yohimbe bark has been most commonly associated with herbal supplement products for the treatment of male impotence. Like Viagra, the drug has an effect on the cardiovascular system, and has a history of use for the treatment of angina. Presumably, it dilates the arteries thus enhancing the flow of blood.
According to the United States Food and Drug Administration, products sold in the U.S. purporting to contain the bark actually contain only the alkaloid, yohimbine hydrochloride. This may be significant because the bark contains many other alkaloids that may have a supporting effect. Yohimbine clearly is responsible for some of the medicinal effect, but yohimbe products are considered risky to take by the FDA, possibly because of the common practice of formulating products with the purified alkaloid and not the whole bark. In Africa, the whole bark has a long history of use for the treatment of male impotence and other ailments.