[Efficient Preparation of Ephedrine Alkaloids-free Ephedra Herb Extract and Its Antitumor Effect and Putative Marker Compound].

Ephedra Herb is a crude drug for the treatment of headache, bronchial asthma, nasal inflammation, and the common cold. Although it has been considered that ephedrine alkaloids (EAs) are the principal active ingredients of Ephedra Herb, EAs are known to induce palpitations, hypertension, insomnia, and dysuria as major side effects. Therefore, the administration of EAs-containing drugs to patients with cardiovascular-related diseases is strongly contraindicated. Previously, we isolated herbacetin 7-O-neohesperidoside from Ephedra Herb. In addition, we found that herbacetin, a flavonoid aglycone in Ephedra Herb, had antiproliferative and analgesic effects. Therefore, the prospect of preparing safer natural medicines without the adverse effects associated with EAs was appealing. In this symposium review, to achieve the aim of producting a clinically useful Ephedra Herb extract with none of the adverse effects associated with EAs, I present an efficient preparation method of EAs-free Ephedra Herb extract, together with its chemical composition, antiproliferative effects, and a putative marker for quality control.