Saponins and Flavonoids from an Infusion of Herniaria hirsuta

Stone diseases present a major health problem in the Western society, since both urinary and biliary stones occur with a relatively high prevalence of 10-12 % and 10-20 %, respectively, and demonstrate a high recurrence rate. At the moment treatment is mainly based on interventional procedures, or prophylactic and dissolution therapy. However, many of the current drugs cause severe side effects, and therefore, there is an increasing interest in natural medicines. At the moment no registered herbal medicinal products are available for treatment of gallstones. Since an infusion of Herniaria hirsuta L. has a proven efficacy against urolithiasis and cholelithiasis, its phytochemical composition has been investigated. Two previously undescribed triterpene saponins, 28-O-{[β-D-xylopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 2)]-[β-D-glucopyranosyl-(1-6)]-β-D-glucopyranosyl}-medicagenic acid and 3-O-[α-L-rhamnopyranosyl-(1 → 3)-β-D-glucuronopyranosyl]-28-O-{[β-D-glucopyranosyl-(1 → 3)-β-D-xylopyranosyl-(1 → 4)]-[β-D-apiofuranosyl-(1 → 3)]-α-L-rhamnopyranosyl-(1 → 2)-β-D-fucopyranosyl}-medicagenic acid and three known flavonoids, quercetin-3-O-(2″-O-α-L-rhamnopyranosyl)-β-D-glucuronopyranoside, rutin, and narcissin (isorhamnetin-3-O-rutinoside), were isolated using flash chromatography and successive semi-preparative HPLC and were well characterized by MS and 1D and 2D NMR spectroscopic techniques. These findings could contribute to the development of a standardized extract that can be used in prophylaxis and treatment of gall and kidney stones.