Comparative evaluation of St. John's wort from different Italian regions

Flowers and fruits of St. John's wort collected in different Italian regions were evaluated for their naphtodianthrone (hypericin and pseudohypericin), phloroglucinol (hyperforin and adhyperforin) and flavonol (rutin, quercetin, quercitrin, isoquercitrin and hyperoside) content. The quantitative evaluation was performed by HPLC-DAD. The crude drug collected at the fruit ripening period had the highest content in phloroglucinols and the lowest level of both naphtodianthrones and flavonols. Phloroglucinols peaked in the samples collected in Puglia followed by Lombardia and Veneto, while hypericins and flavonols were highest in the samples harvested in Sardegna and Trentino.