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This study reports the first quantification study of pseudohypericin (PsHyp) and hypericin (Hyp) inHypericum undulatumSchousb. ex Willdin vitrocultures developed by a Portuguese company. Both compounds were quantified by high-performance liquid chromatography and their levels were compared with those in commercial samples ofHypericum perforatum. PsHyp was found to be the major naphthodianthrone ofH. undulatum,with an average ratio of 3.73:1 compared to Hyp. Significant statistical differences were found between the content of Hyp and PsHyp inH. undulatumregenerated shoots compared toin vivosamples. The mean concentration of total Hyps varied from 178.41 to 358.93 µg g−1dry extract inH. undulatumregenerated shoots, which is on average two to three times less than naphthodianthrone levels found inH. undulatum in vivoandH. perforatumcommercial samples. However, none of the analysed samples presented the levels of Hyps required by the European and United States Pharmacopoeias. [ABSTRACT FROM PUBLISHER] more...

Water extracts of Hypericum foliosum (HF) from five Azorean Islands were analysed for their antioxidant activity and total phenolic contents. The results were compared with those from medicinal Hypericum species (H. perforatum, H. androsaemum and H. undulatum) and also with Azorean green tea. HF exhibited strong scavenging activity (87-91%) and moderate inhibition of linoleic acid oxidation (56-72%), and presented no significant difference to the other studied plants; in contrast, the synthetic antioxidant butylated hydroxyltoluene showed antioxidant activity values of 22% and 88%, respectively. The average value of phenolics in HF was higher than that in the other Hypericum species and lower than that in tea. Additionally, the phenolic profiles of the Hypericum species were compared by reverse phase-high performance liquid chromatography/ultraviolet (RP-HPLC/UV). The method presented permits the simultaneous determination of phenolic acids, flavonoids, hypericin and hyperforin within 55 min. The most similar profile was observed between HF and H. androsaemum. This study indicates that HF is a source of bioactive compounds with potential health benefits. [ABSTRACT FROM AUTHOR] more...