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Hypericum species (Hypericaceae) are a group of important plants with medicinal, edible, and ornamental values. A phytochemical study on the whole plants of H. hengshanense W. T. Wang, a species endemic to China, led to the isolation and elucidation of 25 monoterpenoid acylphloroglucinols (MAPs). Among them, 10 are undescribed compounds, namely hyphengshanols A–D, (+)-empetrilatinol A, (−)-empetrilatinol B, (−)-hyperjovinol A, (9 S ,2′ S)-dauphinol F, and (8 R ,2′ S)-empetrikathiforin. In addition, the absolute configurations of other six compounds were firstly determined in the current study. The structures were established by ultraviolet (UV), high resolution electrospray ionization mass spectrum (HR-ESI-MS), and nuclear magnetic resonance spectroscopy (NMR) data. The absolute configurations were determined by experimental and calculated electronic circular dichroism (ECD) data analyses. Cytotoxicity assays on five human cell lines HL-60, A549, SMMC-7721, MDA-MB-231, and SW480 revealed that 16 compounds exhibited broad-spectrum antiproliferative activities with IC 50 ranging from 7.54 to 45.70 μM. Ten undescribed monoterpenoid acylphloroglucinols and 15 known analogs were isolated and identified, including six pairs of stereoisomers. Their cytotoxicity against five cancer cell lines was evaluated. [Display omitted] • MAPs were isolated from Hypericum hengshanense including 10 undescribed ones. • The absolute configurations of 16 MAPs were determined by ECD calculations. • Six pairs of stereoisomers were separated via chiral-phase HPLC. • Sixteen isolates showed cytotoxicity against five cancer cell lines. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance The leaves of Phaleria nisidai Kaneh. (Thymelaeaceae) are brewed into a tea commonly used as a tonic, strengthening beverage and immune enhancer in Palau, Micronesia. Recently, the leaves of P. nisidai have been shown to contain toxic daphnane diterpene esters which may pose a public health threat to Palauans. Aims of the study This project documents the use frequency, preparation and side effects of P. nisidai . The content of daphnane diterpene esters in aqueous and methanol extracts and infusions prepared by healers in Palau is compared to assess the risk of daphnane ingestion associated with traditional consumption. Quantitative results are correlated with an in vitro assessment of the immunomodulating activity of the extracts. Materials and methods Research participants, comprising traditional healers and laypeople, were interviewed concerning use patterns and side effects of P. nisidai . Several traditional healers prepared and provided boiled tea samples for chemical analysis. Leaves were collected and methanolic and aqueous extractions were prepared in the laboratory. Peripheral blood mononuclear cells (PBMCs) were cultured with various concentrations of methanol and aqueous leaf extracts and their output of IFNγ was measured using ELISA. Cell proliferation was also assessed using the MTT assay. The concentration of selected daphnane diterpene esters in healer-prepared infusions, lab methanol and lab aqueous extracts was quantified using ultraperformance liquid chromatography-mass spectrometry-triple quadrupole detection (UPLC-MS-TQD). Results Through structured interviews it was determined that P. nisidai tea was used frequently, with many participants drinking it daily. The reported side effects were mild, and with the exception of diarrhea ( n =2), no side effect was mentioned more than once. Methanol extracts contained 4.0 μg simplexin, 17.6 μg acetoxyhuratoxin and 2.3 μg huratoxin per g dry leaf material. In traditional water infusions provided by healers and in standardized lab-prepared aqueous extracts all three compounds were below the limit of detection (16.3 ng/mL) using our UPLC-MS-TQD method. Methanol and aqueous extracts increased the release of IFNγ by PBMCs ( p <0.05); however, methanol extracts were significantly more active than aqueous extracts ( p <0.05). Methanol and aqueous extracts significantly increased proliferation of PBMCs, causing at least 60% more cell proliferation than negative control ( p <0.05). Conclusions The presence of daphnane diterpene esters in a frequently consumed traditional beverage was initially viewed as a public health concern, though interview data reveal that Palauans do not observe toxicity or side effects associated with their use of P. nisidai tea. Concurrently, daphnanes are present in methanolic extracts but not detected in aqueous preparations indicating that the traditional method of preparation avoids the extraction of these potentially toxic compounds, while still maintaining immunostimulant activity. [ABSTRACT FROM AUTHOR]

Abstract: Despite persistent questions about the safety of black cohosh (Actaea racemosa L., syn. Cimicifuga racemosa L.), its products continue to be one of the most popular botanical supplements in the United States market. Black cohosh products have been associated with cases of liver toxicity, but subsequent evaluation found some products to be adulterated with other related plants from the same genus. US FDA regulations require that black cohosh products be unadulterated, and correct identification of different species of Actaea is a key first step for their good manufacturing practice. We have developed a phytochemical method to distinguish four different groups of Actaea, including: species other than A. racemosa, Asian species, A. racemosa, and North American species other than A. racemosa. Using HPLC–TOF-ESI-MS technique and principal component analysis, we identified 15 chemical markers (1–3, 5–6, 8–10, 12, 16–21). Three marker compounds were unambiguously identified using authentic standards, and 12 marker compounds were tentatively identified by comparison of fragmentation patterns with previously reported data. The presence of these marker compounds is critical for discrimination among the four groups of closely related plants. The use of metabolic profiling to distinguish black cohosh from related species of Actaea has broader implications in the identification of markers to help authenticate other important medicinal plants. [Copyright &y& Elsevier]

Abstract: Cinnamomum carolinense, locally known as madeu, is a tree endemic to the volcanic mountains of the Island of Pohnpei in the Eastern Carolines of the South Pacific. The bark is harvested from trees and brewed to make a medicinal tea and hot beverage that is regularly consumed. Many species of Cinnamomum contain the known hepatocarcinogen safrole, sparking concern regarding habitual consumption of this beverage. HPLC-PDA analysis confirmed the presence of the carcinogen in alcoholic extracts of Cinnamomum carolinense bark shavings (0.435%, w/w), but safrole was not detected in the tea. The limit of detection and limit of quantitation of safrole were determined to be 1.25 and 3.75μg/mL, respectively. The traditional preparation method, which boils the bark shavings, degrades the safrole. [Copyright &y& Elsevier]