Phenolic Constituents of the Chilean Herbal Tea Fabiana imbricata R. et P.

Schmeda-Hirschmann, G (reprint author), Univ Talca, Inst Quim Recursos Nat, Lab Quim Prod Nat, Casilla 747, Talca, Chile."Pichi" or "pichi romero" (Fabiana imbricata R. et. P., Solanaceae) is a Chilean plant used as a tea in the Andean regions of Chile and Argentina. A very simple and direct method was developed for the qualitative analysis of polyphenols in the tea by high-performance liquid chromatography (HPLC) with diode array detection and electrospray ionization tandem mass spectrometry. The phenolic constituents identified in the teas were chlorogenic acid (3-O-caffeoylquinic acid), p-hydroxyacetophenone, scopoletin and quercetin derivatives. The glycosides were mainly glucosides from p-hydroxyacetophenone and scopoletin while di- and tri-glycosides from quercetin were the main flavonoids. The content of the main phenolic compounds in the teas (g/100 g lyophilized infusion) was 0.8-1.9 % for scopoletin, 0.4-6.2 % for p-hydroxyacetophenone and 2.1-4.3 % for rutin, respectively. The health-promoting properties reported for this herbal tea can be associated with the presence of several phenolics with known antioxidant, diuretic and antiinflammatory activity

Anti-<i>Acanthamoeba</i> Activity of Brominated Sesquiterpenes from <i>Laurencia johnstonii</i>

Focused on our interest to develop novel antiparasistic agents, the present study was aimed to evaluate the biological activity of an extract of Laurencia johnstonii collected in Baja California Sur, Mexico, against an Acantamoeba castellanii Neff strain. Bioassay-guided fractionation allowed us to identify the amoebicidal diastereoisomers &#945;-bromocuparane (4) and &#945;-isobromocuparane (5). Furthermore, bromination of the inactive laurinterol (1) and isolaurinterol (2) yielded four halogenated derivatives, (6)&#8315;(9), which improved the activity of the natural sesquiterpenes. Among them, the most active compound was 3&#945;-bromojohnstane (7), a sesquiterpene derivative which possesses a novel carbon skeleton johnstane

Laurequinone, a Lead Compound against <i>Leishmania</i>

Among neglected tropical diseases, leishmaniasis is one of the leading causes, not only of deaths but also of disability-adjusted life years. This disease, caused by protozoan parasites of the genus Leishmania, triggers different clinical manifestations, with cutaneous, mucocutaneous, and visceral forms. As existing treatments for this parasitosis are not sufficiently effective or safe for the patient, in this work, different sesquiterpenes isolated from the red alga Laurencia johnstonii have been studied for this purpose. The different compounds were tested in vitro against the promastigote and amastigote forms of Leishmania amazonensis. Different assays were also performed, including the measurement of mitochondrial potential, determination of ROS accumulation, and chromatin condensation, among others, focused on the detection of the cell death process known in this type of organism as apoptosis-like. Five compounds were identified that displayed leishmanicidal activity: laurequinone, laurinterol, debromolaurinterol, isolaurinterol, and aplysin, showing IC50 values against promastigotes of 1.87, 34.45, 12.48, 10.09, and 54.13 µM, respectively. Laurequinone was the most potent compound tested and was shown to be more effective than the reference drug miltefosine against promastigotes. Different death mechanism studies carried out showed that laurequinone appears to induce programmed cell death or apoptosis in the parasite studied. The obtained results underline the potential of this sesquiterpene as a novel anti-kinetoplastid therapeutic agent