The resin of the tree Araucaria araucana (Araucariaceae) is used by the Mapuche Amerindians in southern Chile and Argentina to treat ulcers and has been shown to display a gastroprotective effect in animal models. A study was undertaken to isolate, identify and assess the gastroprotective effect of the resin constituents and its semisynthetic derivatives as well as to evaluate the cytotoxicity of the products in cell cultures. Eleven diterpenes (ten labdane and a pimarane) were isolated from a resin sample collected in Chile. The labdane derivatives 15-acetoxylabd-8(17)-en-19-ol as well as 15,19-diacetoxylabd-8(17)-en are reported for the first time as natural products. Six diterpenes previously described from other plant sources are reported for the first time for the A. araucana resin. The structure of all compounds was elucidated by spectroscopic means. Some 24 diterpenes isolated/prepared in amounts over 10 mg were evaluated for gastroprotective effects in the ethanol/HCl-induced ulcer model in mice at 100 mg/kg. The highest gastroprotective activities were provided by 15-hydroxyimbricatolal, 15-acetoxyimbricatolal, 15-acetoxylabd-8(17)-en-19-oic acid methyl ester and 15-acetoxy-19-labdanoic acid, all of them being as active as the reference drug lansoprazole at 20 mg/kg. The cytotoxicity of 30 diterpenes as well as lansoprazole was assessed towards human lung fibroblasts (MRC-5) and 26 compounds were evaluated on the human gastric epithelial cell line AGS by means of the neutral red uptake assay. A concentration-dependent cell viability inhibition was found with IC 50 values ranging from 27 up to > 1000 µm. The relationship between the cytotoxicity data and lipophilicity of the products is also discussed.

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A B S T R A C TThe "red chilto" (Solanum betaceum Cav) is a native fruit from the Yungas forest of Argentina. Red chilto is a neglected and underutilized native species (NUS). The objective of this work was to evaluate the potentiality of pulp, seed and skin from "red chilto" as a functional food ingredient to add value to a native resource of Argentine Yungas to promote sustainable integral use of it. The powders have low carbohydrate and sodium content and are a source of vitamin C, phenolic acids (rosmarinic acid and caffeoylquinic acid), anthocyanins, condensed tannins, carotenoids, potassium, and fiber. The phenolics of chilto powders showed, before and after simulated gastroduodenal digestion, antioxidant activity (ABTS þ ; H 2 O 2 ; O 2 ; HO ) and were able to inhibit enzymes related to metabolic syndrome, such as α-glucosidase, α-amylase and lipase. Chilto powder showed hypoglycemic effect by increasing glucose adsorption, decreasing glucose diffusion rate and by promoting glucose transport across the cell membrane. These results suggest the potential of Argentinean "red chilto" fruits as functional food ingredients or dietary supplements to prevent metabolic syndrome principally by its antioxidant, hypoglycemic and hypolipemic effects.

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Plants belonging to the Amaryllidaceae family have been shown to be a good source of biologically active alkaloids. The effect of 20 Amaryllidaceae alkaloids on the blood pressure of normotensive rats was assessed. The compounds evaluated belong to the lycorine, homolycorine, galanthamine, crinane, tazettine and miscellaneous skeletal types. At 1.5 mgkg−1, eight of the alkaloids assayed showed a significant effect on the arterial pressure of normotensive rats. Seven elicited a hypotensive response > 20%, with a lasting time ranging from 2.0 to 36.0 min while crinamine showed a hypertensive effect. These findings support the potential of Amaryllidaceae alkaloids as hypotensive drugs.

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Seven compounds belonging to different structural skeletons were isolated from Microsphaeropsis olivacea grown in liquid and solid media. The enalin derivative 7-hydroxy-2,4- dimethyl-3(2H)-benzofuranone is reported for the first time, while additional spectroscopic information is provided for the acetates of botrallin and ulocladol. The activity of the isolated compounds was assessed towards the enzyme acetylcholinesterase (AChE) and their cytotoxicity against human lung fibroblasts. Graphislactone A and botrallin presented a moderate activity towards AChE, with IC50 of 8.1 and 6.1 μg/ml (27 and 19 μᴍ, respectively). Under the same experimental conditions, the IC50 of the standard inhibitor galanthamine was 3 μg/ml. The cytotoxicity of both compounds was > 1000 and 330 μᴍ, respectively. None of the compounds was promising as antibacterial or antifungic against phytopathogenic fungi and bacteria. Botrallin and graphislactone A were detected in the liquid potato-dextrose and yeast extract/ malt extract/dextrose as well as on a solid substrate (rice). Butyrolactone I was obtained from the fungus growing on solid medium.

A. FournetInstitut Francais de Recherche Scientifique pour le Dtveloppement en Cooptration (ORSTOM), CP 97. Asunci6n. ParaguayThe activity of jatrogrossidione, the main diterpene of Jatropha grossidentutu and jatrophone from Jutropha isabellii was determined against Leishmania and Trypanosoma eruzi strains in vitro as well as against Leishmania amazonensis in vivo. Jatrogrossidione showed a strong in vitro leishmanicidal and trypanocidal activity with IC,, of 0.75 and 1.5-5.0 pg/mL, respectively. Under similar conditions, the IC,, of glucantime, ketoconazole and pentamidine towards Leishmania strains were >loo, 50-100 and 1 pg/mL, respectively. The IC,, of jatrogrossidione was ~0 . 2 5 pglmL against amastigote forms of Leishmania infecting macrophages, with toxicity at concentrations higher than 0.5 pg/mL. BALB/c mice infected with L. amazonensis strain PH 8 were treated 24 h after infection with jatrogrossidione and jatrophone for 13 consecutive days. Jatrophone at 25 mg/kg/day subcutaneously administered was significantly active (pcO.05) against the virulent strain P H 8 of L. arnazonesis; it was more active than Glucantime at 112 mg Sb' per kg/day. Subcutaneous administration of jatrophone, however, proved to be too toxic under our assay conditions. Assays of single local treatment on the footpad infection 2 weeks after inoculation of L amazonensis indicated that jatrogrossidione and jatrophone were inactive at the selected doses.