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Penicillium janczewskii K. M. Zalessky was isolated as an endophytic fungus from the phloem of the Chilean gymnosperm Prumnopitys andina. When grown in liquid yeast extract-malt extract-glucose broth, the fungus produced two main secondary metabolites. The compounds were for the first time isolated from this species and identified by spectroscopic methods as pseurotin A and cycloaspeptide A. This is the first report on the production of cyclic peptides by endophytic fungi from Chilean gymnosperms. Pseurotin A and cycloaspeptide A presented low cytotoxicity towards human lung fibroblasts with IC50 > or = 1000 microM. Pseurotin A showed a moderate effect against the phytopathogenic bacteria Erwinia carotovora and Pseudomonas syringae, with IC50 values of 220 and 112 microg ml(-1), respectively.

An in vitro propagation system was developed to obtain shoot and root cultures from the Andean spice Sanicula graveolens (Apiaceae). Propagation of shoots, roots and plantlets was achieved by the temporary immersion system. The free radical scavenging effect of the methanol/water (7:3 v/v) extracts was determined by the discoloration of the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH). Total phenolic, flavonoid, chlorogenic acid (CA) and quercetin 3-O-glucoside content in the samples was assessed by spectrophotometry and DAD-HPLC analysis, respectively. On a dry weight basis, the crude extracts showed total phenolic values ranging from 3.57 to 6.93%, with highest content for the root culture sample. Total flavonoid content ranged from 1.23 to 2.23% and was lower for the root culture. Chlorogenic acid and neochlorogenic acid were identified by TLC in all samples. Highest free radical scavenging effect was observed for the root culture which also presented the highest CA content. Two of the shoot culture samples, with similar IC50 values in the DPPH discoloration assay, also presented close quercetin-3-O-glucoside content.

The biomass production of Cymbopogon citratus shoots cultivated in bioreactors according to the temporary immersion (TIS) principle was assessed under different growth conditions. The effect of gassing with CO2-enriched air, reduced immersion frequency, vessel size and culture time on total phenolic and flavonoid content and free radical scavenging effect of the methanolic extracts was measured. From the TIS-culture of C. citratus, seven compounds were isolated and identified as caffeic acid (1), chlorogenic acid (2), neochlorogenic acid (3), p-hydroxybenzoic acid (4), p-hydroxybenzoic acid 3-O-beta-D-glucoside (5), glutamic acid (6) and luteolin 6-C-fucopyranoside (7). The occurrence of compounds 1-7 and their variability in C. citratus grown under different TIS conditions was determined by HPLC. The free radical scavenging effect of the methanolic extract and compounds was measured by the discoloration of the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH). The main metabolites in 6- and 8-week-old cultures, both in 5 and 10 1 vessels, were chlorogenic acid (2) (100-113 mg%) and neochlorogenic acid (3) (80-119 mg%), while in the cultures with CO2-enriched air and reduced immersion frequency the main compound detected in the extracts was glutamic acid (6) (400 and 670 mg% for the green and white biomass and 619 and 630 mg% for the green and white biomass, respectively). The most active compounds, as free radical scavengers, in the DPPH discoloration assay were caffeic acid (1), chlorogenic acid (2), neochlorogenic acid (3) and the flavonoid luteolin 6-C-fucopyranoside (7).

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 IC50 values ranging from 27 up to > 1000 microM. The relationship between the cytotoxicity data and lipophilicity of the products is also discussed.

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 microg/ml (27 and 19 microM, respectively). Under the same experimental conditions, the IC50 of the standard inhibitor galanthamine was 3 microg/ml. The cytotoxicity of both compounds was > 1000 and 330 microM, 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.

Tagetes mendocina (Asteraceae) is a medicinal plant widely used in the Andean provinces of Argentina. Preliminary assays showed free radical scavenging activity in the methanol extract of the aerial parts, measured by the decoloration of a methanolic solution of the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and scavenging of the superoxide anion. Assay-guided isolation led to 4'-hydroxyacetophenone (1), protocatechuic acid (2), syringic acid (3), patuletin (4), quercetagetin 7-O-beta-D-glucoside (5), patuletin 7-O-beta-D-glucoside (6) and axillarin 7-O-beta-D-glucoside (7) as the free radical scavengers and antioxidant compounds from Tagetes mendocina. On the basis of dry starting material, the total phenolic content of the crude drug was 3.00% with 0.372% of flavonoids. The content of compounds 1-7 in the crude drug was 0.008, 0.015, 0.010, 0.029, 0.238, 0.058 and 0.017%, respectively. Quercetagetin 7-O-beta-D-glucoside proved to be the main free radical scavenger of the extracts measured by the DPPH decoloration test as well as for quenching the superoxide anion and inhibition of lipoperoxidation in erythrocytes. In the lipid peroxidation assay the percentual inhibition was related with the number of methoxy groups in the molecule, ranging from 86% for the quercetagetin glucoside to 67% for the monomethoxylated and 31% for the dimethoxylated derivative. The compounds showed low cytotoxicity towards human lung fibroblasts with IC50 > 1 mM for compounds 1-3 and 0.24 to 0.52 mM for the flavonoids 4-7.