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Argentina is one of the major producers of soybean in the world, this generates a high global demand for this crop leading to find it everywhere, even close to human activities involving pollutant emissions. This study evaluated heavy metal content, the transfer of metals and its relation to crop quality, and the toxicological risk of seed consumption, through soil and soybean sampling. The results show that concentrations of Pb and Cd in soils and soybeans at several sites were above the maximum permissible levels. The heavy metal bioaccumulation depending on the rhizosphere soil compartment showed significant and high regression coefficients. In addition, the similar behavior of Cd and Zn accumulation by plants reinforces the theory of other studies indicating that these metals are incorporated into the plant for a common system of transport. On the other hand, the seed quality parameters did not show a clear pattern of response to metal bioacumulation. Taken together, our results show that soybeans grown nearby to anthropic emission sources might represent a toxicological hazard for human consumption in a potential Chinese consumer. Hence, further studies should be carried out taking into account the potential negative health effects from the consumption of soybeans (direct or indirect through consumption of meat from cattle) in these conditions., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Seven new withanolides (1-7) were isolated from the aerial parts of Jaborosa caulescens var. caulescens and Jaborosa caulescens var. bipinnatifida. Three of the new compounds are related to jaborosalactones R, S, and T with a delta-lactone side chain and a hemiketal (or ketal) ring formed between a 21-hydroxyl and a 12-ketone (1-3). Compounds 4-7 are trechonolide-type withanolides with a gamma-lactone side chain and a hemiketal (or ketal) ring formed between a 22-hydroxyl and a 12-ketone. Compounds 4 and 5 also contain a hydroxyl group at C-21. Compounds 1, 2, and 7 showed selective phytotoxicity toward monocotyledonous and dicotyledonous species.

The sesquiterpenoid fractions from the chloroform extracts of roots and aerial parts of the weed Cyrtocymura cincta (Griseb.) H. Robinson (Compositae) were tested to observe the effects on seed germination and growth of three dicot and four monocot species. Promotion and inhibition effects were observed according to the examined compound, specific seed or cultivar, and concentration.

Toxic disease in livestock caused by the shrubs Baccharis coridifolia and Baccharis artemisioides is very common in Argentina. The toxicity of Argentinian and Brazilian B. coridifolia plants and of Argentinian B. artemisioides was investigated. The toxicogenic capacity of 15 endothyte isolates of Ceratopicnidium baccharidicola from B. coridifolia was determined. Roridins and verrucarins were analyzed by thin-layer chromatography using a modified Jarvis method. One-hundred per cent of Argentinian B. coridifolia plants were positive for roridins (RA and RE) and verrucarins (VA and VJ), 16.2% for RD and 2.7% for RH. All of the Brazilian B. coridifolia plants were positive only for roridins. In B. artemisioides plants, RA, RE and RD were present in higher concentrations than VA and VJ, and all of them were more concentrated than in B. coridifolia. One-third of the endophyte isolates were toxicogenic for the same roridins and verrucarins, but in very low concentrations. This is the first report of macrocyclic trichothecenes in B. artemisioides, and a new report of B. coridifolia macrocyclic trichothecenes in Argentina.