A free radical scavenging activity guided fractionation of the polar extract from roots of Limonium brasiliense (Plumbaginaceae) led to the isolation of five active compounds including: myricetin 3-O-α-rhamnopyranoside (1), (-)-epigallocatechin 3-O-gallate (2), (-)-epigallocatechin (3), (+)-gallocatechin (4) and gallic acid (5). These and other chemical constituents are reported for the first time for this species. The characterization of these compounds was achieved by spectroscopic methods (1H NMR, 13C NMR and UV).

The essential oil composition from the aerial parts of three Anacardiaceae growing in Bahía Blanca, Argentina was studied by gas chromatography and gas chromatography-mass spectrometry. The essential oils of S. longifolia and S. fasciculata have been studied for the first time. The major constituents were α-pinene (46.5%), -pinene (15.1%) and α-phellandrene (10.1%) for S. longifolia and limonene (10.9%), -phellandrene (6.16%) and α-phellandrene (5.6%) for S. fasciculata. The major components of the essential oil of S. areira were limonene (28.6%), α-phellandrene (10.1%), sabinene (9.2%) and camphene (9.2%) differing from the literature data. The essential oils from S. areira and S. longifolia exhibited a high biotoxicity in a brine shrimp assay with Artemia persimilis.

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The study was undertaken to quantify the effect of different controlled fire frequencies on foliar cover, density, individual basal area, and mortality of the most common perennial grass species in the semi-arid rangelands of the southern Caldenal in central Argentina over a 20-year period. Cover of bare soil was also assessed. The study comprised three fire treatments: (i) high fire frequency (controlled burns every 3–5 years; HFF); (ii) low fire frequency (controlled burns every 8 years; LFF); and (iii) unburned control (C). Fire treatments, regardless of frequency, induced an increase in foliar cover and density in desirable grasses, no changes in intermediate grasses, and a decrease in undesirable grasses. Individual basal area tended to be higher for desirable grasses and lower for intermediate and undesirable grasses when subject to fire. Most of the species under study exhibited higher mortality rates in the HFF treatment than in the LFF and C treatments. The results of the study suggest that recurrent controlled burns of moderate intensity may favour the herbage production of desirable perennial grasses. This, in turn, assuming appropriate grazing management, may have a beneficial impact on livestock production. Nevertheless, given the effects of fire on the cover of bare soil and mortality of grasses, further research is needed in order to determine the appropriate fire frequency in terms of rangeland sustainability.