Sarcocornia ambigua is a perennial glasswort, native of South America and a potential new seed-oil crop and forage for direct irrigation with salt water. Small seeds develop inside fertile segments of its cylindrical leafless shoots and, at the harvest, seeds are typically mixed with remnant cellulose material difficult to separate. This work evaluated different extraction methods and the composition of total esterified fatty acids in a meal of ground fertile shoots of S. ambigua, seeking for an alternative primary matter and larger yield of total lipids. The highest lipid yield was obtained with a chloroform:methanol mixture (2:1)(v/v) (5.2% of dry weight). The most abundant polyunsaturated fatty acids in the meal were linoleic acid (C18:2; 21.4%) and oleic acid (C18:1; 18.3%). Fifty six percent of the lipids in S. ambigua meal were saturated and palmitic acid (C16:0) was the main fraction (19.8%). Long-chain fatty acids (≥ C20) represented 29.5% of the lipids. Most abundant long-chain fatty acids were behenic acid (C22:0; 7.1%), lignoceric acid (C24:0; 5.3%) and montanic acid (C28:0; 4.0%). The percentage of saturated lipids in S. ambigua meal was higher than that of vegetable oils with a MUFA nutritional profile and some of these lipids have known bioactive properties.

This paper reports the study of structural and luminescence parameters of a seven-coordination compound containing b-diketone butyl methoxy-dibenzoyl-methane (bmdm) and triphenylphosphine oxide (tppo), both acting as antennae. The complex was obtained by substitution of water molecules in the [RE(bmdm) 3 (H 2 O) 2 ] precursor, where RE = Eu 3+ or Gd 3+ . The structural data determined by X-ray monocrystal diffraction reveal that the compound crystallizes in a triclinic space group P 1 and the coordination polyhedron is near a capped trigonal prism, with a symmetry site near a C 2v point group. The ground state geometry was determined using Sparkle/AM1 implemented in mopac2009 software, and compared with that obtained by monocrystal. The triplet (T) and singlet (S) levels were determined using INDO/S-CIS implemented in the Zindo software, the results obtained are very close to the experimental measurements. The intensity parameters O 2 and O 4 were calculated from emission spectrum. The high value of the O 2 parameter (37.2 Â 10 À20 cm 2 ) shows a highly polarizable environment around the europium ion and a high degree of covalence between the ligand and metal, showing that tppo molecules contribute to an increase in the covalence between the metal and ligand. The transfer rates show a predominance in the transfer process when compared with back transfer ones, with the main channel of transfer processes: T

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This paper discusses about the improvement of electrochemical characteristics of graphite paste electrode chemically modified with chitosan through physical crosslinking of the biopolymer with sodium tripolyphosphate. Biopolymer characterizations were performed by scanning electron microscopy, Fourier transform infrared spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The electrochemical characterization of Pb with graphite paste electrode modified with chitosan crosslinked with sodium tripolyphosphate (GPE-CTS-TPP) showed that the process is quasireversible, controlled by adsorption and involves the transfer of two electrons. Additionally, the physical crosslinking process decreased the electrode resistance as well as improved the electron transfer rate. Once the GPE-CTS-TPP showed enhanced morphological and electrochemical characteristics, it was applied for Pb determination by square wave anodic stripping voltammetry. The method presented appropriate accuracy (recoveries from 95 to 108% and concordance with comparative method between 90 and 107%), high sensitivity (limit of detection and quantification of Pb were 0.73 and 2.44 μg L-1 , respectively) and could be applied to analytical determinations.

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