Biodiesel is an alternative fuel obtained from different biomass sources and processes. Nowadays, this biofuel has gained importance due to environmental concerns and rising energy demand. In the biodiesel production chain, stability is a critical issue, as it is linked to the maintenance of its original properties. This work performed a study evaluating the influence of storage conditions on the quality aspects of biodiesel. Thus, different samples of biodiesel obtained from soybean and frying oils were produced and placed in containers made by plastic, glass and tin, and stored in presence or absence of an oxidative atmosphere, moisture and light. These samples were analyzed to evaluate the ester content, acidity, iodine value, kinematic viscosity and oxidative stability. The characterization with GC-MS and GC/FID were done aiming to determine the chemical composition. Blends with frying biodiesel into soybean biodiesel have also been produced in concentrations ranging from 1%, 5% and 10% (m/m) in order to evaluate the mixing effect. In the initial storage time, all tested parameters were in accordance to the legislation. Distinct behaviors were identified for each sample according to the container type, being the glass the most effective of them in maintenance of biodiesel characteristics.

The seed oils from four plants (Scheelea phalerata, Butia capitata, Syagrus romanzoffiana, Terminalia cattapa) found in Mato Grosso do Sul were extracted at good yields. Alkaline transesterification of these seed oils to esters using methanol and ethanol was studied and also produced good yields. Oleic acid (30.5/32.3%), lauric acid (30.7/32.9%) methyl and ethyl esters, were the main components of transesterification of the oils from Scheelea phalerata and Syagrus romanzoffiana. Lauric acid (42.2%), capric acid (15.9%) and caprylic acid (14.6%) methyl and ethyl esters were the main ester components of transesterification of the oil from Butia capitata. Oleic acid (37.8%), palmitic acid (33.5%) and linoleic acid (22.6%) methyl and ethyl esters were the main components of transesterification of oil from Terminalia catappa. Based on differential scanning calorimetry (DSC) studies, the first crystallization peak temperature of esters was observed. Esters derived from oils of the family Arecaceae (Scheelea phalerata, Butia capitata, Syagrus romanzoffiana) showed the lowest points of crystallization, despite having high levels of saturated fat. Esters of Terminalia cattapa oil, rich in unsaturated fat, showed the highest crystallization temperature. This difference in behavior is probably related to the high concentration of esters derived from lauric acid and palmitic acid.

GC/MS/FID analyses of volatile compounds from cladodes and inflorescences from male and female specimens of Baccharis trimera (Less.) DC. collected in the states of Paraná and Santa Catarina, Brazil, showed that carquejyl acetate was the primary volatile component (38% to 73%), while carquejol and ledol were identified in lower concentrations. Data were subjected to hierarchical cluster analysis and principal component analysis, which confirmed that the chemical compositions of all samples were similar. The results presented here highlight the occurrence of the same chemotype of B. trimera in three southern states of Brazil.