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The chemical composition of the essential oils from the leaves from three different populations of Psidium laruotteanum Cambess. (Myrtaceae) from the Brazilian Cerrado were analysed by GC-FID and GC-MS. Forty-five components were identified in the oils. The oil yields were 0.3% (dry weight basis). The oil was rich in monoterpenes and major compounds identified were p-cymene (19.4-34.8%), 1,8-cineole (6.9-19.2%) and α-pinene (9.2-11.4%). Although collected in different locations and years, the essential oils composition were quite similar, both qualitative and quantitatively.

Divalent cadmium compounds, particularly CdO, were used as Lewis-acid catalysts in the hydrolysis, esterification, and transesterification of pure triacylglycerides or fatty acids obtained from neutralized soybean oil, as well as mixtures of these substrates. In more than one step, reaction yields of up to 98% in fatty acids or fatty acid methyl esters were achieved. To study the use of these reactions for the development of technologies for biodiesel production from low-grade starting materials, a study was also carried out using a real sample with a high content of free fatty acids from the Brazilian savanna palm-tree oil called Macauba (Acrocomia sclerocarpa M.). Using multistep, sequential, or combined (one-pot) reaction processes, it was possible to obtain an overall reaction yield of up to 98% in methyl esters.

The chemical profile of the essential oil obtained from leaves and inflorescences of Psidium myrsinites DC. (Myrtaceae) growing wildly in the Brazilian Cerrado was analyzed by GC/FID and CG/MS. The essential oil had a slimy and translucent appearance. The oil yield was 0.1% and the main components were oxygenated sesquiterpenes (68.2%) and non-oxygenated sesquiterpenes (18.3%). Caryophyllene oxide (26.1%), humulene epoxide II (8.8%), β-caryophyllene (7.4%) and α-caryophyllene (5.4%) were the major compounds. It is worth to notice that the most abundant substances have very close structures. The oil yield and composition was very similar to other species belonging to the same genus.