Neura Bragagnolo

A novel microwave assisted extraction (MAE) method for fish lipids was optimized by means of a central composite design and validated using a fish tissue standard reference material (SRM, 1946, NIST). Scanning electron microscopy showed that MAE caused total disruption of the fish tissue, thus lipid migration to the extraction solvent was more efficient and faster in comparison to the Folch method. The lipid content of the SRM obtained by MAE (10.1 ± 0.2 g/100 g) was similar to that declared on the certificate (10.2 ± 0.5 g/100 g). The use of microwave energy did not alter the fatty acid composition of the fish nor formed lipid oxidation derived compounds at higher levels than in the Folch method. The MAE method was applied to fishes with different lipid contents, tilapia, pacu, and hake. MAE is a fast and robust technique with low solvent consumption when compared to the Folch method.Practical applications: MAE presented the following advantages over the Folch method: the lipids can be extracted from up to 12 samples simultaneously, it reduces the extraction time by up to 90%, produces less residues, reduces solvent consumption proportionaly to the mass used by up to 25%, and contributes to a reduction in toxicity in the environment by substituting chloroform with ethyl acetate.The MAE method was applied to fishes with different lipid contents, tilapia, pacu, and hake.

The influence of green coffee genotype on the bioactive compounds and the in vitro antioxidant capacity against the principal reactive oxygen (ROO^•, H₂O₂, HO^•, and HOCl) and nitrogen (NO^• and ONOO^–) species of biological relevance was investigated. This is the first report on the capacity of green coffee to scavenge H₂O₂, HOCl, and NO^•. Variations in the contents of total chlorogenic acids (22.9–37.9 g/100 g), cinnamoyl–amino acid conjugates (0.03–1.12 g/100 g), trigonelline (3.1–6.7 g/100 g), and caffeine (3.9–11.8 g/100 g) were found. Hydrophilic extracts of Coffea canephora and Coffea kapakata were the most potent scavengers of ROO^•, H₂O₂, HO^•, NO^•, and ONOO^– due to their chlorogenic acid contents, which were, on average, 30% higher than those found in Coffea arabica and Coffea racemosa. The results showed that genotype is a determinant characteristic in the bioactive compound contents and consequently in the antioxidant capacity of green coffee.