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Omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) are essential fatty acids required in healthy balanced diets for humans. To induce sustained production of n-3 LC-PUFA in gilthead seabream (Sparus aurata), chitosan-tripolyphosphate (TPP) nanoparticles encapsulating plasmids expressing fish codon-optimised Caenorhabditis elegans FAT-1 and FAT-2 were intraperitoneally administered every 4 weeks (3 doses in total, each of 10 μg plasmid per g of body weight). Growth performance and metabolic effects of chitosan-TPP complexed with pSG5 (empty plasmid), pSG5-FAT-1, pSG5-FAT-2 and pSG5-FAT-1 + pSG5-FAT-2 were assessed 70 days post-treatment. Tissue distribution analysis showed high expression levels of fish codon-optimised FAT-1 and FAT-2 in the liver (> 200-fold). Expression of fat-1 and fat-1 + fat-2 increased weight gain. Fatty acid methyl esters assay revealed that co-expression of fat-1 and fat-2 increased liver production and muscle accumulation of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and total n-3 LC-PUFA, while decreased the n-6/n-3 ratio. Co-expression of fat-1 and fat-2 downregulated srebf1 and genes encoding rate-limiting enzymes for de novo lipogenesis in the liver, leading to decreased circulating triglycerides and cholesterol. In contrast, FAT-2 and FAT-1 + FAT-2 upregulated hepatic hnf4a, nr1h3 and key enzymes in glycolysis and the pentose phosphate pathway. Our findings demonstrate for the first time efficient and sustained production of EPA and DHA in animals after long-term treatment with chitosan-TPP-DNA nanoparticles expressing FAT-1 and FAT-2, which enabled the production of functional fish rich in n-3 LC-PUFA for human consumption. [ABSTRACT FROM AUTHOR]

In this contribution, the influence of Pulsed Electric Fields (PEF) of different intensities (3-9 kV/cm and 0-300 μs) on the extraction of Total Phenols from lemon peel residues by pressing was investigated. According to the cellular disintegration index, the optimum treatment time for the increase in permeability was determined as 30 pulses of 30 μs. It was determined that the effect of PEF was independent of lemon residue size. The effectiveness of pressing-assisted extraction was evaluated by measuring the Total Phenol Content (TPC), the real antioxidant capacity and the concentrations of the main lemon polyphenols, the flavonones hesperidin and eriocitrin. The variables studied in the extraction were time, pressure applied and intensity of the electric fields. This study concludes that electric field intensity of 7 kV/cm increased the efficiency of polyphenol extraction by 300%, giving maximum values of 84 mg of hesperidin in 100 g FW and 176 mg of eriocitrin in 100 g FW. Thus, it was concluded that PEF provides a new methodology to improve polyphenol extraction with a non-thermal, environment-friendly technology, and this represents a method for increasing economic benefits of industrial processes. [ABSTRACT FROM AUTHOR]