Síntesis del ácido iso-13-metil-tetradecanoico y sus triglicéridos

A new and more convenient synthesis of the isofatty acid 13-methyl-tetradecanoic acid and its triglyceride is described here. This isofatty acid is prepared through elongation of the undecanoic acid chain with isobutyraldehyde according to Wittig by the reaction between bromo-undecanoic acid ethyl ester-triphenylphosphonium salt and sodium methoxide followed by the addition of isobutyraldehyde. Its triglyceride is formed by the esterification of the free isofatty acid with glycerin without catalyst. Its purity was over 99% after high refining over activated silica gel. Total yield was estimated to be 22,8%.Una nueva y práctica síntesis del ácido graso iso-13-metil- tetradecanoico y sus triglicéridos se describe aquí. Este iso- ácido graso se prepara a través de la elongación de la cadena del ácido undecanoico con isobutiraldehido según Wittig por reacción entre la sal de bromuro de undecanoico etil-éster trifenilfosfonio y metilato sódio seguido de la adición de isobutiraldehido. Su triglicérido está formado por la esterificación del iso ácido graso libre con glicerina sin catalizador. Su pureza es superior al 99%, después de una alta refinación sobre gel de sílice activado. El rendimiento total se estimó en el 22,8%

Life cycle assessment of European anchovy (Engraulis encrasicolus) landed by purse seine vessels in northern Spain

Purpose: The main purpose of this article is to assess the environmental impacts associated with the fishing operations related to European anchovy fishing in Cantabria (northern Spain) under a life cycle approach. Methods: The life cycle assessment (LCA) methodology was applied for this case study including construction, maintenance, use, and end of life of the vessels. The functional unit used was 1 kg of landed round anchovy at port. Inventory data were collected for the main inputs and outputs of 32 vessels, representing a majority of vessels in the fleet. Results and discussion: Results indicated, in a similar line to what is reported in the literature, that the production, transportation, and use of diesel were the main environmental hot spots in conventional impact categories. Moreover, in this case, the production and transportation of seine nets was also relevant. Impacts linked to greenhouse gas (GHG) emissions suggest that emissions were in the upper range for fishing species captured with seine nets and the value of global warming potential (GWP) was 1.44 kg CO2 eq per functional unit. The ecotoxicity impacts were mainly due to the emissions of antifouling substances to the ocean. Regarding fishery-specific categories, many were discarded given the lack of detailed stock assessments for this fishery. Hence, only the biotic resource use category was computed, demonstrating that the ecosystems' effort to sustain the fishery is relatively low. Conclusions: The use of the LCA methodology allowed identifying the main environmental hot spots of the purse seining fleet targeting European anchovy in Cantabria. Individualized results per port or per vessel suggested that there are significant differences in GHG emissions between groups. In addition, fuel use is high when compared to similar fisheries. Therefore, research needs to be undertaken to identify why fuel use is so high, particularly if it is related to biomass and fisheries management or if skipper decisions could play a role.The authors thank the Ministry of Economy and Competitiveness of the Spanish Government for their financial support via the project GeSAC-Conserva: Sustainable Management of the Cantabrian Anchovies (CTM2013-43539-R) and to Pedro Villanueva-Rey for valuable scientific exchange. Jara Laso thanks the Ministry of Economy and Competitiveness of Spanish Government for their financial support via the research fellowship BES-2014-069368 and to the Ministry of Rural Environment, Fisheries and Food of Cantabria for the data support. Dr. Ian Vázquez-Rowe thanks the Peruvian LCA Network for operational support. Reviewers are also thanked for the valuable and detailed suggestions. The work of Dr. Rosa M. Crujeiras has been funded by MTM2016-76969P (AEI/FEDER, UE)

Performance of intensively farmed Murray cod Maccullochella peelii peelii (Mitchell) fed newly formulated vs. currently used commercial diets, and a comparison of fillet composition of farmed and wild fish

Murray cod is a top-order carnivore with high culture potential. Currently, there are no commercial diets formulated specifically for Murray cod. In this study, results of two growth trials on Murray cod (80&ndash;83.5-g mean initial weight), conducted in commercial settings, using two laboratory-formulated diets (DU1 and DU2; 48.9% and 49.1% protein, and 16.9% and 16.1% lipid, respectively, on a dry matter basis), and two commercial diets, formulated for other species (salmon &ndash; CD/S and barramundi &ndash; CD/B) but used in Murray cod farming are presented. The two commercial diets had less protein (46.6% and 44.4%) but higher lipid (21.7% and 19.5%). The energy content of the feeds tested was similar (about 20&ndash;22 kJ g&minus;1). The growth performance and feed utilization of Murray cod did not differ significantly amongst the diets, but the food conversion ratio and % protein efficiency ratio in fish fed the DU1 and DU2 diets were consistently better. There was significantly less carcass and muscle lipid deposition in fish fed with the latter diets. Of the fatty acids in muscle, the lowest amounts (in &mu;g mg lipid&minus;1) of n-3 (262.5&plusmn;2.9), n-6 (39.8&plusmn;0.9) and polyunsaturated fatty acid (PUFA) (302.3&plusmn;3.8) were observed in fish fed CD/S, and the highest in fish fed DU2 and CD/B. Fatty acids 16:0 and 18:0, 18:1n-9 and 16:1n-7, and 22:6n-3, 20:5n-3, 22:5n-3 and 18:2n-6 were the dominant fatty acids amongst the saturates, monoenes and PUFA, respectively, and accounted for 80.8&ndash;88.7% of all identified fatty acids (23) in muscle of Murray cod. The study showed that Murray cod could be cultured successfully on a diet (DU2) containing 20% soybean meal without compromising growth and/or carcass quality. Differences in the proximate composition and fatty acid composition of muscle of wild and farmed Murray cod were observed, the most obvious being in the latter. Wild Murray cod had significantly less (P&lt;0.05) saturates (192.6&plusmn;1.84 vs. 266.3&plusmn;3.51), monoenes (156.5&plusmn;8.7 vs. 207.6&plusmn;6.19), n-3 (145.2&plusmn;5.24 vs. 261.8&plusmn;3.2) but higher n-6 (144.3&plusmn;2.73 vs. 48.3&plusmn;1.38) in muscle (all values are in &mu;g mg lipid&minus;1) than in farmed fish. Wild fish also had a much lower n-3 to n-6 ratio (1.0&plusmn;0.03 vs. 5.4&plusmn;0.09).<br /