Earth and Environmental Science Department, University of Milano Bicocca, Milan, Italy.
Department of Biotechnology and Bioscience, University of Milano Bicocca, Milan, Italy.
J Sci Food Agric. 2019 Aug 15;99(10):4571-4579. doi: 10.1002/jsfa.9696. Epub 2019 Apr 17.
Marine lipids are widely recognized as supplements beneficial to health in the human diet. Bluefin tuna, as most migrating fish, may have high and variable marine lipid contents in their tissues. The viscera of the specimens caught in the Mediterranean Sea are generally discarded. Only ovaries are (locally) used for artisanal seafood preparations.
A multi-analytical approach carried out using infrared (IR), nuclear magnetic resonance (NMR) and mass spectrometry (MS) revealed that the perigonadal fats usually discarded during bluefin tuna evisceration are characterized by a high relative abundance of polyunsaturated triacylglycerols (76.2% of dry mass), with docosahexaenoic (DHA, 22:6) and eicosapentaenoic (EPA, 20:5) acids preferentially located at the sn-2 position of the glycerol backbone. By contrast, in fats from the ovarian tissues, no wax esters and phospholipids were evidenced. Cholesterol was found in very low amounts (84 mg/100 g ovarian tissue). In vitro assays showed that this fatty material is rapidly hydrolyzed by lipase and is prone to auto-oxidation, especially if compared to the stable wax esters contained in the ovary.
The results show that the perigonadal fats of bluefin tuna, traditionally wasted after evisceration, may be an interesting source for the preparation of marine lipid supplements that do not require complex fractionation processes. © 2019 Society of Chemical Industry.
海洋脂质被广泛认为是有益于人类饮食健康的补充剂。蓝鳍金枪鱼作为大多数洄游鱼类，其组织中的海洋脂质含量可能很高且变化不定。在地中海捕获的标本的内脏通常被丢弃。只有卵巢（在当地）用于手工海鲜制品的制备。
使用红外（IR）、核磁共振（NMR）和质谱（MS）进行的多分析方法表明，在蓝鳍金枪鱼去脏过程中通常丢弃的性腺周围脂肪的特点是高度丰富的多不饱和三酰基甘油（占干重的 76.2%），二十二碳六烯酸（DHA，22:6）和二十碳五烯酸（EPA，20:5）优先位于甘油主链的 sn-2 位。相比之下，卵巢组织中的脂肪没有蜡酯和磷脂。胆固醇的含量非常低（每 100 克卵巢组织 84 毫克）。体外试验表明，这种脂肪物质很快被脂肪酶水解，并容易自动氧化，特别是与卵巢中含有的稳定蜡酯相比。
研究结果表明，传统上在去脏后被丢弃的蓝鳍金枪鱼性腺周围脂肪可能是制备海洋脂质补充剂的一个有趣来源，而不需要复杂的分馏过程。© 2019 化学工业协会。
