State Key Laboratory of Marine Food Processing & Safety Control, National Engineering Research Center of Seafood, Collaborative Innovation Center of Seafood Deep Processing, School of Food Science and Technology, Dalian Polytechnic University, Qinggongyuan 1, Ganjingzi District, Dalian, 116034, PR China.
Food Funct. 2024 Sep 30;15(19):10190-10199. doi: 10.1039/d4fo02659d.
Lipid oxidation profoundly impacts its digestibility, a topic that has been predominantly investigated in triglyceride (TAG)-based dietary lipids. However, there is a dearth of similar research on lipids with diverse classes, such as Antarctic krill oil (AKO), which encompasses a spectrum of lipids including glycerides and phospholipids. This study aimed to elucidate the influence of lipid oxidation on the digestibility of AKO through a simulated gastrointestinal digestion (SGID) model. Post-SGID, AKO exhibited oxidative changes, evidenced by an escalation in peroxide value, conjugated diene value, thiobarbituric acid reactive substances and Schiff base formation. Concurrently, the digestibility of oxidized AKO was found to be inferior to that of fresh AKO, as indicated by a diminished hydrolysis degree of TAGs and phosphatidylcholine (PC), along with a reduced release of free fatty acids. Furthermore, co-digestion with tea polyphenol palmitate was observed to mitigate the oxidation of AKO and the digestion of PC during the SGID, while exerting no significant impact on TAG digestion. Notably, the emulsification capacity of oxidized AKO in a simulated intestinal fluid (without pancreatin and phospholipase A) was also found to be inferior to that of its fresh counterpart. These findings suggest that lipid oxidation may adversely affect the emulsification capacity of AKO under simulated intestinal conditions, thereby leading to a decrement in digestibility.
脂质氧化会深刻影响其消化率，这是一个在基于甘油三酯（TAG）的膳食脂质中得到广泛研究的课题。然而，对于具有不同类别脂质的研究相对较少，例如南极磷虾油（AKO），它包含甘油酯和磷脂等多种脂质。本研究旨在通过模拟胃肠道消化（SGID）模型来阐明脂质氧化对 AKO 消化率的影响。经过 SGID 后，AKO 表现出氧化变化，这可以通过过氧化物值、共轭二烯值、硫代巴比妥酸反应物质和席夫碱形成的增加来证明。同时，氧化的 AKO 的消化率被发现低于新鲜 AKO，这表明 TAG 和磷脂酰胆碱（PC）的水解程度降低，游离脂肪酸的释放减少。此外，在 SGID 过程中，与茶多酚棕榈酸共消化被观察到可以减轻 AKO 的氧化和 PC 的消化，而对 TAG 消化没有显著影响。值得注意的是，在没有胰酶和磷脂酶 A 的模拟肠液中，氧化的 AKO 的乳化能力也被发现低于其新鲜对应物。这些发现表明，脂质氧化可能会在模拟肠道条件下对 AKO 的乳化能力产生不利影响，从而导致消化率降低。
