Abstract：
The common presence of glycidyl esters (GEs) in refined vegetable oils has been a concern for food safety. The present study aimed to investigate the inhibitory effects of three carotenoids derived from Haematococcus pluvialis microalga on GE formation in both rice oil and a chemical model during heating. The addition of astaxanthin (AS), lutein (LU), and β-carotene (CA) at 0.6 mg/g in rice oil can reduce GE formation by 65.0%, 57.1%, and 57.5%, respectively, which are significantly higher than those achieved by common antioxidants such as l-ascorbyl palmitate (39.0%), α-tocopherol (18.5%), tert-butyl hydroquinone (42.7%), and quercetin (26.2%). UPLC-Q-TOF-MS/MS analysis showed that two new compounds, that is, propylene glycol monoester and diester of palmitic acid, were formed in the CA-added chemical model, which provided direct experimental evidence for the inhibition of antioxidants including AS, LU, and CA against GE formation not only by indirect antioxidative action but also by direct radical reactions to competitively prevent the formation of cyclic acyloxonium intermediates. Furthermore, it was interestingly found that only AS could react with the GEs. The adduct of AS with GEs, astaxanthin-3-O-propanetriol esters, was preliminarily identified using Q-TOF-MS/MS in the heated AS-GE model, suggesting that reacting with GEs might represent another distinct mechanism of AS to eliminate GEs.
摘要：
缩水甘油酯（GE）在精制植物油中的常见存在一直是食品安全的问题。本研究旨在研究三种源自雨生红球藻微藻的类胡萝卜素对大米油和加热过程中化学模型中GE形成的抑制作用。虾青素（AS）的添加，叶黄素(LU),和β-胡萝卜素(CA)在0.6毫克/克的米油可以减少65.0%的GE形成,57.1%,57.5%,分别,显着高于普通抗氧化剂，如l-抗坏血酸棕榈酸酯（39.0％），α-生育酚（18.5%），叔丁基对苯二酚(42.7%),槲皮素（26.2%）。UPLC-Q-TOF-MS/MS分析表明,也就是说,棕榈酸的丙二醇单酯和二酯，在添加CA的化学模型中形成，这为抑制包括AS在内的抗氧化剂提供了直接的实验证据，LU,和CA对抗GE的形成不仅通过间接抗氧化作用，而且通过直接自由基反应竞争性地防止环状酰氧基鎓中间体的形成。此外，有趣的是，只有AS才能与GEs做出反应。AS与GEs的加合物，虾青素-3-O-丙三醇酯，在加热的AS-GE模型中使用Q-TOF-MS/MS进行了初步鉴定，这表明与GEs反应可能代表了AS消除GEs的另一种独特机制。
