College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, People's Republic of China.
Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture, Shanghai 201306, People's Republic of China.
J Agric Food Chem. 2021 Mar 24;69(11):3479-3488. doi: 10.1021/acs.jafc.1c00046. Epub 2021 Mar 11.
In this research, we studied the inhibitory mechanism of quercetin, one popular phenolic compound, against aldehyde formation in thermally treated soybean oil. It was found that quercetin reduced unsaturated aldehyde formation significantly, with the inhibitory effect decreased with the extension of the heating time. Meanwhile, quercetin had minimum effects on the fatty acid profile compared to untreated samples. Some new phenolic derivatives were formed in thermally treated soybean oil with quercetin, further analyzed by liquid chromatography-tandem mass spectrometry, and compared to newly synthesized derivatives (characterized by mass spectrometry and nuclear magnetic resonance spectroscopy). On the basis of their chemical structures, we proposed that quercetin reacted with 13-oxo-octadecadienoic acid, 10-oxo-hexadecenoic acid, and 10-oxo-octadecenoic acid formed from peroxidation of linoleic acid, palmitoleic acid, and oleic acid, respectively, to inhibit aldehyde formation. In addition, newly formed quercetin-3--hexanoate, quercetin-3--heptanoate, and quercetin-3--nonanoate showed weaker 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation scavenging activity and weaker antioxidant activity in soybean oil, which explained the decreased inhibitory activity of quercetin against aldehyde formation during heat treatment. More interesting, quercetin-3--hexanoate showed improved cellular antioxidant activity compared to the parent quercetin. Overall, quercetin inhibited the formation of lipid oxidation products in thermally treated soybean oil by reacting with early intermediates in the lipid oxidation reaction, and quercetin derivatives formed in the process could be with enhanced cellular antioxidant activity. Our results provide novel insight into the inhibitory mechanism of quercetin against the formation of lipid oxidation products.
在这项研究中，我们研究了槲皮素（一种常见的酚类化合物）对热处理大豆油中醛形成的抑制机制。结果发现，槲皮素显著减少了不饱和醛的形成，随着加热时间的延长，抑制效果降低。同时，与未处理的样品相比，槲皮素对脂肪酸组成的影响最小。用液相色谱-串联质谱法进一步分析了含有槲皮素的热处理大豆油中形成的一些新的酚类衍生物，并与新合成的衍生物（通过质谱和核磁共振波谱法进行了表征）进行了比较。根据它们的化学结构，我们提出槲皮素分别与 13-氧代-十八碳二烯酸、10-氧代-十六碳烯酸和 10-氧代-十八碳烯酸反应，这些酸是由亚油酸、棕榈油酸和油酸的过氧化形成的，以抑制醛的形成。此外，新形成的槲皮素-3--己酸酯、槲皮素-3--庚酸酯和槲皮素-3--壬酸酯在大豆油中的 2,2-二苯基-1-苦基肼和 2,2'-联氮-双（3-乙基苯并噻唑啉-6-磺酸）二铵盐自由基阳离子清除活性以及抗氧化活性较弱，这解释了在热处理过程中槲皮素对醛形成的抑制活性降低。更有趣的是，槲皮素-3--己酸酯的细胞抗氧化活性比母体槲皮素有所提高。总的来说，槲皮素通过与脂质氧化反应中的早期中间体反应，抑制热处理大豆油中脂质氧化产物的形成，并且在该过程中形成的槲皮素衍生物可能具有增强的细胞抗氧化活性。我们的研究结果为槲皮素抑制脂质氧化产物形成的抑制机制提供了新的见解。
