丁香有效部位对LDL中脂类、蛋白氧化修饰及光谱学变化的抑制

LDL氧化修饰是致动脉粥样硬化的关键性因素。其中，在氧化修饰过程中LDL所含脂类、蛋白及其光谱学性质均会受到影响。前期研究结果发现丁香对LDL氧化修饰具有很强的抑制作用。但是，丁香是否是通过抑制脂类及蛋白氧化来实现，以及丁香是否能抑制LDL氧化修饰后光谱学性质的改变，这些问题目前均不清楚。据此，运用紫外吸收光谱、荧光光谱等方法研究了丁香有效部位(effective fraction from clove，EFC)对LDL氧化修饰的抑制效果。研究结果表明，EFC能有效延缓脂质氧化过程中共轭二烯(CD)增殖及推后其达到最大值，并抑制胆固醇降解;也可抑制蛋白组分apoB100中Trp荧光猝灭及Lys氧化修饰和荧光光谱变化;同时也能抑制LDL中脂质与蛋白过氧化产物-脂褐素的生成;此外，该部位对LDL 氧化修饰过程中紫外-可见光谱学特征的改变也有影响。论文将为丁香抗AS功能食品研发提供参考。

The Antioxidant Inhibition of Clove Effective Fraction on Lipid,Protein and Spectra Variation of LDL

Oxidation of low density lipoprotein (LDL) has been considered as the critical factor which led to atherosclerosis (AS). Lipid and protein in LDL were oxidized to cause change of spectra during oxidation. Clove has been demonstrated to possess the strongest antioxidant capacity among 87 both medical and edible plants proclaimed by China. However, whether LDL oxidation is inhibited by clove? If so, whether it inhibits the oxidation of lipid and protein in LDL, and how does spectral characteristic of LDL change during oxidation when clove was added into LDL. Currently, these questions are still unclear. Therefore, the inhibition efficiency of the effective fraction from clove (EFC) on oxidation of LDL was studied by UV-Visible spectra and fluorescence spectra. The results indicated that EFC might effectively delay propagation of conjugated diene (CD) during LDL oxidation and postpone reaching maximum of its content. Likewise, it might inhibit cholesterol degradation, tryptophan (Trp) fluorescence quenching, lysine (Lys) residues from being modified, and lipofuscins from being generated in peroxidatic reaction among lipid and protein.Besides, EFC also might affect variation of UV-Visible spectra of LDL during oxidation. This study provides reference for future research and development of clove functional food inhibiting AS.