基于光谱学技术对丁香油与乙酸乙酯相抑制LDL非酶糖基化、氧化修饰能力的比较

The Comparison of Inhibition on LDL Non-Enzymatic Glycosylation and Oxidation between Ethyl Acetate Extracts of Clove and Clove Bud Oil Based on Spectroscopy Technology

低密度脂蛋白(LDL)非酶糖基化和氧化修饰均是导致动脉粥样硬化(AS)的关键因素。前人发现,丁香可有效抑制牛血清白蛋白(BSA)、高密度脂蛋白(HDL)糖基化修饰,丁香乙酸乙酯相(EAEC)和丁香油(CBO)均具有很强的抗氧化活性。为了确定丁香抑制LDL糖基化及氧化所对应的最有效成分,在前人研究基础上采用光谱学技术对EAEC和CBO抑制LDL糖基化及氧化功能进行了比较。首先建立LDL-葡萄糖糖基化孵育体系,通过测定糖基化早期、中期和末期产物及三维荧光光谱的变化比较CBO和EAEC抑制LDL糖基化修饰的效果。其次,建立LDL-CuSO4氧化孵育体系,通过测定荧光指标和三维荧光光谱、紫外可见波长扫描来比较两者抑制LDL氧化修饰效果。结果发现,EAEC和CBO对LDL糖基化修饰过程中产生的早期产物(Amadori产物)、中期产物(二羰基化合物)及终末期产物(戊糖素和AGEs)均具有很强的抑制效果,且EAEC的抑制效果均强于CBO;三维荧光光谱表征得到相同的结果。在LDL氧化修饰比较中,CBO对色氨酸(Trp)荧光猝灭、总荧光产物及脂褐素的生成、赖氨酸(Lys)修饰的抑制效果均显著强于非油成分的EAEC;三维荧光光谱表征也得到相同的结果;紫外、可见全波长扫描反映CBO比EAEC对共轭二烯(CD)生成及光谱红移的抑制效果更强。研究结果为后续锁定重点成分分离、纯化及研发丁香抗LDL糖基化及氧化功能食品提供参考。

Non-enzymatic glycosylation and oxidation of low density lipoprotein（LDL）both have been crucial factors leading to atherosclerosis（AS）.It was found in previous studies that clove had inhibitory effects on the glycosylationof bovine serum albumin（BSA）and high-density lipoprotein（HDL）,while ethyl acetate extracts of clove（EAEC）and clove bud oil（CBO）had strong antioxidant activity.In order to determine the most effective components of clove to inhibit LDL from glycosylation and oxidation,the comparisons of inhibition between EAEC and CBO on LDLglycosylation and oxidation were studied in this paper on the basis of the previous studies based on spectroscopy technology.The glycosylation incubation system of LDL-glucose was firstly established in this experiment.The inhibition between EAEC and CBO on LDL glycosylation was compared by the determination of the products during the early,middle and the end periods of glycosylation,and the spectra variations of the three-dimensional fluorescence.Secondly,LDL-CuSO4 as oxidation incubation system was established,and the inhibition between EAEC and CBO on LDL oxidation was compared by the determinations of fluorescence indicators and three-dimensional fluorescence spectroscopy,UV-Visible spectra.The results indicated that EAEC and CBO both have inhibition of the formation of Amadori,dicarbonyl compounds,AGEs and pentosidines which are products during the early,middle and the end period of LDL glycosylation respectively,and the inhibition effects of EAEC were stronger than those of CBO;three-dimensional fluorescence spectroscopy showed the same results as above.During LDL oxidation,the inhibition of CBO on tryptophan（Trp）fluorescence quenching,the formation of total fluorescence products and lipofuscin,lysine（Lys）modification were significantly better than those of EAEC;three-dimensional fluorescence spectroscopy showed the same results;CBO had stronger inhibitory effect than EAEC on conjugated diene（CD）generated and spectrum redshift in UV-Visible scanning spectra.This study provides a reference for further separation and purification of the key components,research anddevelopment of functional foods inhibiting LDL glycosylationand oxidation ofclove.