Department of Physiology, Faculty of Medicine, Canadian Centre for Agri-food Research in Health and Medicine and Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, University of Manitoba, Winnipeg, Canada R2H 2A6.
J Chromatogr B Analyt Technol Biomed Life Sci. 2013 Jan 1;912:24-32. doi: 10.1016/j.jchromb.2012.10.030. Epub 2012 Nov 1.
Dietary interventions involving foods that are enriched in lignans, such as flaxseed, are drawing attention due to their beneficial protective effects in various diseases and human conditions. Accurate quantitation of key lignan metabolites such as enterodiol (END) and enterolactone (ENL) is necessary in order to identify factors that may influence overall bioavailability. Here we describe the validation of a novel supported liquid extraction (SLE) method for isolation of plasma enterolignans, END and ENL, using (2)H(6)-labeled isotopes with gas chromatography-mass spectrometry in micro selected ion storage (GC/MS-μSIS) mode. Following enzymatic hydrolysis and SLE extraction with 70:30 diethyl ether:ethyl acetate, enterolignans were rapidly separated within 8min. SLE in combination with GC/MS-μSIS gave high recoveries of 96.4% and 96.0% for END and ENL. Intra-assay precision ranged from 2.5 to 5.9% for both compounds whereas the inter-assay precision was 2.6-6.9%. SLE was also directly compared to liquid liquid extraction (LLE). Both techniques offered high precision and accuracy, however, SLE consistently enabled successful analyte extractions and derivatizations, unlike LLE, which had an ∼4% failure rate. SLE was also tested in a study where dietary milled flaxseed supplementation (30g/day for 1month) and enterolignan bioavailability was examined in a healthy, human population (n=10). Plasma total enterolignan levels significantly increased (P=0.002) at 4weeks relative to baseline. Average concentrations for END and ENL were 209nM and 304nM, respectively.
涉及富含木脂素的食物的饮食干预，如亚麻籽，由于其在各种疾病和人类状况中的有益保护作用而引起关注。为了确定可能影响整体生物利用度的因素，需要准确定量关键木脂素代谢物，如肠二醇（END）和肠内酯（ENL）。在这里，我们描述了一种新型支持液提取（SLE）方法的验证，用于使用（2）H（6）-标记同位素通过微选择离子存储（GC/MS-μSIS）模式分离血浆肠内木脂素、END 和 ENL。在酶水解和 70:30 乙醚：乙酸乙酯的 SLE 提取后，肠内木脂素在 8 分钟内迅速分离。SLE 与 GC/MS-μSIS 结合使用，可使 END 和 ENL 的回收率分别达到 96.4%和 96.0%。两种化合物的日内精密度范围为 2.5%至 5.9%，而日间精密度为 2.6%至 6.9%。SLE 也直接与液液萃取（LLE）进行了比较。这两种技术都具有高精度和准确性，但是与 LLE 不同，SLE 始终能够成功进行分析物提取和衍生化，LLE 的失败率约为 4%。SLE 还在一项研究中进行了测试，该研究中在健康人群（n=10）中检查了食用磨碎的亚麻籽补充剂（30g/天，持续 1 个月）和肠内木脂素生物利用度。与基线相比，4 周时血浆总肠内木脂素水平显著增加（P=0.002）。END 和 ENL 的平均浓度分别为 209nM 和 304nM。
