5种不同畜禽肉中脂肪酸组成和脂质差异分析

Analysis of fatty acid composition and lipid difference in 5 kinds of livestock and poultry meat

中文关键词:  畜禽肉  脂肪酸  脂质  超高效液相色谱-四极杆飞行时间质谱法

英文关键词:livestock and poultry meat  fatty acid  lipids  ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry

中文摘要:

      目的 基于超高效液相色谱-四极杆飞行时间质谱法(ultra performance liquid chromatography- quadrupole time-of-flight mass spectrometry, UPLC-QTOF/MS)和脂质组学分析技术分析不同畜禽肉中脂肪酸和脂质组成差异。方法 样品经脂肪提取、皂化和萃取后采用C8柱分离, 以水+甲醇(9:1, V:V)和乙腈+甲醇+异丙醇(2:3:5, V:V:V)为流动相进行梯度洗脱, 经UPLC-QTOF/MS定性分析, 总脂肪酸外标法定量, 脂质面积百分比半定量, 并结合主成分分析(principal component analysis, PCA)和偏最小二乘法判别(partial least squares discriminant analysis, PLS-DA)等统计学手段, 实现脂质差异分析。结果 该方法可对38种脂肪酸进行准确定性与定量; 检出限范围在0.050~1.000 μg/g, 定量限范围在0.125~2.500 μg/g, 线性相关系数(r2)均大于0.99; 以亚油酸-13C18为模型进行准确性评价, 加标回收率范围为93%~104%, 相对标准偏差范围为2.6%~3.9%。正、负模式下分别测得355、192种化合物, 共筛选出42种差异性化合物, 主要为磷脂酰胆碱和游离脂肪酸, 差异脂肪酸主要为棕榈酸、硬脂酸、油酸、亚油酸和花生四烯酸。结论 本研究中脂肪酸测定方法操作简便、分析时间短, 适用于大规模畜禽肉类总脂肪酸的定性定量测定。不同畜禽肉中主要差异脂质集中于棕榈酸、油酸、花生四烯酸等脂肪酸所构成的磷脂酰胆碱类和脂肪酸类脂质。

英文摘要:

      Objective To analyze the difference of the total fatty acids and lipids in different livestock and poultry meats based on ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) and lipidomic techniques. Methods The samples were gradient-eluted and separated on a C8 column after lipid extraction and saponification. The mobile phase were water+methanol (9:1, V:V) and acetonitrile+methanol+isopropanol (2:3:5, V:V:V). The lipids and fatty acids were qualified through UPLC-QTOF. The lipids were semi-quantified using area percentage method while the total fatty acids were quantified by external standard method. Statistical tools including principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used to analyze lipid differences. Results Totally 38 kinds of fatty acids could be accurately qualified and quantified in this method. The limits of detection were in the range of 0.050-1.000 μg/g, and the limits of quantification were in the range of 0.125-2.500 μg/g. The linear coefficients (r2) were greater than 0.99. Using linoleic acid-13C18 as the model compound, the recoveries at 3 spiking levels were in the ranges of 93%?104%, and the relative standard deviations were in the ranges of 2.6%?3.9%. The 355 and 192 compounds were detected in the positive and negative modes, respectively. A total of 42 differential compounds were screened, mainly phosphatidylcholine and free fatty acids. The differential fatty acids were mainly palmitic acid, stearic acid, oleic acid, linoleic acid and arachidonic acid. Conclusion The analysis method in this study is easy to operate, less time-consuming and suitable for the large-scale analysis of total fatty acids and the lipidomic analysis in livestock and poultry meat. The main difference lipids in different livestock and poultry meats are mainly phosphatidylcholines and fatty acid lipids composed of fatty acids such as palmitic acid, oleic acid and arachidonic acid.