摘要
本研究以宁夏滩羊脂质为对象,基于OmicsBean组学数据整合分析云平台,分析气相色谱-质谱、液相色谱-质谱技术对冷鲜贮藏12 d的滩羊肉中可检测的全部脂肪差异代谢的变化过程。结果表明:代谢通路的种类呈先增加后减少趋势;与风味物质前体油酸、棕榈酸、硬脂酸等相关的代谢通路在0~4 d内无差异;4~8 d内,脂肪酸生物合成通路(P=6.65×10^-3)、促性腺激素释放激素(gonadortopin-releasing hormone,GnRH)信号通路(P=4.67×10^-2)差异显著,不饱和脂肪酸的生物合成通路也由0~4 d的差异不显著(P=3.24×10^-1)变为差异显著(P=5.87×105,8 d后脂肪酸生物合成通路、GnRH信号通路无差异,不饱和脂肪酸的生物合成通路差异不显著(P=1.57×10^-1);在贮藏初期,脂肪酸合成通路并未表现出差异,但有关棕榈酸等脂肪酸合成的前体短碳链化合物的相对含量有所变化,如3-羟基丁酸、3-氧代十六烷酸相对含量在0~4 d内差异显著;4~8 d,通路中有关棕榈酸分解、脂肪酸β氧化路径开启,此时棕榈酸的相对含量显著下降。脂肪酸生物合成通路开启是因多种氧代酰基酶、脂肪酸合成酶及乙酰辅酶A的激活,这些酶在0~4℃下0~4 d内催化底物生成3-羟基丁酸、3-氧代十六烷酸等形成棕榈酸的前体物质。说明宰后肌体处于缺氧环境下,代谢并未立即停止,且细胞仍有维持其能量处于正常水平的趋势,随着冷鲜贮藏时间的延长,肌体内的能量代谢通路更替供能,在代谢过程中,如油酸、硬脂酸、棕榈酸等风味前体物质的相对含量也发生了相应的变化。
The dynamic evolution of lipid metabolism in intramuscular fat of Ningxia Tan sheep during chilled storage for 12 days was investigated by combined use of gas chromatography-mass spectrometry(GC-MS)and liquid chromatographymass spectrometry(LC-MS)with the OmicsBean cloud platform.The results showed that the types of metabolism pathways increased at the beginning of storage,and then decreased.The metabolism pathways related to the flavor precursors oleic acid,palmitic acid and stearic acid were not different from day 0 to day 4,while the fatty acid biosynthesis pathways(P=6.65×10^-3<0.05)and the gonadotropin-releasing hormone(GnRH)signaling pathway(P=4.67×10^-2<0.05)were significantly different from day 4 to day 8;the biosynthesis pathways of unsaturated fatty acids pathway significantly differed from day 4 to day 8(P=5.87×10^-5)but not from day 0 to day 4(P=3.24×10^-1).From day 8 onward,the fatty acid biosynthesis pathways and the GnRH signaling pathway were not different,and the biosynthesis pathways of unsaturated fatty acids were not significantly different(P=1.57×10^-1).At the early stage of storage,no difference in the biosynthesis pathways of fatty acids was observed,but the relative contents of short carbon chain compounds as precursors for the biosynthesis of palmitic acid such as 3-hydroxybutyric acid and 3-oxohexadecanoic acid.Their relative contents were significantly different from day 0 to day 4;from day 4 to day 8,the palmitic acid decomposition and fatty acidβoxidation pathways were activated,and consequently,the relative content of palmitic acid decreased significantly.The initiation of the fatty acid biosynthesis pathways could be ascribed to the activation of a variety of oxoylases,fatty acid synthases and acetyl-CoA.These enzymes catalyzed the formation of 3-hydroxybutyrate and 3-oxohexadecanoic acid as precursors for the formation of palmitic acid during the first 4 days of storage at 0–4℃.Therefore,it seems that metabolism does not stop immediately postmortem despite oxygen deficiency,and cells are still able to maintain their normal energy level.As the chilled storage time prolongs,the energy metabolism pathways in the body alternately work for energy supply.During the metabolic process,the relative contents of flavor precursors such as oleic acid,stearic acid,and palmitic acid change accordingly.
作者
苑昱东
李子欣
罗瑞明
剧柠
尤丽琴
YUAN Yudong;LI Zixin;LUO Ruiming;JU Ning;YOU Liqin(School of Agriculture,Ningxia University,Yinchuan 750021,China)
出处
《食品科学》
EI
CAS
CSCD
北大核心
2020年第7期171-176,共6页
Food Science
基金
国家自然科学基金地区科学基金项目(31860427)。
关键词
滩羊
宰后
脂肪
代谢通路
通路转换
Tan sheep
postmortem
fat
metabolic pathway
pathway conversion