沙葱及其提取物对舍饲肉羊肾周脂肪膻味物质代谢组特征的影响

本试验旨在探究不同膻味水平舍饲肉羊肾周脂肪代谢组学特征。试验分为4组,每组15只小尾寒羊羔羊,其中各试验组分别饲喂沙葱粉（AMR）、沙葱水提物（AWE）及沙葱醇提物（AFE）,对照组（CK）饲喂基础饲粮。试验结束后从各组中随机选择6只羊屠宰,采集背部皮下脂肪、尾部脂肪、肾周脂肪和大网膜脂肪样品,检测4-烷基支链脂肪酸（BCFA）的沉积量,并以此为依据筛选极高膻味水平样品和极低膻味水平样品。采用LC-MS的方法,探究不同膻味水平舍饲肉羊肾周脂肪代谢组学特征。结果表明：沙葱及其提取物能够改善除尾部脂肪外其它部位脂肪组织中（肾周脂肪、背部皮下脂肪和大网膜脂肪）3种支链脂肪酸,且肾周脂肪最为敏感,其中沙葱醇提物对降低肾周脂肪中3种支链脂肪酸的沉积量效果最佳（MOA P<0.001;MNA P=0.044;EOA P<0.001）。代谢组学研究发现,组氨酸代谢通路、甘油磷脂代谢通路、精氨酸和脯氨酸代谢通路及亚油酸代谢通路及其相关代谢产物可能与膻味相关物质的合成有关。综上所述,沙葱醇提物可能通过影响舍饲肉羊机体脂肪酸及氨基酸代谢通路,调控相关代谢产物的合成,进而影响4-烷基支链脂肪酸的合成,从而改善羊肉膻味。

Effect of Allium mongolicum Regel and Its Extract on the Metabolomic Characteristics of Perirenal Adipose Tissue Typical Odor and Flavor Substances in Captive Meat Sheep

This experiment aimed to investigate the characterization of perirenal adipose tissue metabolomics of captive meat sheep with different typical odor and flavor levels. The experiment was divided into four groups with 15 lambs each, of which each test group was fed with Allium mongolicum Regel powder(AMR), Allium mongolicum Regel water extract (AWE), and Allium mongolicum Regel ethanol extract (AFE), respectively, and the control group (CK) was fed with the basal diet. At the end of the experiment, six sheep were randomly selected from each group for slaughter, and samples of perirenal adipose tissue (PF), tail adipose tissue (TF), dorsal subcutaneous adipose tissue (DF), and omental adipose tissue (GF) were collected to measure the deposition of 4-alkyl branched-chain fatty acids (BCFA), which were used as a basis for screening samples with extremely high and low odor and flavor. LC-MS was used to investigate the characterization of perirenal adipose tissue metabolomics of captive meat sheep with different typical odor and flavor levels. The results showed that, the addition of AMR, AWE, or AFE to the sheep diet reduced the content of 3 kinds of BCFA in the DF, PF, and GF to different degrees except for TF, and AFE had a stronger influence in terms of its effect on PF (MOA P<0.001; MNA P=0.044; EOA P<0.001, respectively). Metabolomics revealed that the histidine metabolism, glycerophospholipid metabolism, arginine and proline metabolism, linoleic acid metabolism, and their related metabolites might be related to the synthesis of typical odor and flavor-related substances. In conclusion, AFE may improve the typical odor and flavor of lamb by modulating the fatty acid and amino acid metabolic pathways in the body of captive meat sheep, which further affects the synthesis of 4-alkyl branched-chain fatty acids.