Zhang Yangdong, Xu Qingbiao, Hou Jinxiu, Huang Guoxin, Zhao Shengguo, Zheng Nan, Wang Jiaqi
State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China.
Ministry of Agriculture Milk Risk Assessment Laboratory, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
J Sci Food Agric. 2022 May;102(7):2676-2685. doi: 10.1002/jsfa.11607. Epub 2021 Nov 2.
Milk microRNA (miRNA) with bioactivity is beneficial for human health. However, the effect of heat treatment on miRNA in milk is still not clear. In this study, the miRNAs in raw (RM), pasteurized (PM) and ultra-high-temperature (UHT) milk (UM) from the same batch were extracted, sequenced and analyzed.
The results showed that there was a significant difference in miRNAs between RM and UM, but not between RM and PM. The total read counts of milk miRNAs were significantly decreased by heat treatment, with the least counts in UM (P < 0.05). The average length and GC percentage of miRNAs were significantly reduced by heat treatment (P < 0.05), while there was no significant difference in these terms between RM and PM. The content of miRNAs was verified by qPCR, finding that miR-17-5p, miR-25, miR-27b and miR-9-5p were significantly reduced in UM (P < 0.05) but not significantly affected in PM (except miR-27b). In addition, the targeting gene ontology enrichment functions of the different presented miRNAs were mostly enriched in biological process, cellular component and molecular function. The top 20 enriched miRNAs with different levels in heat-treated milk were identified by the Kyoto Encyclopedia of Genes and Genomes enrichment analysis. Interestingly, most of the functions of these miRNA targeting genes are involved in cancer or inflammation activity.
This study revealed that the bioactive miRNA in RM was lost after UHT treatment but not in pasteurized treatment. © 2021 Society of Chemical Industry.
具有生物活性的牛奶微小RNA（miRNA）对人体健康有益。然而，热处理对牛奶中miRNA的影响仍不清楚。在本研究中，提取、测序并分析了同一批次的生乳（RM）、巴氏杀菌乳（PM）和超高温灭菌乳（UM）中的miRNA。
结果表明，RM和UM之间的miRNA存在显著差异，但RM和PM之间没有。热处理显著降低了牛奶miRNA的总读数，UM中的读数最少（P < 0.05）。热处理显著降低了miRNA的平均长度和GC含量（P < 0.05），而RM和PM之间在这些方面没有显著差异。通过qPCR验证了miRNA的含量，发现UM中miR-17-5p、miR-25、miR-27b和miR-9-5p显著降低（P < 0.05），而PM中没有显著影响（miR-27b除外）。此外，不同呈现的miRNA的靶向基因本体富集功能大多富集在生物过程、细胞成分和分子功能中。通过京都基因与基因组百科全书富集分析确定了热处理牛奶中不同水平的前20种富集miRNA。有趣的是，这些miRNA靶向基因的大多数功能都与癌症或炎症活动有关。
本研究表明，RM中的生物活性miRNA在超高温处理后丧失，但在巴氏杀菌处理后没有。© 2021化学工业协会。
