代谢组学和系统生物学研究要求数据丰富、重复性好,简单易行、浸提效率高的样品前处理方法是获得较好的试验结果的关键步骤。比较了不同浸提剂(甲醇、乙醇和高氯酸)和不同研磨方法(球磨机和研钵研磨)对茶树叶片品质成分的浸提效果,结果表明,70%乙醇和70%甲醇对茶鲜叶氨基酸的浸提效率显著高于无水甲醇和无水乙醇,而对鲜叶茶多酚的浸提效率以100%乙醇和70%乙醇最好;3 mol·L-1高氯酸对鲜叶氨基酸浸提效率最高,超过70%乙醇,但对茶多酚的浸提效率最低。优化出一种针对茶树鲜叶浸提的快速前处理方法(70%乙醇,球磨机研磨5 min)。对鲜叶经冷冻干燥和微波杀青处理后浸提的茶多酚和氨基酸含量进行了比较,发现冷冻干燥可以更好地保持茶树叶片中特征代谢产物成分。
Metabolomic and systems biology require the acquisition of reproducible, reliable and homogeneous biological data set, the efficient extraction method is the key step in getting the satisfactory results of investigation. The influence on the extracting effect of quality-related constituents in tea leaves was investigated on various extracting solvents(methanol, ethanol, HClO4) and various grind methods (ball grinder and mortar). Results showed that 70% ethanol and 70% methanol proved to be more suitable solvent for extracting the amino acids in fresh tea leaves compared with 100% methanol and 100% ethanol. For tea polyphenols, 100% ethanol and 70% ethanol showed the highest extraction efficiency. 3 mol·L-1 HClO4 showed obvious advantage over all other solvents for amino acids extraction in fresh tea leaves, however, it showed the lowest extraction efficiency in tea polyphenols extraction. The use of 70% ethanol and grinded by ball grinder for 5 min has been proved to be the most suitable method. In addition, the amino acids and tea polyphenols concentration in freeze-dried leaves and oven-dried leaves were compared, the results showed that freeze-dry process could retain more quality-related constituents in tea leaves.
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