柑橘果实成熟过程中氨基酸、维生素E和脂质的动态分析

为评价柑橘的抗氧化能力，利用GC-MS、UPLC和LC-MS/MS分别检测了6个柑橘品种果实在成熟过程中三类代谢物的相对含量。结果显示，柑橘果实以积累丝氨酸、脯氨酸和天冬氨酸为主，苏氨酸在柑橘青果时期的积累尤为丰富，且青果时期本地早橘汁胞中9种氨基酸的总含量最高；对维生素E而言，α-生育酚是柑橘中的主要异构形式，在成熟期柑橘的有色层中积累丰富；同时，柑橘不积累δ-生育酚且γ-生育酚只在柑橘有色层中积累；共鉴定到的8大类176种脂质，在柑橘果实中呈现出明显的时空分布特征，且卵磷脂为柑橘的主要脂质形式。通过柑橘果实中三类物质含量间的相关性分析发现，部分氨基酸与脂质存在高度正相关。

Analyzing dynamics of amino acid， vitamin E and lipids during fruit ripening in Citrus

Amino acids， vitamin E and lipids are three classes of metabolites with antioxidant activity. GC-MS， UPLC， and LC-MS/MS were used to detect the relative content of three types of metabolites in the fruits of six Citrus varieties during the ripening process to analyze the dynamic changes of amino acids， vitamin E， and lipids during the ripening process of citrus fruits and evaluate the antioxidant activity of citrus. The results showed that citrus fruits mainly accumulated serine， proline， and aspartic acid， while threonine was particularly abundant during the green fruit stage of citrus. The total content of nine amino acids in green pulp of C. chuana ‘Bendizao’ （BDZ） during the green fruit stage was the highest. For vitamin E， α- tocopherol is the main isomeric form in citrus， which accumulates abundantly in mature colored pericarp. Additionally， citrus fruits did not accumulate δ- tocopherol， and γ- tocopherol only accumulated in the colored pericarp of citrus. A total of 8 major categories （176 species） of lipids were identified and showed significant characteristics of spatiotemporal distribution in citrus fruits， with phosphatidylcholine being the main form of lipids in citrus. It was found that some amino acids are highly positively correlated with lipids through correlation analysis of the content of three types of metabolites in citrus fruits. It will have a guiding significance for the improvement of quality in citrus varieties.