目的 基于双进样液相色谱技术分析不同产地龙眼肉药材中3种可溶性糖和7种有机酸含量差异，为龙眼肉的质量控制及风味评价提供科学依据。方法 收集5个产地共51批次龙眼肉样本，利用双进样液相色谱仪同步运行检测，可溶性糖（果糖、葡萄糖、蔗糖）以乙腈-水（87∶13）为流动相等度洗脱，采用蒸发光散射检测器（ELSD）检测；有机酸（酒石酸、苹果酸、抗坏血酸、乳酸、柠檬酸、琥珀酸、富马酸）以甲醇-水（0.1%磷酸）梯度洗脱，采用光电二极管阵列检测器（PDA）检测。含量测定结果结合主成分分析（PCA）、偏最小二乘法-判别分析（PLS-DA）、聚类分析（HCA）和灰色关联度分析（GRA），综合评价不同产地龙眼肉的质量及风味。结果 3种可溶性糖的含量上存在显著差异，其中蔗糖平均含量（47.38 mg·g^-1）显著高于葡萄糖（10.49 mg·g^-1）和果糖（14.88 mg·g^-1），是区分不同批次龙眼肉的差异性成分，可作为龙眼肉质量控制指标，建议将其含量限度设定为不低于31.73 mg·g^-1；7种有机酸中，琥珀酸（45.78 mg·g^-1）和乳酸（44.18 mg·g^-1）平均含量显著高于其他有机酸，是区分不同批次龙眼肉的差异性成分，建议将琥珀酸和乳酸总含量限度设定为不低于56.15 mg·g^-1。GRA表明，中国广西、中国广东、中国福建3个地区来源的龙眼肉相对关联度（R_i）较大，质量较优；基于糖酸特征，将不同批次的龙眼肉分为6种风味，来自中国广西、中国广东和中国福建，呈现较好的甜酸平衡性，具有广泛的适应性。结论 蔗糖、琥珀酸和乳酸是影响龙眼肉品质的关键成分。中国广西、中国广东、中国福建样本品质优于泰国、越南样本：中国广西样本甜味突出，中国广东与中国福建样本甜酸更平衡，综合各项指标，中国广西龙眼肉综合品质更优。

Objective To analyze the differences in the contents of three soluble sugars and seven organic acids in Longan Arillus (Dimocarpus longan Lour.) from different origins by using dual-injection liquid chromatography technology, and to provide a scientific basis for the quality control and flavor evaluation of Longan Arillus.Methods A total of 51 batches of Longan Arillus samples from five origins were collected. The dual-injection liquid chromatography system was used for simultaneous detection. The three soluble sugars (fructose, glucose, and sucrose) were eluted isostatically with acetonitrile-water (87∶13) and detected by evaporative light scattering detector (ELSD). The seven organic acids (tartaric acid, malic acid, ascorbic acid, lactic acid, citric acid, succinic acid, and fumaric acid) were eluted with a gradient of methanol-water (0.1% phosphoric acid) and detected by photodiode array detector (PDA). The content determination results were combined with principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), hierarchical cluster analysis (HCA), and grey relational analysis (GRA) to comprehensively evaluate the quality and flavor of Longan Arillus from different origins.Results There were significant differences in the contents of the three soluble sugars. The average content of sucrose (47.38 mg·g^-1) was significantly higher than that of glucose (10.49 mg·g^-1) and fructose (14.88 mg·g^-1), and it was a differential component for distinguishing different batches of Longan Arillus, which could be used as a quality control index. It is recommended that the content limit be set at no less than 31.73 mg·g^-1. Among the seven organic acids, the average contents of succinic acid (45.78 mg·g^-1) and lactic acid (44.18 mg·g^-1) were significantly higher than those of other organic acids, and they were differential components for distinguishing different batches of Longan Arillus. It is recommended that the total content limit of succinic acid and lactic acid be set at no less than 56.15 mg·g^-1. GRA indicated that the Longan Arillus from Guangxi, Guangdong and Fujian in China had larger relative correlation degree (Ri) values and better quality. Based on the sugar-acid characteristics, the Longan Arillus samples were classified into six flavors. The samples from Guangxi, Guangdong and Fujian in China showed a better balance of sweetness and acidity and had wide adaptability.Conclusion Sucrose, succinic acid and lactic acid are the key components that affect the quality of Longan Arillus. The samples from Guangxi, Guangdong and Fujian in China have better quality than those from Thailand and Vietnam. The samples from Guangxi in China, have a prominent sweetness, while the samples from Guangdong and Fujian in China, have a more balanced sweetness and acidity. Based on all the indicators, the comprehensive quality of Longan Arillus from Guangxi in China is better.

R286.02

国家自然科学基金资助项目（82174209）