三七稳定同位素指纹的环境响应机制及产地溯源地理尺度研究

Panax notginseng is a special authentic Chinese herb in yunnan province, which originated from Wenshan has been protected by the national geographical indication. With the aggravation of continuous cropping disorder, the areas of Panax notginseng cultivation region gradually expand outward. Therefore, it is necessary to carry out origin traceability and authentication for the sustainable development of the Panax notginseng industry. The stable isotope fingerprint in plants is fractionated by factors such as ecological factors, geological background and regional pollution, and has significant regional characteristics. Our previous studies have shown that the dominant ecological factors affecting the stable carbon isotope ratio in different organs of Panax notginseng have both commonness and difference. The discriminating models were established based on C,H, O, N stable isotopic fingerprints of 44 taproot of Panax notoginseng according to 3 main producing area, by which 84.09% correct classification obtained. Adopting multi-discipline theories and methods of isotope ecology, isotope geochemistry, chemo-metrics, and resource of medical plants, etc., this project will systematically and deeply study the response mechanism of stable isotopic fractionation influenced by ecological and environmental factors, establish isotopic ratio predicting models based on dominant ecological factors, explore the geographic scale of the stable isotope fingerprint in the origin of Panax notoginseng provenances, screen and establish technological index systems and discrimination models of different organs and geographic scales for origin traceability of Panax notoginseng, develop techniques of geographical origin traceability and authenticity of Panax notoginseng based on stable multi-isotopic fingerprints. The objective is to provide technical support for the origin of traditional Chinese medicinal materials.

三七是云南特色道地中药材，文山三七获国家地理标志保护，随着连作障碍的加重，三七产区逐渐向外扩展。因此，三七产地溯源和确证对三七产业的可持续发展十分必要。植物体内稳定同位素指纹受生态因子、地质背景、区域污染等因素影响而发生分馏，具有显著的地域特征。前期研究表明，影响三七不同器官稳定碳同位素比率的主导生态因子有共性，也有差异。基于3个主产区44个三七块根样品C、H、O、N同位素指纹建立的产地判别模型，判别正确率为84.09%。本项目采用同位素生态学、同位素地球化学、化学计量学、药用植物资源学等多学科的理论和方法，深入研究三七不同器官稳定同位素分馏的环境响应机制并建立预测模型；探索稳定同位素指纹在三七产地溯源中的地理尺度，筛选和建立基于稳定同位素指纹的三七不同器官和地理尺度的产地溯源技术指标体系和判别模型；形成三七稳定同位素指纹产地溯源及确证技术，为道地中药材产地溯源提供技术支撑。

三七是云南特色道地中药材，文山三七获国家地理标志保护，由于三七严重的连作障碍，三七产区逐渐向外扩展。稳定同位素指纹具有显著的地域特征，三七药材皂苷组分含量是衡量其品质和道地性的重要指标。通过相关、通径、逐步回归和决策分析等的逐层剖析，研究了地理气候因子、灌溉水δD、δO、土壤理化性质和肥力、器官内营养元素含量与三七茎叶、剪口、主根δD、δO、δC、δN的数量关系。筛选出了影响三七茎叶、剪口、主根稳定同位素δD、δO、δC、δN指纹的主要生态因子，并明确了各稳定同位素指标是否具有地域特征。以地域差异和年际稳定性，且地域对其变异影响最大作为溯源指标筛选的原则，主根为Rg1、Rb1、Rd、δO、δC、87/86Sr，剪口为Rg1、Rb1、δO、δC、δN、87/86Sr。建立了不同地理尺度的三七主根和剪口的产地溯源判别模型，并对三七样品进行多类逐步判别分析。省际三七样本可以正确区分，但在省际气候条件相似边界区域，也存在误判的可能；对州市际和县际的三七样本，按行政区判别正确率较低，按地理气候区可显著提高判别正确率，基本可满足三七药材产地判别的要求；三七主根和剪口判别效果和规律基本一致。利用C、H、O稳定同位素指纹特征建立春七与冬七判别模型，判别正确率达100%。利用3年春七主根稳定同位素指纹建立判别函数，对三七企业原料及产品进行产地判别，判别正确率达84.09%。研究结果可丰富稳定同位素产地溯源理论并拓展其应用领域，将为三七道地性研究和地理标志产品保护、国际贸易等提供科学依据。