Quality variation and ecotype classification of Chinese herbal medicine are important scientific problems in Daodi herbal medicine research. The diversity of natural environmental conditions has led to form unique multi-Daodi, multi-product areas that produce particular Chinese herbal medicine. China is one of three big American ginseng (Panax quinquefolium L.) producing areas worldwide, with over 300 years of application and 40 years of cultivation history. Long-term production practice has led to the formation of three big advocate produce areas in China: Northeast province, Beijing and Shandong. P. quinquefolium L. grown under certain environmental conditions will develop long-term adaptations that will lead to more stable strains (different ecotypes). P. quinquefolium L., can vary greatly in quality; however, the ecological mechanisms causing this variation are still unclear. Root samples were collected from four-year-old cultivated P. quinquefolium L. plants in the three major genuine (Daodi) American ginseng-producing areas of Northeast province, Beijing and Shandong province, China. Ultra-performance liquid chromatography was used to analyze the contents of eight ginsenosides (Rg1, Re, Rb1, Rb2, Rb3, Rc, Rd, Rg2). Data for nine ecological factors, including temperature, moisture and sunlight, were obtained from the ecological database of Geographic Information System for Traditional Chinese Medicine. Soil samples from the sampling sites were collected. Effective boron and iron, available nitrogen and potassium, as well as other trace elements and soil nutrients, were determined by conventional soil physicochemical property assay methods. Analytical methods of biostatistics and numerical taxonomy were used to divide ecotypes of the three main Panax quinquefolium L. producing areas in China based on ginsenoside content, climate, soil and other ecological factors. To our knowledge, this is the first time that ecological division of P. quinquefolium L. producing areas in China has ever been conducted. The results show that there are two chemoecotypes of P. quinquefolium L. in China: ginsenoside Rb1-Re from outside Shanhaiguan, and ginsenoside Rg2-Rd from inside Shanhaiguan. Similarly, there are two types of climatic characteristics: inside Shanhaiguan (Beijing, Shandong) and outside Shanhaiguan (Northeast). This suggests that the formation and differentiation of chemoecotypes of P. quinquefolium L. is closely related to variability of the climatic and geographical environment. Additionally, ecological variation of the three main producing areas, characteristics of two climatic ecotypes, and soil characteristics are also discussed and summarized. These results provide experimental scientific evidence of the quality variation and ecological adaptation of P. quinquefolium L. from different producing areas. They also deepen our understanding of the biological nature of Daodi P. quinquefolium L. formation, and offer novel research models for other multi-origin, multi-Daodi Chinese herbal medicines ecotypes. In addition, the results demonstrate the critical need for improving quality, appropriate ecological regionalization and promoting industrialized development of P. quinquefolium L.

OBJECTIVE： To establish a method for content determination of indapamide （IDP）-β-cyclodextrin （β-CD） inclusion compound， optimize the preparation technology， carry out phase identification and in vivo release study of it. METHODS： UV spectrophotometry was used to determine the content of IDP in IDP-β-CD inclusion compound. IDP-β-CD inclusion compound was prepared by the solution-stirring method and the preparation technology was optimized by the orthogonal experiment using inclusion rate as index. The inclusion rate and drug-loading rate were compared between different drying methods. Phase identification of IDP-β-CD inclusion compound was verified by IR and DSC. The cumulative release rate of inclusion compound was tested by in vitro experiment. RESULTS： The linear range of concentration of IDP was 2.0-14.0 μg/mL （r＝0.999 7）. The quantitative limit and detection limit were 0.204， 0.067 μg/mL， respectively. RSDs of precision， stability and repeatability tests were all less than 2％. The recoveries range was 98.8％-101.8％（RSD＝1.10％，n＝6）. The optimum technology conditions were as follows the molar ratio of β-CD to IDP was 3 ∶ 1， the inclusion time was 3 h， and the stirring speed was 300 r/min. Average inclusion rate of IDP-β-CD inclusion compound was 72.81％. IR and DSC analysis showed that IDP and β-CD formed inclusion compound through physical interaction. After spray drying， the inclusion rate and drug-loading rate of IDP-β-CD inclusion compound were （60.96±0.25）％ and （4.18±0.12）％. After freeze-drying， the inclusion rate and drug-loading rate of IDP-β-CD inclusion compound were （77.31±0.51）％ and （5.31±0.27）％. Accumulative release rates of IDP， IDP-β-CD inclusion compound （by freeze-drying and spray drying） were 37.2％， 42.5％ and 81.9％ within 12 h， respectively. Compared with IDP raw material， accumulative release rate of IDP-β-CD inclusion compound increased significantly after spray drying. CONCLUSIONS： Established method is simple and accurate. The optimal preparation technology of inclusion compound is stable and feasible. IDP-β-CD inclusion compound is prepared successfully. The inclusion compound prepared by spray drying shows higher release rate.