Quality Evaluation of Potentilla fruticosa L. by High Performance Liquid Chromatography Fingerprinting Associated with Chemometric Methods

RESEARCH ARTICLE Quality Evaluation of Potentilla fruticosa L. by High Performance Liquid Chromatography Fingerprinting Associated with Chemometric Methods Wei Liu1,2, Dongmei Wang1, Jianjun Liu3, Dengwu Li1*, Dongxue Yin4* 1 College of Forestry, Northwest A&F University, Yangling, China, 2 Agricultural College, Henan University of Science and Technology, Luoyang, China, 3 College of Landscape Architecture and Arts, Northwest A&F University, Yangling, China, 4 College of Agricultural Engineering, Henan University of Science and Technology, Luoyang, China * (DWL); (DXY) Abstract OPEN ACCESS Citation: Liu W, Wang D, Liu J, Li D, Yin D (2016) Quality Evaluation of Potentilla fruticosa L. by High Performance Liquid Chromatography Fingerprinting Associated with Chemometric Methods. PLoS ONE 11(2): e0149197. doi:10.1371/journal.pone.0149197 Editor: Joshua L Heazlewood, The University of Melbourne, AUSTRALIA Received: August 6, 2015 Accepted: January 28, 2016 Published: February 18, 2016 Copyright: © 2016 Liu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the paper. Funding: This work was supported by the program from the Forestry Research Foundation for the Public Service Industry of China (Grant numbers: 200904004; http://english.forestry.gov.cn/web/index. do). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The present study was performed to assess the quality of Potentilla fruticosa L. sampled from distinct regions of China using high performance liquid chromatography (HPLC) fingerprinting coupled with a suite of chemometric methods. For this quantitative analysis, the main active phytochemical compositions and the antioxidant activity in P. fruticosa were also investigated. Considering the high percentages and antioxidant activities of phytochemicals, P. fruticosa samples from Kangding, Sichuan were selected as the most valuable raw materials. Similarity analysis (SA) of HPLC fingerprints, hierarchical cluster analysis (HCA), principle component analysis (PCA), and discriminant analysis (DA) were further employed to provide accurate classification and quality estimates of P. fruticosa. Two principal components (PCs) were collected by PCA. PC1 separated samples from Kangding, Sichuan, capturing 57.64% of the variance, whereas PC2 contributed to further separation, capturing 18.97% of the variance. Two kinds of discriminant functions with a 100% discrimination ratio were constructed. The results strongly supported the conclusion that the eight samples from different regions were clustered into three major groups, corresponding with their morphological classification, for which HPLC analysis confirmed the considerable variation in phytochemical compositions and that P. fruticosa samples from Kangding, Sichuan were of high quality. The results of SA, HCA, PCA, and DA were in agreement and performed well for the quality assessment of P. fruticosa. Consequently, HPLC fingerprinting coupled with chemometric techniques provides a highly flexible and reliable method for the quality evaluation of traditional Chinese medicines. Competing Interests: The authors have declared that no competing interests exist. PLOS ONE | DOI:10.1371/journal.pone.0149197 February 18, 2016 1 / 20 Quality Evaluation of Potentilla fruticosa L Introduction Traditional Chinese medicine (TCM), with a history of five thousand years, is still in extensive demand [1]. TCM possesses a significant position in the Chinese health system [2] and is being closely examined for the development of novel pharmaceuticals [3,4]. However, challenges for the guarantee of quality of TCM accumulate gradually. There has always been resistance to the adoption of TCM worldwide because of its complexity, the presence of unknown components and the lack of quality control. Chromatographic fingerprint analysis of key components is regarded as a reasonable approach for the quality evaluation of complicated TCMs [5]. A chromatographic fingerprint displays an average chromatographic map of all the samples, rather than a chromatogram of an individual sample [6]. This differs from conventional practice in which one or more components are chosen as active markers for detection and quality evaluation. Fingerprinting relies on the intrinsic relationships between multiple components and generates a defining pattern for TCM samples. Chromatographic fingerprinting, a more important technique for insuring the quality of Chinese medicines and their products, has been acknowledged extensively by many countries and organizations [7,8] such as the European Medicines Agency, the US Food and Drug Administration, the British Herbal Medicine Association and the Indian Drug Manufacturers’ Association [5]. To facilitate the quality assessment for vast and varied TCMs, the World Health Organization (WHO) has accepted chromatographic fingerprinting as a technique for the evaluation of medicinal species [7–10]. Hence, chromatographic fingerprinting has received increasing attention recently among accessible quality control techniques. Chemometric methods, especially cluster analysis and principle component analysis (PCA), which collect chemical profiles objectively, have been widely applied for assortment and identification in analyzing the chemical information of herbal medicines [11,12]. Furthermore, HPLC techniques coupled with multivariate statistical methods (chemometric methods) have been employed extensively to classify and distinguish various herbs [8,13–17]. Potentilla fruticosa L., a member of the Rosaceae family, is commonly used as a natural tea and also as an important TCM [18,19]. Apart from its common applications as a garden plant, a food additive and in cosmetics [20,21], the plant, commonly known as the “Jinlaomei drug” in China, has numerous medicinal virtues for strengthening the stomach and the spleen, promoting metabolism, regulating menstruation and for relieving feelings of tiredness [19,22]. Modern academic studies have revealed that the medical foundations of P. fruticosa are related to various chemical ingredients [23–27] that have strong antioxidant activity [28–30] and that are contained in the leaves. P. fruticosa is native to North America and is widely distributed in the Qinghai, Gansu, Ningxia, Sichuan, Yunnan and Tibet regions in China [19]. For this widespread species, the active ingredients may vary, thus the contents, properties and proportions of the constituents vary because of the distribution in different geological zones. This will cause the same species from different growing regions to possess different therapeutic properties, making the quality assessment of P. fruticosa extr (...truncated)