Compared with UPLC-MS, gas chromatography-mass spectrometry (GC-MS) has a simpler sample pretreatment process and integrates sampling, concentration, and injection together, which is cost-effective and labor saving. In recent years, with the development of analytical technology, ultra-high performance liquid chromatography (UHPLC) combined with mass spectrometry (MS), which has the characteristics of high sensitivity, high resolution and high precision mass measurement, has been extensively developed to discriminate ginseng based on the variety of ginsenosides. Therefore, sophisticated analytical techniques for the chemical phenotype are crucial for chemical composition detection. The secondary metabolites are affected by species, growth environment and harvest time, but are not dependent on the external shape of the herbs. Thus, the differentiation of MCG and GCG is essential for the effectiveness, safety, and quality stability of ginseng. In addition, the different growth environment leads to the diversity of secondary metabolites, which results in different pharmacological activities and clinical values. The price of MCG is generally higher than that of GCG, so adulteration or falsification has always been widespread in the market. Due to the high price and low output of WG, the market is dominated by MCG and GCG. Different growth environments lead to the different appearance of ginseng, but it is extremely difficult to distinguish them when the ginseng samples are cut into slices or ground into powder. MCG is planted artificially in mountain forests and grows naturally, GCG is planted artificially in farmland, while WG grows naturally in mountains and forests. According to the different growth environments and diverse cultivation modes, ginseng is mainly divided into three categories: Mountain-Cultivated Ginseng (MCG), Garden-Cultivated Ginseng (GCG), and Wild Ginseng (WG). It is called “Ginseng” because its rhizome looks like a person. Ginseng, a perennial herb of the Acanthopanax family, is known as the king of herbs and also the king of medicine, and has been used clinically for thousands of years in Asian countries. The proposed approach could be applied to directly distinguish MCG and GCG with different growth years and to identify the differentiation chemo-markers, which is an important criterion for evaluating the effectiveness, safety, and quality stability of ginseng. Similarly, GCG 5-,10-,15-years samples were also separated into three groups, and six potential growth-year-dependent markers were determined. Moreover, MCG 5-,10-,15-years samples were divided into three blocks, and 12 potential growth-year-dependent markers enabled differentiation. MCG 5-,10-,15-years and GCG 5-,10-,15-years samples were mainly divided into two groups by unsupervised principal component analysis (PCA), and 5 potential cultivation-dependent markers were discovered based on orthogonal partial least squares-discriminant analysis (OPLS-DA). The base peak intensity chromatograms were subjected to multivariate statistical analysis to comprehensively compare the chemical differences among the above samples. As a result, we characterized, for the first time, 46 volatile components from all the samples by using the NIST database and the Wiley library. In the present study, a headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME-GC-MS) coupled with chemometrics approach was developed to characterize the volatile component profiles in MCG and GCG with 5-,10-,15-growth years, and subsequently to discover differentiating chemical markers. Thus, the authentication of MCG and GCG is crucial for the effectiveness, safety, and quality stability of ginseng. Moreover, there is significant price difference between them, which leads to the widespread adulteration or falsification in the market. Although there are differences in the appearance of Mountain-Cultivated Ginseng (MCG) and Garden-Cultivated Ginseng (GCG), it is very difficult to distinguish them when the samples are processed to slices or powder.
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