Novel SNP markers on ginsenosides biosynthesis functional gene for authentication of ginseng herbs and commercial products

Panax ginseng and Panax quinquefolius have similar bioactive components and morphological characteristics, but they are known to have different medicinal values, high-sensitive and accurate method is expected to identify the sources of ginseng products and evaluate the quality, but with a huge challenge. Our established UHPLC-TOF/MS method coupled with orthogonal partial least squares discriminant analysis(OPLS-DA) model based on 18 ginsenosides was applied to discriminate the sources of raw medicinal materials in ginseng products, and nested PCR strategy was used to discover 6 novel single nucleotide polymorphism(SNP)sites in functional dammarenediol synthase(DS) gene for genetic authentication of P. ginseng and P. quinquefolius for the first time.OPLS-DA model could identify the sources of raw ginseng materials are real or not. SNP markers were applied to identify ginseng fresh samples as well as commercial products, and proved to be successful. This established molecular method can tell exact source information of adulterants, and it was highly sensitive and specific even when total DNA amount was only 0.1 ng and the adulteration was as low as 1%. Therefore, this study made an attempt at the exploration of new type SNP marker for variety authentication and function regulation at the same time, and the combination of chemical and molecular discrimination methods provided the comprehensive evaluation and authentication for the sources of ginseng herbs and products.

Discovery of differential sequences for improving breeding and yield of cultivated Ophiocordyceps sinensis through ITS sequencing and phylogenetic analysis

To accelerate the breeding process of cultivated Ophiocordyceps sinensis and increase its yield,it is important to identify molecular fingerprint of dominant O.sinensis.In the present study,we collected 3 batches of industrially cultivated O.sinensis product with higher yield than the others and compared their internal transcribed spacer(ITS)sequences with the wild and the reported.The ITS sequence was obtained by bidirectional sequencing and analyzed with molecular systematics as a DNA barcode for rapid and accurate identification of wild and cultivated O.sinensis collected.The ITS sequences of O.sinensis with detailed collection loci on NCBI were downloaded to construct a phylogenetic tree together with the sequences obtained from the present study by using neighbor-joining method based on their evolution relationship.The information on collection loci was analyzed with ArcGIS 10.2 to demonstrate the geographic distribution of these samples and thus to determine the origin of the dominant samples.The results showed that all wild and cultivated samples were identified as O.sinensis and all sequences were divided into seven phylogenetic groups in the tree.Those groups were precisely distributed on the map and the process of their system evolution was clearly presented.The three cultivated samples were clustered into two dominant groups,showing the correlation between the industrially cultivated samples and the dominant wild samples,which can provide references for its optimized breeding in the future.

A new approach for identification of medicinal almonds by fourier transform infrared spectroscopy and systematic clustering of characteristic peaks

Medicinal almonds have been used for over 2 000 years and its clinical efficacy includes relieving cough and asthma. The domestic market in China is flooded with different kinds of dried almonds, such as bitter almond(Armeniacae Semen Amarum, AAS),sweet almond(Armeniacae Semen Dulce, ADS), salted almond(Armeniacae Semen Salsa, ASS), and their sulfur-fumigating products(Armeniacae Semen Sulphur Fumabat, ASFS). Wide varieties of almonds may lead to uncertain efficacy, aberrant quality, and even increased safety risk. However, the authentication method for medicinal almonds has not been reported, although imposters may lead to ineffective medical response. In the present study, Fourier transform infrared spectroscopy(FTIR) and the 2-dimensional infrared(2 D-IR) spectroscopy were used to identify different almonds, which were extracted with different solvents including water, methanol, ethanol, chloroform and ethyl acetate, respectively. A new simple FTIR method was developed in the present study. According to the gradient solvent polarity, a new 2 D IR method was first developed, and the commodities of almonds in China were analyzed by using the FTIR spectroscopy supported by hierarchical clustering of characteristic peaks. Moreover, 5-hydroxymethyl-2-furfural could be used as a detection index and control target in the quality control of medicinal almonds.