Screening of natural drug molecules against Fusarium oxysporum of ginseng root rot based on machine learning / 药学学报

italic>Fusarium oxysporum widely exists in farmland soil and is one of the main pathogenic fungi of root rot, which seriously affects the growth and development of plants and often causes serious losses of cash crops. In order to screen out natural compounds that inhibit the activity of Fusarium oxysporum more economically and efficiently, random forest, support vector machine and artificial neural network based on machine learning algorithms were constructed using the information of known inhibitory compounds in ChEMBL database in this study. And the antibacterial activity of the screened drugs was verified thereafter. The results showed that the prediction accuracy of the three models reached 77.58%, 83.03% and 81.21%, respectively. Based on the inhibition experiment, the best inhibition effect (MIC = 0.312 5 mg·mL-1) of ononin was verified. The virtual screening method proposed in this study provides ideas for the development and creation of new pesticides derived from natural products, and the screened ononin is expected to be a potential lead compound for the development of novel inhibitors of Fusarium oxysporum.

Comprehensive evaluation of Pinellia ternata germplasm resources based on phenotypic trait classification / 中国中药杂志

The evaluation of germplasm resources is the prerequisite for the development, utilization, and conservation of Chinese medicinal resources. The selection of excellent germplasm is the key to the breeding and orderly production of Pinellia ternata. In this study, 21 germplasm materials of P. ternata from major production areas in China were collected and analyzed for population diversity after phenotypic preliminary screening. The results have revealed that the P. ternata population has abundant phenotypic variation, and the phenotypic changes could be divided into five phenotypes in terms of organ trait variation. Further analysis of variation in 20 quantitative traits of the population revealed that the coefficient of variation for adenosine content(339.05%) was the largest, while the coefficient of variation for the underground plant height(16.35%) was the smallest. Correlation analysis showed that there was a strong correlation among various traits, with 52 pairs of traits showing highly significant correlation(P<0.01) and 19 pairs of traits showing a significant correlation(P<0.05). The 21 germplasms in the test could be classified into three major clusters by cluster analysis, with Cluster Ⅱ having the highest number and content of nucleosides, making it suitable for the selection and breeding of P. ternata varieties with high content of nucleosides. The yield in Cluster Ⅲ was higher than that in other groups, making it suitable for the selection and breeding of P. ternata varieties with a high yield. All trait indicators could be simplified into five principal component factors through principal component analysis, and the cumulative contribution rate was up to 86.04%. Further, comprehensive analysis using membership function and stepwise regression analysis identified nine traits, such as plant height, main leaf length, and underground plant height as characteristic indicators for the comprehensive evaluation of germplasm resources of P. ternata. BX007, BX008, and BX005 were identified as germplasms with both high yield and high uridine content, with BX007 having the highest uridine content of 479.51 μg·g~(-1). It belonged to the germplasm of P. ternata with double bulbils and could be cultivated as a potential good variety. Based on the phenotypic classification of P. ternata, systematic resource evaluation was carried out in this study, which could lay a foundation for the excavation of genetic resources and the breeding of new varieties of P. ternata.

Identification of mixed medicinal powder of Epimedii Folium with different origins based on pyrosequencing technology / 药学学报

There are many multi-original medicinal materials in Chinese Pharmacopoeia, and the mixed use of medicinal materials from different sources is common, which has certain influence on the stability of clinical medication. In this study, pyrosequencing technology was used to screen species-specific single nucleotide polymorphisms (SNP) from commonly used DNA barcode sequences, and a rapid and accurate molecular identification method for original species in mixed medicinal powder of Epimedii Folium was established. Multiple sequence alignment analysis showed that the 176th (C/T) mutation and the 196th (A/G) mutation of ITS, the 123rd (C/G) mutation of matK and the 892nd (A/C) mutation of rbcL could be used as the unique SNPs of E. sagittatum, E. koreanum, E. brevicornu and E. pubescens, respectively. In this study, the applicability of pyrosequencing and Sanger sequencing methods in the sequencing of mixture samples was investigated from the perspective of sensitivity and stability. Pyrosequencing method has higher detection sensitivity than Sanger sequencing method for low content samples in the mixed samples. Stability analysis showed that pyrosequencing technology could still obtain effective sequencing results for the amplified products of template DNA after 45 min of 95 ℃ high temperature water bath, while the critical point of Sanger sequencing method was 30 min. In this study, a new identification technology of Epimedii Folium mixed powder primordial species based on pyrosequencing and specific SNP was developed, which can quickly and accurately identify the mixed use of Epimedii Folium with high sensitivity and stability, and can also support the identification of different primordial species and mixed powder primordial herbs, which is conducive to ensuring the consistency and stability of clinical medication.

Optimal Potassium Application Rate for Panax ginseng / 中国实验方剂学杂志

ObjectiveThe law of fertilizer requirement serves as the basis for the fertilization of medicinal plants， development of special fertilizer， and high-quality medicinal materials. MethodThis study aims to explore the optimal potassium application rate for Panax ginseng to achieve high yield and quality of the medicinal material and targeted management of potassium fertilizer. To be specific， 6 concentration gradients （0， 2， 4， 8， 10， and 12 mmol·L-1） of potassium sulfate （potassium fertilizer） were designed and applied to the 4-year-old P. ginseng in CK， C1， C2， C3， C4， and C5 treatments， respectively. Thereby， the influence of potassium concentration on P. ginseng was observed. ResultWhen potassium sulfate was applied at 8 mmol·L-1， P. ginseng had the chlorophyll content of 32.13%， net photosynthetic rate of 2.548 8 µmol·m-2·s-1， and activities of superoxide dismutase （SOD）， peroxidase （POD）， and catalase （CAT） significantly higher than those in the CK， C1， C4， and C5 treatments （P<0.05）. The average fresh weight of P. ginseng roots was 6.25 g， 134% up from the CK， and the content of ginsenoside Rg1 （5.24 mg·g-1） and Re （4.17 mg·g-1） and total saponins （12.33 mg·g-1） was significantly higher than that in CK and other treatments （P<0.05）. Thus， 8 mmol·L-1 potassium sulfate was most favorable for the growth and effective component accumulation of four-year-old P. ginseng. ConclusionThis study expounds the effect of potassium fertilizer on the yield and quality of P. ginseng， which is expected to help guide the precise application of potassium fertilizer in P. ginseng production in the field and lay a theoretical basis for the development of special fertilizer for P. ginseng and the optimization of fertilization technology.

Resistance Evaluation of Different Phenotypes of Farmland Ginseng Radix et Rhizoma Germplasm Under High Light Stress / 中国实验方剂学杂志

Objective:To investigate the physiological response of Ginseng Radix et Rhizoma with different phenotypes to high light stress under farmland cultivation mode， and to provide theoretical support for breeding of and fine management of new varieties of farmland ginseng. Method:Four-year-old ginseng plants with different stem colors were used as materials， and blue film was replaced by the colorless and translucent film for performing high light stress and investigating the change of growth status， light response curve， photosynthetic and fluorescence parameters of ginseng leaves. Meanwhile， the physiological adaptability and cell ultrastructural differences of ginseng with different phenotypes for strong light were compared by analyzing the variation of leaf ultrastructural characteristics before and after the stress. Result:The color of ginseng leaves became weak and the content of chlorophyll was greatly decreased with burning phenomenon on the leaf margin under high light stress. The maximum net photosynthetic rate and light saturation point of purple-stem ginseng were higher than those of green-stem ginseng. Transpiration rate， water use efficiency and other gas exchange parameters of purple-stem ginseng had adversity advantages， photosynthetic electron transport rate， maximum photochemical efficiency， photochemical quenching coefficient and other chlorophyll fluorescence parameters were higher than those of green-stem ginseng. There were changes in ultrastructure of the two germplasms， and the plasmolysis of green-stem ginseng was more obvious， its chloroplast membrane ruptured， the contents were exuded and the accumulation of starch grains and osmiophilic bodies increased. The chloroplast membrane structure of purple-stem germplasm was relatively stable， and its number of multivesicular bodies increased significantly by comparing with that of green-stem ginseng under high light. Conclusion:High light stress inhibits the leaf growth of farmland ginseng with different stem colors. The photosynthetic efficiency of green-stem ginseng is obviously reduced， and the integrity of chloroplast is damaged， leading to the weak physiological resistance. The purple-stem ginseng can reduce the damage of the photosynthetic system of plants under high light stress by its special cell structure and non-photochemical quenching advantages. Therefore， the purple-stem ginseng can be cultivated into a new resistant variety.

Molecular identification and alkaloids content of endangered Chinese medicinal plant Coptis chinensis var. brevisepala / 中国中药杂志

According to the records of Chinese materia medica,Coptis chinensis var. brevisepala is an authentic Chinese medicinal plant highly recommended by ancient physicians since its rhizome is like a string of beads and has a good medicinal value. However,its medicinal components and values remain to be studied as it is endangered because of overexploitation. Therefore,this study aims to quantitatively determine its effective components based on UPLC-QTOF-MS,and to compare the contents of isoquinoline alkaloids in C.chinensis var. brevisepala with those in other Coptis species. Meanwhile,molecular methods accurately identified 12 batches of C. chinensis var. brevisepala,9 batches of C. chinensis,4 batches of C. deltoidea,and 1 batch of C. teeta. Gradient elution was performed with Waters CORTECS C18 column( 4. 6 mm× 150 mm,2. 7 μm) and the mobile phase acetonitrile-water with 0. 4% formic acid. Mass spectrometry was conducted in ESI positive mode. The quantitative results showed that 8 main alkaloids had a good linear relationship within the concentration range( R~2>0. 996),with the recovery rate of 95. 18%-105. 0% and the RSD of 0. 28%-3. 7%. Compared with that of other Coptis species,the rhizome of C. chinensis var. brevisepala had the highest contents of berberine and columbamine. The total content of the 8 alkaloids in C. chinensis var. brevisepala was similar to that in C. chinensis but higher than that of the other two species. PCA was performed to compare the alkaloids among the 4 species. Besides,the 8 alkaloids were evaluated in different parts of C. chinensis var. brevisepala. The results indicate that this method is reliable and efficient and can provide a reference for the quality research.

Complete chloroplast genome of Salvia plebeia: organization, specific barcode and phylogenetic analysis / 中国天然药物

Salvia plebeia has been in use as traditional Chinese medicine (TCM) for more than 500 years. In this study, the complete chloroplast (cp) genome of S. plebeia was sequenced, assembled and compared to those of other five published Salvia cp genomes. It was found that the cp genome structure of S. plebeia was well conserved and had a total size of 151 062 bp. Four parameters were used to display the usage conditions of the codons of the amino acids in Salvia genus. Although the number of protein-coding genes in each species was the same, the total number of codons was different. Except for amino acids Trp and Met whose Relative Synonymous Codon Usage (RSCU) value of one condon was equal to 1, the remaining 19 amino acids had 1-3 preferred codons. The preferred codon names of each amino acid were coincident. The period size for the tandem repeats of six species ranged from 9 to 410 bp. Salvia cp genomes mainly possessed tandem repeats with a copy number less than or equal to 3. The sequence length of tandem repeats of the six species ranged from 25 to 824 bp. Highly viarable regions including four intergenic spacers and six partial genes were discovered as potential specific barcodes for Salvia species through cp genome-wide comparison. Finally, we performed phylogenetic analyses based on the complete cp genome and coding sequences respectively. These results provide information to help construct the cp genome library for Salvia, which may support studies of phylogenetics, DNA barcoding, population and transplastomics.

Prediction of the globally ecological suitability of Panax quinquefolius by the geographic information system for global medicinal plants (GMPGIS) / 中国天然药物

American ginseng (Panax quinquefolius L.) is a well-known Asian traditional herbal medicine with a large market demand. The plant is native to eastern North America, and its main producing areas worldwide are decreasing due to continuous cropping obstacles and environmental changes. Therefore, the identification of maximum similarities of new ecological distribution of P. quinquefolius, and prediction of its response to climate change in the future are necessary for plant introduction and cultivation. In this study, the areas with potential ecological suitability for P. quinquefolius were predicted using the geographic information system for global medicinal plants (GMPGIS) based on 476 occurrence points and 19 bioclimatic variables. The results indicate that the new ecologically suitable areas for P. quinquefolius are East Asia and the mid-eastern Europe, which are mainly distributed in China, Russia, Japan, Ukraine, Belarus, North Korean, South Korea, andRomania. Under global climate change scenarios, the suitable planting areas for P. quinquefolius would be increased by 9.16%-30.97%, and expandingnorth and west over the current ecologically suitable areas by 2070. The potential increased areas that are ecologically suitable include northern Canada, Eastern Europe, and the Lesser Khingan Mountains of China, and reduced regions are mainly in central China, the southern U.S., and southern Europe. Jackknife tests indicate that the precipitation of the warmest quarter was the important climatic factor controlling the distribution of P. quinquefolius. Our findings can be used as auseful guide for P. quinquefolius introduction and cultivation in ecologically suitable areas.

Species identification of poisonous medicinal plant using DNA barcoding / 中国天然药物

The aim is to select a universal DNA barcode for identifying all poisonous medicinal plants in Chinese pharmacopoeia and their poisonous related species or adulterants. We chose 4 commonly used regions as candidate DNA barcodes (ITS2, psbA-trnH, matK and rbcL) and compared their identification efficiency in 106 species from 27 families and 65 genera totally. Data analysis was performed including the information of sequence alignment, inter/intra-specific genetic distance and data distribution, identification efficiency and the situation of Neighbor-Joining (NJ) phylogenetic trees. We found ITS2 sequence region had high variation, stable genetic distance and identification efficiency relatively. The topological structure of NJ phylogenetic tree showed monophyletic. Our findings show that ITS2 can be applied as a universal barcode for identifying poisonous medicinal plants in Chinese pharmacopoeia and their poisonous related species or adulterants.

Preparation and Quality Evaluation of Standard Decoction of Chrysanthemi Indici Flos Based on Traditional Decoction Process / 中国实验方剂学杂志

Objective:To study the dry extract rate,determination and transfer rate of maker compounds,fingerprint and others of standard decoction of Chrysanthemi Indici Flos and provide basic data for the preparation of this standard decoction and its dispensing granules by establishing 15 batches of standard decoction of Chrysanthemi Indici Flos from 5 different places. Method:The standard decoction of Chrysanthemi Indici Flos was prepared based on the traditional decoction process,the content of linarin was determined by UPLC-DAD,the transfer rate of this composition was calculated,the fingerprint was drawn,the extract powder was prepared by vacuum drying,and the dry extract rate was calculated. Result:The concentration of linarin in 15 batches of standard decoction of Chrysanthemi Indici Flos was 0.19-0.74 g·L-1,the transfer rate of linarin was 21.95%-66.23%,its average transfer rate was 37.12% with RSD of 11.8%,the pH value was 5.1-5.5,the range of dry extract rate was 24.7%-32.5%,the average dry extract rate was 27.87% with RSD of 2.4%.There were 9 major common peaks in the fingerprint and 2 peaks(No. 2 and No. 9) were confirmed,such as chlorogenic acid and linarin. Conclusion:The preparation method in this research conforms to the traditional decoction method and is stable and feasible.It can be used for the preparation and quality evaluation of standard decoction of Chrysanthemi Indici Flos.

Quality Evaluation of Standard Decoction of Zingiberis Rhizoma / 中国实验方剂学杂志

Objective: To establish the quality control methods for the standard decoction of Zingiberis Rhizoma. Method: DNA barcode primitives were identified for the medicinal materials from different origins; according to the standard of Chinese herbal medicine decoction preparation principle,the identified Zingiberis Rhizoma was prepared into standard decoction for analysis. Meanwhile, the extraction method and analysis method were validated from methodologies, and the transfer rate of 6-gingerol as well as the extraction rate of standard decoction of Zingiberis Rhizoma were calculated. In addition,the quality standard of standard decoction of Zingiberis Rhizoma was also established based. The structures of main chromatographic peaks were identified by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) to clarify the main chemical constituents in the standard decoction of Zingiberis Rhizoma. Result: All the samples were identified as Zingiberis Rhizoma. Under the conditions established in this paper,the standard curve of 6-gingerol was Y=661.56X+2.493 3(r=0.999 3),and the RSD was 0.5%in precision test, indicating that the instrument precision was good. The repeatability test showed that the RSD was 0.3%, indicating that the method had good repeatability. The stability test showed that the RSD was 0.4%, indicating that the test solution had good stability within 24 h. The recovery rate was 97.2%and the RSD was 0.6%,indicating that the method was accurate and reliable. 6-gingerol's transfer rate ranged from 31.8%to 57.4%and the extraction rate was within the range of 9.6%-23.1%. The fingerprint similarity of 12 batches of Zingiberis Rhizoma standard decoction was>90%. Conclusion: The established quality control method for Zingiberis Rhizoma was stable and feasible; meanwhile, the standard preparation method for Zingiberis Rhizoma and its quality evaluation system were also established in this study.

Comparative study on standard decoctions of Ophiopogonis Radix and Liriopes Radix / 中国中药杂志

Standard decoction is the core of the pharmacodynamics for water-soluble substance of Chinese materia medica. Its research is of great significance to the research and development of some single ingredients and the classical prescriptions,and it is the only way to transform traditional medication experience into industrial products. In this article,standard decoction research strategies were used for the comparison analysis of Ophiopogonis Radix from Zhejiang province(ZMD),Ophiopogonis Radix from Sichuan province(CMD),and Liriopes Radix(SMD). Regularities were present among different grades of CMD; potential quality markers and pH differences associated with SO2 residues were also found. Finally,the extract powder of Ophiopogonis Radix prepared by mass production process was analyzed and validated,and the results showed that the standard system could be used for the quality control of intermediates and final products. In conclusion,this study can provide reference for the clinical application of Ophiopogonis Radix medicines and provide testing method for higher quality with higher price.

Correlative analysis of agronomic traits and quality of Panax ginseng saponins cultivation in farmland / 中国中药杂志

Cultivated ginseng in the farmland would become the mainly planting mode of Panax ginseng. However,there are relatively few cultivation ginseng varieties for farmland in China. Correlative analysis of qualitity and agronomic traits of P. ginseng cultivation in the farmland could provide a reference for the selection of excellent germplasm and new variety breeding of P. ginseng. In this study,the main index of saponin and agronomic traits of 4-6 years' samples were analyzed by UPLC and measured. The results show that there was significant difference in agronomic indexes of Damaya. The coefficient of variation of the root length( CV = 41. 97%) and fresh weight( CV = 31. 81%) were maximum,and the coefficient of variation of the stems thickness( 16. 72%) and root thickness were minimum. There was a significant correlation between yield and root thickness( P<0. 05). There was significant difference in drug yield of different harvest years( P<0. 05),and the yield of 6-years was 31. 52%-39. 69% higher than 4-years. However,there wasn't significant difference in total ginsenosides between 4 and 6 years old P. ginseng,but there was significant difference in ginseng Rg2,Rc and Rb2( P<0. 05),and the ginsenoside contents of different harvesting years were accorded with the criterion standards of 2015 Chinese Pharmacopoeia. There was no significant correlation between the saponin and the agronomic trait,while there was positive correlation with root thickness( P < 0. 05). Therefore,the stem diameter was positive correlation with yield of P. ginseng. Selection of the stem thickness of seedlings is beneficial to the increase of the yield and breeding of P. ginseng.

Research of pollution-free and precision cultivation system of Chinese herbal medicines / 中国中药杂志

The issues of disordering production and non-standard pesticide application are common in the production of Chinese herbal medicines. Aimed to above problems, research groups built the pollution-free and precision cultivation system of medicinal plants. This system mainly included the precise site selection of medicinal plants based on the GIS technology, modern omics-assisted breeding, metagenomics guiding the soil complex improvement, and the precise field management based on rational application of fertilizer and comprehensive control of disease. At present, the production and distribution of medicinal plants were performed in the many poor counties of the whole nation. The breeding platform of resistant varieties was built, and certificates of new and well-bred varieties were received, in the base of genetic backgrounds of the original species of medicinal plants. The disease incidences were declined after application of these resistant varieties. Additionally, chemical pesticide consumption of medicinal plants (such as Panax ginseng, P. notoginseng, Salvia miltiorrhiza, P. quinquefolium, Schisandra chinensis, Platycodon grandiflorum and P. grandiflorus etc.) reduced by 20%-80% based on the genetic testing technologies of plant diseases and insect pests and safety evaluation of pollution-free pesticides. The application of pollution-free and precision cultivation system of Chinese herbal medicines achieve significantly social, economic and ecological benefits.

Efficacy of the modified incision versus standard incision in proximal femoral nail antirotation for femoral intertrochanteric fractures / 中国组织工程研究

BACKGROUND: Proximal femoral nail antirotation (PFNA) is the most commonly used internal fixation for femoral intertrochanteric fracture. However, a large amount of hidden blood loss makes negative effect on the functional recovery postoperatively. OBJECTIVE: To compare the clinical efficacy of the modified incision and standard incision in PFNA for femoral intertrochanteric fracture. METHODS: Sixty-nine patients with femoral intertrochanteric fractures were analyzed retrospectively, and were then divided into two groups, followed by treated with modified incision of PFNA (group A) or standard incision of PFNA (group B). The postoperative biomechanical stability, fracture healing time, complications, Harris scores at the last follow-up, proximal incision length, operation time, and blood loss were compared between two groups. RESULTS AND CONCLUSION: (1) All the patients were followed up for more than 12 months. The fracture healing time, Harris scores at the last follow-up and incidence of postoperative complications did not differ significantly between two groups. (2) The intraoperative blood loss, total blood loss and total blood transfusion in the group A were significantly less than those in the group B (P < 0.05). (3) The proximal incision length and operation time in the group A were significantly shorter than those in the group B. (4) These results manifest that in the treatment of femoral intertrochanteric fracture, both methods exhibit good biomechanical properties and stability. Notably, compared with the standard incision method, the modified incision method has less trauma, shorter operation time, less blood loss and blood transfusion.

A meta-analysis of risk factors of postoperative delirium of elderly hip fracture patients in China / 中国组织工程研究

BACKGROUND: At present, there is no consensus on the risk factors for delirium after hip fracture in the elderly, and there is no risk prediction system that can effectively assess the risk of delirium after hip fracture in the elderly. OBJECTIVE: To identify the risk factors of postoperative delirium of elderly hip fracture. METHODS: Studies about delirium of elderly hip fracture patients were retrieved by computer. Quality of the studies was assessed. Analysis of sensitivity and heterogeneity was performed by RevMan 5.3 software and cumulative effects were calculated by either fixed or random effects models. RESULTS AND CONCLOUSION: (1) Totally 15 studies included 872 cases of delirium and 3 221 cases of non-delirium. (2) The results of meta-analysis showed that:univariate analysis indicated that preoperative cognitive dysfunction[pooled OR=4.99,95%CI(2.66,9.37),P=0.000],age[pooled MD=3.60,95%CI(2.21, 5.00),P=0.000],preoperative complications ≥ 3[pooled OR=2.83,95%CI(2.12,3.79),P=0.000],preoperative hemoglobin<100 mg/L[pooled OR=2.09, 95%CI(1.17,3.76),P=0.01],preoperative albumin<35 g/L[pooled OR=2.29,95%CI(1.77,2.97),P=0.01],general anesthesia[pooled OR=2.17,95%CI(1.41, 3.34),P=0.000 4],the type or treatment of hip fracture[pooled OR=1.36,95%CI(1.04,1.78),P=0.02],operation time[pooled OR=2.88,95%CI(1.42,5.82), P=0.003],and intraoperative blood loss[pooled MD=36.97,95%CI(25.74,48.19),P=0.000]were the risk factors of postoperative delirium of elderly hip fracture patients.(3)Multivariate analysis showed that preoperative cognitive dysfunction[pooled=4.94,95%CI(2.23,10.95),P=0.000],age[pooled MD=2.84,95% CI(1.89, 3.78),P=0.000],preoperative complications ≥ 3[pooled OR=3.05,95%CI(2.11,4.41),P=0.000],general anesthesia[pooled OR=4.29,95%CI(1.40,13.14), P=0.01],and operation time ≥ 2.5 hours[pooled OR=2.62,95%CI(1.68,4.08),P=0.000]were independent risk factors for postoperative delirium of elderly hip fracture patients. (4) In conclusion, the independent risk factors of postoperative delirium of elderly hip fracture patients are preoperative cognitive dysfunction, age, preoperative complications ≥ 3, general anesthesia and operation time ≥ 2.5 hours. The type of fracture, preoperative waiting time, and type of operation are not related to postoperative delirium. However, due to the low quantity and quality of the included literature, the conclusion needs the support from many high-quality studies.

Key techniques for precision cultivation of nitrogenous fertilizer of pollution-free ginseng / 中国中药杂志

Planting pollution-free farmland is the main mode of industrialization of ginseng cultivation, fine management of nitrogen fertilizer ginseng pollution-free farmland cultivation technology system is one of the key factors. In order to investigate the effect of nitrogenous fertilizer on the accumulation of ginseng biomass and saponins synthesis in vegetative growth stage, two-years-old ginsengs were used as test materials in this study. The test materials were cultivated by Hoagland medium with different nitrogen concentration (0，10，20，40 mg·L⁻¹) for 40 days. During the cultivation, photosynthetic rate was measured four times. After 40 days cultivation, chlorophyll content, stem diameter and the spatiotemporal expression of saponin synthesis related genes PgHMGR and PgSQE were tested. The results showed that there were significant differences in the photosynthetic rate and chlorophyll content among different nitrogen concentrations. The relative expression level of PgHMGR gene and PgSQE gene in root, stem and leaves of ginseng were different. Ginseng seedlings cultivated by 20 mg·L⁻¹ nitrogen possess the highest photosynthetic rate and chlorophyll content, while PgHMGR and PgSE showed the highest gene expression level. The optimal nitrogen concentration for the growth of 2-years-old ginseng might be 20 mg·L⁻¹ with 57.14 g ammonium nitrate each plant or pure 20.00 mg nitrogen each plant. It is concluded that this concentration is the most suitable concentration for the ginsenoside synthesis. Pollution-free ginseng with fine nitrogen fertilizer cultivation is conducive to the production of high quality and efficient ginseng medicinal materials. It lays a theoretical foundation for the rational fertilization and environment-friendly sustainable ecological ginseng planting industry.

DNA barcoding identification of endangered medicinal plants of Orchidaceae / 中国中药杂志

In this study, DNA barcoding was used to validate the traditional morphological classification of medicinal plants of Orchidaceae. The 163 samples of 135 species belong to 49 genera which have been confirmed by morphological identification were collected. Candidate sequences, including matK, psbA-trnH and ITS2 sequences, were amplified, bidirectionally sequenced, and assembled. All the sequences were blasted to GenBank database at NCBI, then analyzed using Neighbor-joining tree method by MEGA 7.0. The results showed that the DNAs of 163 samples were successfully extracted. The amplification efficiency of matK, psbA-trnH and ITS2 sequences were 100%, 100% and 98.77%, respectively. The 487 sequences were obtained, 345 sequences of which have matched corresponding sequences in the GenBank database and 142 sequences were new sequences. The topology of NJ tree which were constructed with the matK sequences was better than the trees of psbA-trnH and ITS2 sequences. In conclusion, the matK, psbA-trnH and ITS2 sequences were complementary and suitable for identification of medicinal plants of Orchidaceae. DNA barcoding can be used as an auxiliary means for identification of medicinal plants of Orchidaceae.

Analysis of varieties and standards of Composite medicinal plants used in Dai medicine / 中国中药杂志

The study aims to analyze the varieties and standards of compositae medicinal plants used in Dai medicine. The results showed that there were 78 species (including varieties) compositae plants recorded in literatures, which belongs to 63 medicinal materials varieties. And 47 original plants (60.25%) were recorded in Chinese medicinal material standards. In those standards and literatures of Dai medicine, there are great differences in translated Chinese names, original plants, medicinal parts, and efficacy of medicinal plants. Therefore, the variety systematization and the quality standards of Dai medicine should be strengthened.

Soil improvement promoted micro-ecology of farmlands for ginseng cultivation / 中国中药杂志

This study has revealed the change of the soil micro-ecology of farmlands, which used for ginseng cultivation, brought by comprehensive soil improvement. The process of soil improvement was described as follows： soil was sterilized using trichloronitromethane, and then perilla seeds were planted. After growing up, the perillas were turned over into the field and fermented, then organic fertilizer was added. Rotary tillages were carried out during the intervals. Physical and chemical properties of treated soil were measured, as well as microbial diversity, which was illustrated using 16s high through-put sequencing. The survival rate and growth data of ginseng seedlings were recorded. The analysis showed that after improvement, the soil organic matter content was increased and soil bulk density was decreased, compare to the controls, and the fertility in 0-20 cm of soil layer was increased in the treatment. Additionally, the soil microbial diversity was changed greatly. In detail, alpha diversity of the soil decreased after soil improvement while the beta diversity increased. In order to verify the achievement of soil improvement, ginseng seedlings were planted. Compared to the untreated land blocks, the survival rate of ginseng on improved blocks was increased up to 21.4%, and the ginseng physiological index were all better than the controls. Results showed that comprehensive soil improvements including soil sterilization, green manure planting and organic fertilization application effectively improved the soil micro-ecology in farmlands. This study will pave the way for the future standardization of ginseng cultivation on farmlands.