Responses of soil nutrients and rhizosphere microbial communities of a medicinal plant Pinelliaternata to vermicompost.

Vermicomposting is an important strategy for restoring soil function and fertility. However, information on the effects of vermicompost application in intensive Pinellia ternata planting systems has rarely been reported. Here, we focus on the effects of different vermicompost levels and chemical fertilizer (CF) strategies on soil chemical properties, soil enzymes, and soil rhizosphere microbial communities (bacteria and fungi) in a field experiment. Compared to no added fertilizers (CK), vermicompost was more effective than the CF treatment in increasing P. ternata yield. We found that the 5 t ha-1 vermicompost treatment (VC2) significantly increased the tuber yield by 44.43% and 6.55% compared to the CK and CF treatment, respectively, and water-soluble exudates by 6.56% and 9.63% (P < 0.05). The vermicompost and CF treatments significantly increased the total phosphorus (TP), urease (Ure), and soil catalase (Cat) contents (P < 0.05). Compared to the vermicompost and CK treatments, the CF treatment significantly decreased soil organic carbon (SOC), C/N ratio, and soil acid phosphatase (Pac) (P < 0.05). Redundancy analysis (RDA) showed that Ure and total potassium (TK) were the major drivers in the bacterial community, whereas TP, total nitrogen (TN), Pac, and TK were the major drivers in the fungal community. We also found a positive correlation between soil enzyme activities, including between Ure and bacterial genera (Clostridium, Pseudoclavibacter, Stella, Hyphomicrobium, Mesorhizobium, and Adlercreutzia). In summary, vermicompost application promotes P. ternata soil microecosystems and improves soil fertility, soil enzyme activities, and rhizosphere microbial structure and function. Vermicomposting is a novel and promising approach to sustainable ecological cultivation of Chinese herbs via the promotion of soil properties and beneficial organisms.

Indispensable biomolecules for plant defense against pathogens: NBS-LRR and "nitrogen pool" alkaloids.

In a complex natural environment, plants have evolved intricate and subtle defense response regulatory mechanisms for survival. Plant specific defenses, including the disease resistance protein nucleotide-binding site leucine-rich repeat (NBS-LRR) protein and metabolite derived alkaloids, are key components of these complex mechanisms. The NBS-LRR protein can specifically recognize the invasion of pathogenic microorganisms to trigger the immune response mechanism. Alkaloids, synthesized from amino acids or their derivatives, can also inhibit pathogens. This study reviews NBS-LRR protein activation, recognition, and downstream signal transduction in plant protection, as well as the synthetic signaling pathways and regulatory defense mechanisms associated with alkaloids. In addition, we clarify the basic regulation mechanism and summarize their current applications and the development of future applications in biotechnology for these plant defense molecules. Studies on the NBS-LRR protein and alkaloid plant disease resistance molecules may provide a theoretical foundation for the cultivation of disease resistant crops and the development of botanical pesticides.

Predictive Analysis of Quality Markers of Atractylodis Rhizoma Based on Fingerprint and Network Pharmacology.

BACKGROUND: Atractylodes chinensis (DC.) Koidz. (A. chinensis) is a perennial herbaceous plant that is widely used as a Chinese medicine herb for gastric diseases. However, the bioactive compounds of this herbal medicine have not been defined, and quality control is imperfect. OBJECTIVE: Although the method of quality evaluation method for A. chinensis by high-performance liquid chromatography (HPLC) fingerprinting has been reported in related papers, it remains unknown whether the chemical markers selected are representative of their clinical efficacy. To develop methods for qualitative analysis and improved quality evaluation of A. chinensis. METHOD: In this study, HPLC was used to establish fingerprints and conduct similarity evaluation. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to reveal the differences of these fingerprints. Network pharmacology was used to analyze the corresponding targets of the active ingredients. Meantime, an active ingredient-target-pathway network was constructed to investigate the characteristics of the medical efficacy of A. chinensis and to predict potential Q-markers. RESULTS: Combining network pharmacological effectiveness and composition specificity with the Q-marker concept, atractylodin (ATD), ß-eudesmol, atractylenolide Ι (AT-I) and atractylenolide III (AT-III) were predicted to be potential Q-markers of A. chinensis that showed anti-inflammatory, antidepressant, anti-gastric, and antiviral effects by acting on 10 core targets and 20 key pathways. CONCLUSIONS: The HPLC fingerprinting method established in this study is straightforward, and the identified four active constituents can be used as Q-markers of A. chinensis. These findings facilitate effective quality evaluation of A. chinensis and suggest this approach could be applied to evaluate the quality of other herbal medicines. HIGHLIGHTS: The fingerprints of Atractylodis rhizoma were organically combined with network pharmacology to further clarify its criteria for quality control.

Phytochemical profile and biological activities of the essential oils in the aerial part and root of Saposhnikovia divaricata.

The dried root of Saposhnikovia divaricata (Turcz.) Schischk. is popular as a good medicinal material, however the abundant aerial part is often discarded, which caused the waste of resources. In order to exploit resources, the essential oils of the plant aerial part and root were extracted, separately called as VOA and VOR, their chemicals were identified. The tumor necrosis factor-α, interleukin-6, nitric oxide and interleukin-1ß were detected to evaluate the oils anti-inflammatory activities. Then, the oils free radical scavenging rates were measured with DPPH, ABTS and hydroxyl free radical. The oils antitumor activities were evaluated with HeLa and HCT-8 cancer cell lines. The results showed the concentrations of VOA and VOR were separately 0.261% and 0.475%. Seventeen components of VOA were identified, accounting for 80.48% of VOA, including phytol, spathulenol, phytone, 4(15),5,10(14)-Germacratrien-1-ol, neophytadiene, etc. Seven components of VOR were determined, representing 90.73% of VOR, consisted of panaxynol, ß-bisabolene, etc. VOA and VOR significantly inhibited the secretion of nitric oxide, interleukin-1ß, interleukin-6 and tumor necrosis factor-α, effectively scavenged the DPPH, ABTS and hydroxyl free radicals, and showed significant antiproliferative activity against HeLa and HCT-8. The two oils presented important biological activity, which provided a hopeful utilized basis, and helped to reduce the waste of the aerial non-medicinal resources of S. divaricata.

Essential oil from Sabina chinensis leaves: A promising green control agent against Fusarium sp.

Sabina chinensis is a woody plant with important ecological functions in different regions of China, but its essential oils (EO) against plant pathogenic fungi remain largely undetermined. The purpose of our study was to assess the chemical composition and antifungal activity of S. chinensis EO based on optimization of the extraction process. In this study, an actionable and effective model with the experimental results and identified optimum conditions (crushing degree of 20 mesh, liquid-solid ratio of 10.1:1, immersion time of 9.1 h) was established successfully to achieve an extraction yield of 0.54%, which was basically consistent with the theoretical value. A total of 26 compounds were identified using headspace gas chromatography-mass spectrometry (GC-MS) and showed that the major constituent was ß-phellandrene (26.64-39.26%), followed by terpinen-4-ol (6.53-11.89%), bornyl acetate (6.13-10.53%), etc. For Petri plate assays, our experiments found for the first time that S. chinensis EO revealed high and long-term antifungal activity against the tested strains, including Fusarium oxysporum and Fusarium incarnatum, at EC50 values of 1.42 and 1.15 µL/mL, which especially reached approximately 76% and 90% growth inhibition at a dose of 0.2 µL/mL, respectively. Furthermore, the antifungal activity of EO from different harvest periods showed remarkable variation. The orthogonal partial least-squares discriminant analysis (OPLS-DA) method revealed 11 metabolites with chemical marker components, and 5 of its potential antifungal activities, terpinen-4-ol, α-terpineol, α-elemol, γ-eudesmol, and bornyl acetate, were strongly correlated with the mycelial inhibition rate. In total, this study explored the antifungal activity of EO against root rot fungus as a potential fungicide and provided valuable information into developing potential products from natural agents.

[Chemical pattern recognition of Atractylodes chinensis from different producing areas and establishment of quantitative analysis of multi-components by single marker (QAMS) method for four components].

This study established the fingerprint and combined it with chemical pattern recognition to evaluate the quality of Atractylodes chinensis samples from different producing areas and then employed the quantitative analysis of multi-components by single marker(QAMS) method to verify the feasibility and applicability of the established method in the quality evaluation of A. chinensis. The fingerprints of A. chinensis samples were constructed via high performance liquid chromatography(HPLC) to evaluate the inter-batch consistency. With the quality control component atractylodin as the internal reference, the relative correction factors(RCFs) were established for atractylenolide Ⅰ, atractylenolide Ⅲ, and ß-eudesmol and the content of the four components was calculated. The external standard method was used to verify the accuracy of QAMS method. The quality of A. chinensis was further evaluated by similarity analysis, clustering analysis, and principal component analysis. The fingerprints of 13 batches of samples were calibrated with 21 common peaks, and 4 common peaks were identified with the similarities all above 0.9. The RCFs established with atractylodin as the internal reference represented good reproducibility under different experimental conditions. Specifically, the RCFs of atractylenolide Ⅰ, atractylenolide Ⅲ, and ß-eudesmol in A. chinensis were 2.091, 4.253, and 6.010, respectively. QAMS and ESM showed no significant difference in the results, indicating that the QAMS method established in this study was stable and reliable. Thus, HPLC fingerprint combined with QAMS can be used for the quality evaluation of A. chinensis, providing a basis for comprehensive and rapid quality evaluation of A. chinensis.

The cultivable endophytic fungal community of Scutellaria baicalensis: diversity and relevance to flavonoid production by the host.

Scutellaria baicalensis (SB), a traditional Chinese medicinal plant, is widely used because of its important pharmacological activities. However, the endophytic fungi that promote flavonoid accumulation in SB remain unclear. Therefore, we analyzed the endophytic fungal community of SB and screened the endophytic fungi that might promote flavonoid synthesis in SB. ITS1/ITS4Blast was used to identify the endophytic fungi in SB. In total, 687 strains were identified in 57 genera. The dominant genus in the leaves and stems was Alternaria and that in the roots was Fusarium. Alternaria was the dominant genus in SB collected from all sites and in wild and cultivated SB. Alpha diversity indexes indicated more abundant endophytic fungi in samples from Chengde, the genuine producing area of SB, than in those from other sites. Beta diversity index analysis indicated that SB plants with closer geographical relationships showed more similar endophytic fungal community profiles. Spearman correlation analysis revealed that baicalin, wogonoside, wogonin, and oroxylin A contents were significantly correlated with the relative abundance of Alternaria. Overall, the results indicate the importance of geographical factors in influencing the endophytic fungal community of SB and suggest that the presence of Alternaria spp. might contribute to flavonoid synthesis in SB.

Differences in gene expression and endophytic bacterial diversity in Atractylodes macrocephala Koidz. rhizomes from different growth years.

Atractylodes macrocephala Koidz. (AMK) is widely used in traditional Chinese medicine owing to its pharmacological activity. Here, we aimed to characterize the differentially expressed genes (DEGs) of one- and three-year growth (OYG and TYG) rhizomes of AMK, combined with endophytic bacterial diversity analysis using high-throughput RNA sequencing. A total of 114 572 unigenes were annotated using six public databases. In all, 3570 DEGs revealed a clear difference, of which 936 and 2634 genes were upregulated and downregulated, respectively. The results of KEGG pathway analysis indicated that DEGs corresponding to terpenoid synthesis gene were downregulated in TYG rhizomes. In addition, 414 424 sequences corresponding to the 16S rRNA gene were divided into 1267 operational taxonomic units (OTUs). Moreover, the diversity of endophytic bacteria changed with species in the OYG (773) and TYG (1201) rhizomes at the OTU level, and Proteobacteria, Actinobacteria, and Bacteroidetes were the dominant phyla. A comparison of species differences among different growth years revealed that some species were significantly different, such as Actinomycetes, Variovorax, and Cloacibacterium. Interestingly, the decrease in the function-related metabolism of terpenoids and polyketides was correlated with the low expression of terpene synthesis genes in TYG rhizomes, as assessed using PICRUSt2. These data provide a scientific basis for elucidating the mechanisms underlying metabolite accumulation and endophytic bacterial diversity in relation to the growth years in AMK.

Advances and challenges in medicinal plant breeding.

Large-scale cultivation of medicinal plants is the most rapid and effective means of addressing the disparity between the supply and demand of medicinal plants. To achieve this scale of production, breeding studies are necessary for further development of medicinal plant cultivation. Although advances have been made in the breeding of some medicinal plants, a number of challenges remain, owing to the particularity and complexity in determining the breeding target. Additionally, there are limitations associated with research on traditional and modern breeding methods for medicinal plants. In this review, we summarize and analyze the selection strategies for breeding direction and breeding models, and emphasize the importance of breeding research in promoting the breeding of medicinal plants.

[Research progress on effect factors of secondary metabolites content in callus].

Secondary metabolites are the result of that plant interaction with biological and non-biological factors in the long-term evolution process, and play an important role in plant growth, development and physiology. The effective components of medicinal plant are usually the secondary metabolites in plant cells, and the synthesis of them are affected by a variety of factors, such as environmental impact. Acquirement of the secondary metabolites via callus culture has the advantage of low cost and less environmental impact. The synthesis and accumulation of medicinal plant secondary metabolites are not only controlled by light, temperature and pH, but also infected by germplasm, plant growth regulator and elicitor. This article presents a review of the influencing factors, and provides a basis for further study and development.

[Tissue culture of medicinal plant and abscisic acid].

Abscisic acid (ABA) plays a key role in many physiological processes of plants, and it was also applied to fields of medicinal plant biotechnology. The article presents a review of some recent application of ABA in enhancing the production of secondary metabolites of medicinal plants, improving the in vitro conservation in medicinal plant tissue culture system.

[Effects of light intensities endogenous hormones of Bletilla striata during acclimatization].

OBJECTIVE: The effect of light intensities on the endogenous hormones of Bletilla striata during seedling acclimatization was studied in order to explain the mechanism and provide basic data for conservation and cultivation of this wild medicinal species. METHOD: The samples was treated with three photosynthetic photon flux densities: 3 000, 6 000, 12 000 lx during the acclimatization stage to study the hormone dynamic changes of IAA, ABA, GA3. RESULT: Endogenous IAA concentration was declined in all treatments and the lowest level in all treatments was the middle light intensity. A sharp increase of endogenous ABA concentration in a short period, the concentration was increased by 380.2% in middle light (320.8 ng x g(-1)). Endogenous GA3 concentration was declined especially in the high light treatment. At 10 days of acclimatization the GA3 concentration was decreased by 52.2% in the high light (473.6 ng x g(-1)). RESULT: Endogenous hormones concentration could be rapidly changed by the light, and endogenous ABA concentration could be sharply increased when acclimatization in middle light intensities.