The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Xiaojun Yang - One of the best experts on this subject based on the ideXlab platform.
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transcriptomic analysis reveals distinct resistant response by Physcion and chrysophanol against cucumber powdery mildew
PeerJ, 2016Co-Authors: Shilin Tian, Xiaojun Yang, Xin Wang, Yuhai GuoAbstract:Physcion and chrysophanol induce defense responses against powdery mildew in cucumbers. The combination of these two compounds has synergistic interaction against the disease. We performed RNA-seq on cucumber leaf samples treated with Physcion and chrysophanol alone and with their combination. We generated 17.6 Gb of high-quality sequencing data (∼2 Gb per sample) and catalogued the expressions profiles of 12,293 annotated cucumber genes in each sample. We identified numerous differentially expressed genes that exhibited distinct expression patterns among the three treatments. The gene expression patterns of the Chr and Phy treatments were more similar to each other than to the Phy × Chr treatment. The Phy × Chr treatment induced the highest number of differentially expressed genes. This dramatic transcriptional change after Phy × Chr treatment leaves reflects that Physcion combined with chrysophanol treatment was most closely associated with induction of disease resistance. The analysis showed that the combination treatment caused expression changes of numerous defense-related genes. These genes have known or potential roles in structural, chemical and signaling defense responses and were enriched in functional gene categories potentially responsible for cucumber resistance. These results clearly demonstrated that disease resistance in cucumber leaves was significantly influenced by the combined Physcion and chrysophanol treatment. Thus, Physcion and chrysophanol are appealing candidates for further investigation of the gene expression and associated regulatory mechanisms related to the defense response.
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Physcion a natural anthraquinone derivative enhances the gene expression of leaf specific thionin of barley against blumeria graminis
Pest Management Science, 2010Co-Authors: Xiaojun Yang, Fansong Zeng, Lijun YangAbstract:BACKGROUND: Physcion is a key active ingredient of the ethanol extract from roots of Chinese rhubarb (Rheum officinale Baill.) that has been commercialised in China for controlling powdery mildews. The biological mechanism of action of Physcion against the barley powdery mildew pathogen was studied using bioassay and microarray methods. RESULTS: Bioassay indicated that Physcion did not directly affect conidial germination of Blumeria graminis Speer f. sp. hordei Marchal, but significantly inhibited conidial germination in vivo. Challenge inoculation indicated that Physcion induced localised resistance rather than systemic resistance against powdery mildew. Gene expression profiling of Physcion-treated barley leaves detected four upregulated and five downregulated genes (ratio ≥ 2.0 and P-value < 0.05) by using an Affymetrix Barley GeneChip. The five upregulated probe sequences blasted to the same barley leaf-specific thionin gene, with significant changes varying from 4.26 to 19.91-fold. All downregulated genes were defence-related, linked to peroxidase, oxalate oxidase, bsi1 protein and a pathogenesis-related protein. These changes varied from − 2.34 to − 2.96. Quantitative real-time PCR data confirmed that Physcion enhanced the gene expression of leaf-specific thionin of barley. CONCLUSION: Results indicated that Physcion controls powdery mildew mainly through changing the expression of defence-related genes, and especially enhancing expression of leaf-specific thionin in barley leaves. Copyright © 2010 Society of Chemical Industry
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effects of Physcion a natural anthraquinone derivative on the infection process of blumeria graminis on wheat
Canadian Journal of Plant Pathology-revue Canadienne De Phytopathologie, 2008Co-Authors: Xiaojun Yang, Lijun YangAbstract:Physcion is one of the important active ingredients of ethanol extract from the roots of Chinese rhubarb (Rheum officinale) for controlling powdery mildew. A histological investigation indicated that this compound affected Blumeria graminis in vivo by inhibiting the germination of conidia, by increasing the rate of appressorium deformation before the pathogen infected the cells of wheat (Triticum aestivum), and by reducing the length of haustoria and the number of secondary haustoria after infection.
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Distribution of Baseline Sensitivities to Natural Product Physcion Among Isolates of Sphaerotheca fuliginea and Pseudoperonospora cubensis.
Plant Disease, 2008Co-Authors: Xiaojun Yang, L. J. Yang, F. S. Zeng, L. B. Xiang, S. N. WangAbstract:ABSTRACT The ethanol extract from rhubarb was commercialized in China (Veguard, Physcion, 5 g/liter AS) for control of cucumber powdery mildew (Sphaerotheca fuliginea) and cucumber downy mildew (Pseudoperonospora cubensis). To provide the basic data for the risk assessment of resistance to this product, Physcion was selected to represent the active ingredients to establish baseline sensitivity of powdery mildew and downy mildew populations. For powdery mildew, 262 isolates of S. fuliginea from nine regions and, for downy mildew populations, 116 isolates of P. cubensis from six regions were collected in China during 2004 and 2005 and tested for sensitivity. In addition, the sensitivity of a powdery mildew isolate was monitored for 15 asexual generations under selection pressure with Physcion. The results showed that there was no significant difference among regions in the frequency distribution of baseline sensitivity to this ingredient for either cucumber powdery mildew isolates or cucumber downy mildew i...
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Synergistic interaction of Physcion and chrysophanol on plant powdery mildew
Pest Management Science, 2007Co-Authors: Xiaojun Yang, Lijun Yang, Shaonan WangAbstract:The extract of the plant Rheum officinale Baill, mainly containing the anthraquinones Physcion and chrysophanol, is highly active against plant powdery mildew. Experiments were conducted in the laboratory and greenhouse to determine the interaction of the two compounds on cucumber powdery mildew [Sphaerotheca fuliginea (Schlecht.) Poll] and on wheat powdery mildew [Blumeria graminis (DC.) Speer f. sp. tritici Marchal]. Physcion was much more bioactive than chrysophanol against these powdery mildews. There was a significant synergistic interaction between the two compounds on the diseases when the ratios of Physcion to chrysophanol ranged from 1:9 to 5:5. The synergistic degree increased with increase in the chrysophanol proportion in the combination. The findings indicate that, in order to ensure constant efficacy of the extract on the disease, both the contents and the proportion of the main active ingredients Physcion and chrysophanol have to be determined.
Markus Riederer - One of the best experts on this subject based on the ideXlab platform.
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direct effects of Physcion chrysophanol emodin and pachybasin on germination and appressorium formation of the barley hordeum vulgare l powdery mildew fungus blumeria graminis f sp hordei dc speer
Journal of Agricultural and Food Chemistry, 2018Co-Authors: Ulrich Hildebrandt, Alexander Marsell, Markus RiedererAbstract:Several anthraquinone derivatives are active components of fungicidal formulations particularly effective against powdery mildew fungi. The antimildew effect of compounds such as Physcion and chrysophanol is largely attributed to host plant defense induction. However, so far a direct fungistatic/fungicidal effect of anthraquinone derivatives on powdery mildew fungi has not been unequivocally demonstrated. By applying a Formvar-based in vitro system we demonstrate a direct, dose-dependent effect of Physcion, chrysophanol, emodin, and pachybasin on conidial germination and appressorium formation of Blumeria graminis f. sp. hordei (DC.) Speer, the causative agent of barley (Hordeum vulgare L.) powdery mildew. Physcion was the most effective among the tested compounds. At higher doses, Physcion mainly inhibited conidial germination. At lower rates, however, a distinct interference with appressorium formation became discernible. Physcion and others may act by modulating both the infection capacity of the powde...
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Direct Effects of Physcion, Chrysophanol, Emodin, and Pachybasin on Germination and Appressorium Formation of the Barley (Hordeum vulgare L.) Powdery Mildew Fungus Blumeria graminis f. sp. hordei (DC.) Speer
2018Co-Authors: Ulrich Hildebrandt, Alexander Marsell, Markus RiedererAbstract:Several anthraquinone derivatives are active components of fungicidal formulations particularly effective against powdery mildew fungi. The antimildew effect of compounds such as Physcion and chrysophanol is largely attributed to host plant defense induction. However, so far a direct fungistatic/fungicidal effect of anthraquinone derivatives on powdery mildew fungi has not been unequivocally demonstrated. By applying a Formvar-based in vitro system we demonstrate a direct, dose-dependent effect of Physcion, chrysophanol, emodin, and pachybasin on conidial germination and appressorium formation of Blumeria graminis f. sp. hordei (DC.) Speer, the causative agent of barley (Hordeum vulgare L.) powdery mildew. Physcion was the most effective among the tested compounds. At higher doses, Physcion mainly inhibited conidial germination. At lower rates, however, a distinct interference with appressorium formation became discernible. Physcion and others may act by modulating both the infection capacity of the powdery mildew pathogen and host plant defense. Our results suggest a specific arrangement of substituents at the anthraquinone backbone structure being crucial for the direct antimildew effect
Hongying Zhang - One of the best experts on this subject based on the ideXlab platform.
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Physcion a naturally occurring anthraquinone derivative induces apoptosis and autophagy in human nasopharyngeal carcinoma
Acta Pharmacologica Sinica, 2016Co-Authors: Mingjie Pang, Zhun Yang, Xinglin Zhang, Zhaofang Liu, Jun Fan, Hongying ZhangAbstract:Aim: Physcion is a major bioactive ingredient in the traditional Chinese medicine Radix et Rhizoma Rhei, which has an anthraquinone chemical structure and exhibits a variety of pharmacological activities including laxative, hepatoprotective, anti-inflammatory, antimicrobial and anti-proliferative effects. In this study we investigated the effect of Physcion on human nasopharyngeal carcinoma in vitro and in vivo, as well as the mechanisms underlying the anti-tumor action. Methods: The nasopharyngeal carcinoma cell line CNE2 was treated with Physcion, and cell viability was detected using MTT and colony formation assays. Flow cytometry was used to assess the cell cycle arrest, mitochondrial membrane potential loss, apoptosis, autophagy and intracellular ROS generation. Apoptotic cell death was also confirmed by a TUNEL assay. The expression of target or marker molecules was determined using Western blotting. The activity of caspase-3, 8, and 9 was detected with an ELISA kit. A xenograft murine model was used to evaluate the in vivo anti-tumor action of Physcion, the mice were administered Physcion (10, 20 mg·kg -1 ·d -1 , ip) for 30 d. Results: Treatment with Physcion (5, 10, and 20 μmol/L) dose-dependently suppressed the cell viability and colony formation in CNE2 cells. Physcion (10 and 20 μmol/L) dose-dependently blocked cell cycle progression at G 1 phase and induced both caspase-dependent apoptosis and autophagy in CNE2 cells. Furthermore, Physcion treatment induced excessive ROS generation in CNE2 cells, and subsequently disrupted the miR-27a/ZBTB10 axis, resulting in repression of the transcription factor Sp1 that was involved in Physcioninduced apoptosis and autophagy. Moreover, Physcion-induced autophagy acted as a pro-apoptotic factor, and possibly contributed to Physcion-induced apoptosis. In the xenograft murine model, administration of Physcion dose-dependently suppressed the tumor growth without affecting the body weight. Furthermore, the anti-tumor effects of Physcion were correlated with downregulation of Sp1 and suppression of miR-27a in the tumor tissues. Conclusion: Physcion induces apoptosis and autophagy in human nasopharyngeal carcinoma by targeting Sp1, which was mediated by ROS/miR-27a/ZBTB10 signaling. The results suggest that Physcion is a promising candidate for the treatment of human nasopharyngeal carcinoma.
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Physcion a naturally occurring anthraquinone derivative induces apoptosis and autophagy in human nasopharyngeal carcinoma
Acta Pharmacologica Sinica, 2016Co-Authors: Mingjie Pang, Zhun Yang, Xinglin Zhang, Zhaofang Liu, Jun Fan, Hongying ZhangAbstract:Physcion is a major bioactive ingredient in the traditional Chinese medicine Radix et Rhizoma Rhei, which has an anthraquinone chemical structure and exhibits a variety of pharmacological activities including laxative, hepatoprotective, anti-inflammatory, anti-microbial and anti-proliferative effects. In this study we investigated the effect of Physcion on human nasopharyngeal carcinoma in vitro and in vivo, as well as the mechanisms underlying the anti-tumor action. The nasopharyngeal carcinoma cell line CNE2 was treated with Physcion, and cell viability was detected using MTT and colony formation assays. Flow cytometry was used to assess the cell cycle arrest, mitochondrial membrane potential loss, apoptosis, autophagy and intracellular ROS generation. Apoptotic cell death was also confirmed by a TUNEL assay. The expression of target or marker molecules was determined using Western blotting. The activity of caspase-3, 8, and 9 was detected with an ELISA kit. A xenograft murine model was used to evaluate the in vivo anti-tumor action of Physcion, the mice were administered Physcion (10, 20 mg·kg−1·d−1, ip) for 30 d. Treatment with Physcion (5, 10, and 20 μmol/L) dose-dependently suppressed the cell viability and colony formation in CNE2 cells. Physcion (10 and 20 μmol/L) dose-dependently blocked cell cycle progression at G1 phase and induced both caspase-dependent apoptosis and autophagy in CNE2 cells. Furthermore, Physcion treatment induced excessive ROS generation in CNE2 cells, and subsequently disrupted the miR-27a/ZBTB10 axis, resulting in repression of the transcription factor Sp1 that was involved in Physcion-induced apoptosis and autophagy. Moreover, Physcion-induced autophagy acted as a pro-apoptotic factor, and possibly contributed to Physcion-induced apoptosis. In the xenograft murine model, administration of Physcion dose-dependently suppressed the tumor growth without affecting the body weight. Furthermore, the anti-tumor effects of Physcion were correlated with downregulation of Sp1 and suppression of miR-27a in the tumor tissues. Physcion induces apoptosis and autophagy in human nasopharyngeal carcinoma by targeting Sp1, which was mediated by ROS/miR-27a/ZBTB10 signaling. The results suggest that Physcion is a promising candidate for the treatment of human nasopharyngeal carcinoma.
Junzeng Zhang - One of the best experts on this subject based on the ideXlab platform.
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Quality Assessment of Japanese Knotweed (Fallopia japonica) Grown on Prince Edward Island as a Source of Resveratrol
Journal of agricultural and food chemistry, 2013Co-Authors: Huaguo Chen, Xin Zhou, Glen Kelly, Tina Tuck, Alain Cuerrier, Junzeng ZhangAbstract:Japanese knotweed (Fallopia japonica , also known as Polygonum cuspidatum) is a common invasive plant species on Prince Edward Island (PEI), Canada, whereas it has been used in Chinese medicine and more recently as a raw material for extracting resveratrol. This paper reports on the quantification of resveratrol, polydatin, emodin, and Physcion in roots, stems, and leaves of Japanese knotweed samples from PEI and British Columbia (BC), Canada, and nine provinces of China, by ultraperformance liquid chromatography (UPLC). The results showed that the root contains a much higher level of resveratrol than the stem and leaf, and it is accumulated in its highest level in October. PEI-grown knotweed contains similar levels of resveratrol and polydatin compared to Chinese samples collected in the month of October, but the contents of the other anthraquinones (emodin and Physcion) are different. As such, Japanese knotweed grown in PEI could be a commercially viable source of raw material for resveratrol production; however, caution has to be taken in harvesting the right plant species.
Lijun Yang - One of the best experts on this subject based on the ideXlab platform.
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bionic fungicide Physcion controls gray mold in tomato possible modes of action
Journal of General Plant Pathology, 2019Co-Authors: Libo Xiang, Lijun Yang, Minfeng Xue, Shuangjun GongAbstract:In this investigation of the efficacy of the natural product Physcion for the control of gray mold of tomato in the field and possible modes of action, Physcion was significantly less effective in in vitro antifungal tests than synthetic fungicides pyrimethanil and boscalid. However, in greenhouse tests, Physcion dramatically reduced the severity of gray mold on tomato plants. We further found elevated activity of several enzymes associated with the synthesis of phenolic compounds and plant defense reactions, including phenylalanine ammonia-lyase, peroxidase, and polyphenol oxidase. Physcion also significantly increased plant growth, indicating that it can also act as a growth promoter in tomato. The results from two consecutive years of field trials revealed that the application of Physcion at a rate of 9 g a.i./ha reduced disease incidence between 63.44 and 69.79%, comparable to the fungicide pyrimethanil. Together, these results indicate that although Physcion had little direct effect on the growth of B. cinerea, it increased tomato performance by stimulating an endogenous plant defense response and acting as a growth promoter. The study therefore provides strong evidence that Physcion provides an alternative treatment for the management of gray mold in organic and low input tomato production and in traditional integrated pest management programs.
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Physcion a natural anthraquinone derivative enhances the gene expression of leaf specific thionin of barley against blumeria graminis
Pest Management Science, 2010Co-Authors: Xiaojun Yang, Fansong Zeng, Lijun YangAbstract:BACKGROUND: Physcion is a key active ingredient of the ethanol extract from roots of Chinese rhubarb (Rheum officinale Baill.) that has been commercialised in China for controlling powdery mildews. The biological mechanism of action of Physcion against the barley powdery mildew pathogen was studied using bioassay and microarray methods. RESULTS: Bioassay indicated that Physcion did not directly affect conidial germination of Blumeria graminis Speer f. sp. hordei Marchal, but significantly inhibited conidial germination in vivo. Challenge inoculation indicated that Physcion induced localised resistance rather than systemic resistance against powdery mildew. Gene expression profiling of Physcion-treated barley leaves detected four upregulated and five downregulated genes (ratio ≥ 2.0 and P-value < 0.05) by using an Affymetrix Barley GeneChip. The five upregulated probe sequences blasted to the same barley leaf-specific thionin gene, with significant changes varying from 4.26 to 19.91-fold. All downregulated genes were defence-related, linked to peroxidase, oxalate oxidase, bsi1 protein and a pathogenesis-related protein. These changes varied from − 2.34 to − 2.96. Quantitative real-time PCR data confirmed that Physcion enhanced the gene expression of leaf-specific thionin of barley. CONCLUSION: Results indicated that Physcion controls powdery mildew mainly through changing the expression of defence-related genes, and especially enhancing expression of leaf-specific thionin in barley leaves. Copyright © 2010 Society of Chemical Industry
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effects of Physcion a natural anthraquinone derivative on the infection process of blumeria graminis on wheat
Canadian Journal of Plant Pathology-revue Canadienne De Phytopathologie, 2008Co-Authors: Xiaojun Yang, Lijun YangAbstract:Physcion is one of the important active ingredients of ethanol extract from the roots of Chinese rhubarb (Rheum officinale) for controlling powdery mildew. A histological investigation indicated that this compound affected Blumeria graminis in vivo by inhibiting the germination of conidia, by increasing the rate of appressorium deformation before the pathogen infected the cells of wheat (Triticum aestivum), and by reducing the length of haustoria and the number of secondary haustoria after infection.
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Synergistic interaction of Physcion and chrysophanol on plant powdery mildew
Pest Management Science, 2007Co-Authors: Xiaojun Yang, Lijun Yang, Shaonan WangAbstract:The extract of the plant Rheum officinale Baill, mainly containing the anthraquinones Physcion and chrysophanol, is highly active against plant powdery mildew. Experiments were conducted in the laboratory and greenhouse to determine the interaction of the two compounds on cucumber powdery mildew [Sphaerotheca fuliginea (Schlecht.) Poll] and on wheat powdery mildew [Blumeria graminis (DC.) Speer f. sp. tritici Marchal]. Physcion was much more bioactive than chrysophanol against these powdery mildews. There was a significant synergistic interaction between the two compounds on the diseases when the ratios of Physcion to chrysophanol ranged from 1:9 to 5:5. The synergistic degree increased with increase in the chrysophanol proportion in the combination. The findings indicate that, in order to ensure constant efficacy of the extract on the disease, both the contents and the proportion of the main active ingredients Physcion and chrysophanol have to be determined.
