Apocynum Venetum Research Articles

Chromosome-scale genome assembly of Apocynum pictum, a drought-tolerant medicinal plant from the Tarim Basin.

Apocynum pictum Schrenk is a semishrub of the Apocynaceae family with a wide distribution throughout the Tarim Basin that holds significant ecological, medicinal, and economic values. Here, we report the assembly of its chromosome-level reference genome using Nanopore long-read, Illumina HiSeq paired-end, and high-throughput chromosome conformation capture sequencing. The final assembly is 225.32 Mb in length with a scaffold N50 of 19.64 Mb. It contains 23,147 protein-coding genes across 11 chromosomes, 21,148 of which (91.36%) have protein functional annotations. Comparative genomics analysis revealed that A. pictum diverged from the closely related species Apocynum venetum approximately 2.2 million years ago and has not undergone additional polyploidizations after the core eudicot WGT-γ event. Karyotype evolution analysis was used to characterize interchromosomal rearrangements in representative Apocynaceae species and revealed that several A. pictum chromosomes were derived entirely from single chromosomes of the ancestral eudicot karyotype. Finally, we identified 50 members of the well-known stress-responsive WRKY transcription factor family and used transcriptomic data to document changes in their expression at 2 stages of drought stress, identifying a number of promising candidate genes. Overall, this study provides high-quality genomic resources for evolutionary and comparative genomics of the Apocynaceae, as well as initial molecular insights into the drought adaptation of this valuable desert plant.

Harnessing the microbial interactions from Apocynum venetum phyllosphere for natural product discovery

Natural products (NPs) afforded by living-beings, especially by microscopic species, represent invaluable and indispensable reservoirs for drug leads in clinical practice. With the rapid advancement in sequencing technology and bioinformatics, the ever-increasing number of microbial biosynthetic gene clusters (BGCs) were decrypted, while a great deal of BGCs remain cryptic or inactive under standard laboratory culture conditions. Addressing this dilemma requires innovative tactics to awaken quiescence of BGCs by releasing the potential of microbial secondary metabolism for mining novel NPs. In this study, a universal strategy was proposed to induce the expression of silent BGCs by leveraging the dynamic interactions among coexisting microbial neighbors within a microbiota. This approach involves the deconstruction/reconstruction of binary interactions among the coexisting neighbors to create a pipeline for BGCs arousing. Coupled with the acquisition of 2,760 microbial individuals from the Apocynum venetum (Luobuma, LBM) phyllosphere in a successive dilution procedure, 44 culturable isolates were screened using binary interaction, in which 12.6% pairs demonstrated potent mutual interacting effects. Furthermore, after selecting the most four promising isolates, a full-scale metabolic inspection was conducted, in which 25.3% of the interacting pairs showcased significant metabolomic variations with de-cryptic activities. Notably, with the aid of visualization of IMS technology, one of the physiologically functional entities, the bactericidal agent resistomycin, was elucidated from the core interacting pair between the co-culture of the Streptomyces sp. LBM_605 and the Rhodococcus sp. LBM_791. This study highlights the intrinsic interactions among coexisting microorganisms within a phyllosphere microbiota as novel avenues for exploring and harnessing NPs.

Extraction of polyphenols from Apocynum venetum leaves using customized deep eutectic solvents: Process optimization and antioxidant evaluation

To encourage the commercial utilization of A. venetum polyphenols as bio-colorant on textile, five different combinations of deep eutectic solvents (DESs) were evaluated using a single-factor approach and the extraction of polyphenols from A. venetum leaves by ultrasound-assisted DESs was optimized. At the same time, the antioxidant activity of polyphenols prepared were investigated. The DESs composed of choline chloride and glycerol with a molar ratio of 1:2 and a water content of 20 % showed higher extraction performance than other DESs and traditional solvents (water, 60 % ethanol and 60 % methanol). With the most effective solvent the maximum yield 8.24 % of polyphenols was obtained under the optimal extraction conditions were as follows: the ratio of liquid volume (mL) to solid mass (g) is 49:1, extraction temperature of 77 ℃, and extraction time of 55 min. In addition, the polyphenols that have been separated and purified from the DESs extract exhibited antioxidant activities in three kinds of assays including 2,2-diphenyl-1-picrylhydrazyl stable free radical (DPPH), 2,2’-azino-bis-(3-ethylbenzothiazoline-6-sulfonic) acid free radicals (ABTS) and hydroxyl radical (•OH) scavenging activity. Therefore, this paper demonstrates that DESs are effective and environmentally friendly solvents extraction of antioxidant polyphenols pigments from the leaves of A. venetum.

Polyphenol-Rich Extract of Apocynum venetum L. Leaves Protects Human Retinal Pigment Epithelial Cells against High Glucose-Induced Damage through Polyol Pathway and Autophagy.

Diabetic retinopathy (DR) is a specific microvascular problem of diabetes, which is mainly caused by hyperglycemia and may lead to rapid vision loss. Dietary polyphenols have been reported to decrease the risk of DR. Apocynum venetum L. leaves are rich in polyphenolic compounds and are popular worldwide for their health benefits as a national tea drink. Building on previous findings of antioxidant activity and aldose reductase inhibition of A. venetum, this study investigated the chemical composition of polyphenol-rich extract of A. venetum leaves (AVL) and its protective mechanism on ARPE-19 cells in hyperglycemia. Ninety-three compounds were identified from AVL by LC-MS/MS, including sixty-eight flavonoids, twenty-one organic acids, and four coumarins. AVL regulated the polyol pathway by decreasing the expression of aldose reductase and the content of sorbitol, enhancing the Na+K+-ATPase activity, and weakening intracellular oxidative stress effectively; it also could regulate the expression of autophagy-related proteins via the AMPK/mTOR/ULK1 signaling pathway to maintain intracellular homeostasis. AVL could restore the polyol pathway, inhibit oxidative stress, and maintain intracellular autophagy to protect cellular morphology and improve DR. The study reveals the phytochemical composition and protective mechanisms of AVL against DR, which could be developed as a functional food and/or candidate pharmaceutical, aiming for retina protection in diabetic retinopathy.

Distribution characteristics of selenium and influencing factors in the plant–soil system of an arid oasis

A total of 323 topsoil samples, 63 profile soil samples, and 55 plant root samples were collected from an oasis area on the eastern margin of the Tarim Basin in China and the selenium content and other physical and chemical indicators were analyzed. The results showed that the average selenium content in the surface soil was 0.15 mg/kg, which was lower than the national background value, and only about 4% of the surveyed land area was classified as rich in selenium. The vertical distribution of selenium was characterized by surface accumulation. The organic carbon and clay content were positively correlated and the pH levels negatively correlated with the selenium content. Soil type had little effect on selenium content, though the selenium levels in Anthrosols and Gleysols were relatively high. The selenium content for cultivated land and garden soil was higher than for other land use types. The enrichment of selenium in plant roots was highest for Apocynum venetum L., followed by Pulicaria dysenterica (L.). Bernh., Populus euphratica Olive, Tamarix chinensis Lour., Phragmites australis (Cav.) Trin. ex Steud, and Pyrus bretschneideri Rehder. Correlation analysis revealed that the enrichment of selenium in the soil was mainly controlled by supergenesis in conjunction with long-distance migration and deposition. Overall, this study provides useful information for the rational development and utilization of regional land resources.

Genome-wide identification and expression analysis of the PP2C gene family in Apocynum venetum and Apocynum hendersonii

BackgroundProtein phosphatase class 2 C (PP2C) is the largest protein phosphatase family in plants. Members of the PP2C gene family are involved in a variety of physiological pathways in plants, including the abscisic acid signalling pathway, the regulation of plant growth and development, etc., and are capable of responding to a wide range of biotic and abiotic stresses, and play an important role in plant growth, development, and response to stress. Apocynum is a perennial persistent herb, divided into Apocynum venetum and Apocynum hendersonii. It mainly grows in saline soil, deserts and other harsh environments, and is widely used in saline soil improvement, ecological restoration, textiles and medicine. A. hendersonii was found to be more tolerant to adverse conditions. The main purpose of this study was to investigate the PP2C gene family and its expression pattern under salt stress and to identify important candidate genes related to salt tolerance.ResultsIn this study, 68 AvPP2C genes and 68 AhPP2C genes were identified from the genomes of A. venetum and A. hendersonii, respectively. They were classified into 13 subgroups based on their phylogenetic relationships and were further analyzed for their subcellular locations, gene structures, conserved structural domains, and cis-acting elements. The results of qRT-PCR analyses of seven AvPP2C genes and seven AhPP2C genes proved that they differed significantly in gene expression under salt stress. It has been observed that the PP2C genes in A. venetum and A. hendersonii exhibit different expression patterns. Specifically, AvPP2C2, 6, 24, 27, 41 and AhPP2C2, 6, 24, 27, 42 have shown significant differences in expression under salt stress. This indicates that these genes may play a crucial role in the salt tolerance mechanism of A. venetum and A. hendersonii.ConclusionsIn this study, we conducted a genome-wide analysis of the AvPP2C and AhPP2C gene families in Apocynum, which provided a reference for further understanding the functional characteristics of these genes.

Prevention of cyclophosphamide-induced immune suppression by polysaccharides from Apocynum venetum flowers via enhancing immune response, reducing oxidative stress, and regulating gut microbiota in mice

IntroductionEmerging proof suggests that Apocynum venetum flowers polysaccharide (AVFP) has immunomodulatory effects in vitro. However, the action mechanism of AVFA is still unclear in vivo. The purpose of this study is to probe into the potential mechanism of AVFA in immunosuppressed mice by investigating organ index, cytokine levels, anti-oxidative stress capacity, transcriptomics, and gut microbiota.MethodsImmunocompromised mice induced by cyclophosphamide (CTX) were divided into six groups. The enzyme-labeled method, hematoxylin and eosin, transcriptomics, and high-throughput sequencing were used to detect the regulatory effects of AVFP on immunocompromised mice and the function of AVFP on the concentration of short-chain fatty acids (SCFAs) by high-performance liquid chromatography (HPLC) analysis. The Spearman correlation analysis was used to analyze the correlation between the intestinal microbiota and biochemical indexes.ResultsThe experimental results illustrated that AVFP has protective effects against CTX-induced immunosuppression in mice by prominently increasing the organ index and levels of anti-inflammatory factors in serum in addition to enhancing the antioxidant capacity of the liver. Meanwhile, it could also signally decrease the level of pro-inflammatory cytokines in serum, the activity of transaminase in serum, and the content of free radicals in the liver, and alleviate the spleen tissue damage induced by CTX. Transcriptomics results discovered that AVFP could play a role in immune regulation by participating in the NF-κB signaling pathway and regulating the immune-related genes Bcl3, Hp, Lbp, Cebpd, Gstp2, and Lcn2. Gut microbiota results illustrated that AVFP could increase the abundance of beneficial bacteria, reduce the abundance of harmful bacteria, and regulate the metabolic function of intestinal microorganisms while dramatically improving the content of SCFAs, modulating immune responses, and improving the host metabolism. The Spearman analysis further evaluated the association between intestinal microbiota and immune-related indicators.ConclusionThese findings demonstrated that AVFP could enhance the immune effects of the immunosuppressed mice and improve the body’s ability to resist oxidative stress.

Identification of core genes involved in the response of Apocynum venetum to salt stress based on transcriptome sequencing and WGCNA.

Apocynum venetum L. belongs to the Apocynaceae family and is a plant that is highly resistant to stress. It is important in the fields of ecology, feeding, industry and medicine. The molecular mechanism underlying salt tolerance has not been elucidated. In this study, RNA-seq based transcriptome sequencing of A. venetum leaves after 0, 2, 6, 12, 24 and 48 h of treatment with 300 mM NaCl was performed. We conducted a comprehensive analysis of the transcriptome expression profiles of A. venetum under salt stress using the WGCNA method and identified red, black, and brown as the core modules regulating the salt tolerance of A. venetum. A co-expression regulatory network was constructed to identify the core genes in the module according to the correlations between genes. The genes TRINITY_DN102_c0_g1 (serine carboxypeptidase), TRINITY_DN3073_c0_g1 (SOS signaling pathway) and TRINITY_DN6732_c0_g1 (heat shock transcription factor) in the red module were determined to be the core genes. Two core genes in the black module, TRINITY_DN9926_c0_g1 and TRINITY_DN7962_c0_g1, are pioneer candidate salt tolerance-associated genes in A. venetum. The genes in the brown module were mainly enriched in two pathways, namely photosynthesis and osmotic balance. Among them, the TRINITY_DN6321_c0_g2 and TRINITY_DN244_c0_g1 genes encode aquaporin, which is helpful for maintaining the cell water balance and plays a protective role in defending A. venetum under abiotic stress. Our findings contribute to the identification of core genes involved in the response of A. venetum to salt stress.

Chromosome-scale genome analysis of Apocynum venetum sheds light on Apocynum phylogenetics, bast fiber development, and flavonoid synthesis

Apocynum venetum is a natural bast fiber crop and officinal plant belonging to the family Apocynaceae. Here, a chromosome-scale genome sequence was assembled using the single molecule sequencing and Hi-C technology. The genome of A. venetum is 228.80 Mb in length and has an N50 of 3.43 Mb. Up to 99.82 % of the contigs were attached to 11 pseudo-chromosomes. A total of 21,327 protein-coding genes were annotated in A. venetum genome. Phylogenetic analysis revealed the evolutionary relationships among the genera of Apocynum, Calotropis, and Catharanthus. Genes involved in bast fiber synthesis were identified in A. venetum by comparing gene expression between stem barks in different locations on the main stem. Combined metabolomic and transcriptomic analysis revealed the coordinated changes in flavonoids and related genes under methyl jasmonate treatment, as well as the dynamic change patterns of the genes encoding enzymes in the biosynthesis of flavonoids. Co-expression network analysis identified key genes that regulate flavonoid biosynthesis, including CHI (Av02G001490 and Av02G016020), MYB (Av01G029390), and bHLH (Av08G002930). The genome assembly of A. venetum provides a useful data set for understanding the evolution of Apocynum, bast fiber synthesis, and flavonoid biosynthesis in A. venetum.

Joint Analysis of Small RNA and mRNA Sequencing Unveils miRNA-Mediated Regulatory Network in Response to Methyl Jasmonate in Apocynum venetum L.

Apocynum venetum L. is a natural fiber and medicinal plant species with significant economic value. Jasmonic acid is an endogenous growth regulatory substance present in higher plants that participate in plant growth, development, and defense. As important endogenous single-stranded RNA molecules, microRNA (miRNA) plays an important role in the post-transcriptional regulation of plant genes. A combination of miRNA and mRNA sequencing techniques was used to systematically identify the methyl jasmonate miRNAs and mRNAs in A. venetum. Up to 135 conserved and 26 species-specific miRNAs have been identified in A. venetum. These miRNAs mainly target genes that encode transcription factors and enzymes. The expression levels of 23 miRNAs, including miR398 and miR482, significantly changed after MeJA treatment. A total of 1778 genes were differentially expressed under MeJA treatment, of which 825 were upregulated and 953 were downregulated. The main biological processes enriched in these differentially expressed genes were redox balance, secondary metabolism, photosynthesis, and plant hormone signal transduction. Joint analysis of the miRNAs and mRNA revealed that MeJA-responsive miRNAs function by forming regulatory modules, including miR398-CSD, miR482-NBS-LRR, miR156-SPL10, and miR164-NAC056, which further regulate multiple biological processes, including redox balance, disease resistance, and morphogenesis in A. venetum. This study provides important information to understand the biological roles of miRNAs in A. venetum.

Transcriptomics-based identification of transcription factors in the halophyte Apocynum venetum L.

ABSTRACT The medicinal halophyte plant Apocynum venetum L. can tolerate high salt levels in the soil, which significantly affects its growth and development. To study the molecular mechanisms underlying its environmental adaptations, omics tools were employed. Apocynum venetum L. plants were subjected to varying levels of salt stress. The corresponding RNA of Apocyni Veneti Folium (AVF), the leaf of Apocynum venetum L., was sequenced using a de novo approach. Functional annotation and expression analysis were utilised to identify differentially expressed transcription factors (TFs). The classification of these TFs was further divided into different families, including AP2/ERF, bHLH, WRKY, and HSF. Under conditions of modest saline stress, the majority of TF genes exhibited a predilection for up-regulation, particularly bHLHs, which were discovered to be consistent with the build-up of flavonoid glycosides. In conjunction with previous proteomics and metabolomics findings, we have discovered that the gene bHLH35 is a potential candidate. This gene has shown changes at both the transcript and protein levels, indicating that it may play a crucial role in the biosynthesis of flavonoids under salt-induced environments. These findings provide invaluable information on the identification of key genes involved in elucidating flavonoid biosynthesis mechanisms and serve as a basis for the improvement of the halophyte AVF’s quality.

Evaluation of Suitable Reference Genes for Quantitative Real-Time PCR in Various Tissues of Apocynum venetum.

Apocynum venetum L. is an economically valuable plant with tolerance to drought and salinity. Its leaves are utilized in tea production and pharmaceuticals, while the stem bark serves as a high-quality fiber material. To gain insights into the gene expression patterns of A. venetum using quantitative real-time PCR (qRT-PCR), it is crucial to identify appropriate reference genes. This study selected nine candidate genes, including α-tubulin (TUA), β-tubulin (TUB), actin (ACT), cyclophilin (CYP), elongation factor-1α (EF-1α), the B family of regulatory subunits of protein phosphatase (PPP2R2, PPP2R3, and PPP2R5), and phosphoglycerate kinase (PGK), to determine the most appropriate reference genes in the leaf, stem, and root tissues of A. venetum. A comprehensive ranking by geNorm, NormFinder, BestKeeper, and RefFinder software and Venn diagrams was used to screen more stable reference genes in different tissues. The two most stable reference genes were CYP and TUA in leaves, PGK and PPP2R3 in stems, and TUA and EF-1α in roots, respectively. The relative expression values of the four genes involved in proline metabolism under polyethylene glycol treatment were used to validate the screened reference genes, and they exhibited highly stable expression levels. These findings represent the first set of stable reference genes for future gene expression studies in A. venetum. They significantly contribute to enhancing the accuracy and reliability of gene expression analyses in this economically important plant species.

Coupling of leaf economic and hydraulic traits of desert plants of different life forms in the Ebinur Lake Basin

The functional traits of leaves and their internal trade-offs have been the focus of ecologists as a powerful basis for revealing plant physiology and function, and ecological strategies. The consistency of the coupled relationship between leaf economic traits and hydraulic traits among trees, shrubs, and herbs in similar ecological environments has seldom been systematically explored. We explored coupling in desert plants of different life forms and their response to the soil environment in two tree species (Populus euphratica Oliv. and Haloxylon ammodendron (C. A. Mey.) Bunge)), the shrub species (Nitraria tangutorum Bobrov and Halimodendron halodendron (Pall.) Dum. Cours.), and herbaceous species (Alhagi sparsifolia Shap. and Apocynum venetum L.) in the transition zone of the desert in the Ebinur Lake Basin, Xinjiang, China. Leaf and soil samples were collected to determine plant leaf economic traits, hydraulic traits, and soil factors. Regarding leaf economic traits, trees had higher in leaf mass per area and leaf thickness (LT). The leaf nitrogen and phosphorus contents were higher in shurbs than those in trees and herbs. Regarding hydraulic traits, shrubs had higher palisade parenchyma thickness (PT) and vein density (VD), whereas herbs had higher stomatal length (SL), spongy parenchyma thickness (ST), and leaf water potential (Ψ). In herbs, SL, ST, and Ψ had advantages, whereas PT/ST was the lowest. This study revealed an association between leaf economic and hydraulic traits in plants of different life forms in a similar ecological environment and provides a scientific basis for plant conservation strategies and ecosystem services value assessment and use in arid zones.

Transcriptome analysis reveals how cadmium promotes root development and accumulates in Apocynum venetum, a promising plant for greening cadmium-contaminated soil

Cadmium (Cd) contamination poses a substantial threat the environment, necessitating effective remediation strategies. Phytoremediation emerges as a cost-efficient and eco-friendly approach for reducing Cd levels in the soil. In this study, the suitability of A. venetum for ameliorating Cd-contaminated soils was evaluated. Mild Cd stress promoted seedling and root growth, with the root being identified as the primary tissue for Cd accumulation. The Cd content of roots ranged from 0.35 to 0.55 mg/g under treatment with 10–50 µM CdCl2·2.5 H2O, and the bioaccumulation factor ranged from 28.78 to 84.43. Transcriptome sequencing revealed 20,292 unigenes, and 7507 nonredundant differentially expressed genes (DEGs) were identified across five comparison groups. DEGs belonging to the “MAPK signaling pathway-plant,” “monoterpenoid biosynthesis,” and “flavonoid biosynthesis pathway” exhibited higher expression levels in roots compared to stems and leaves. In addition, cytokinin-related DEGs, ROS scavenger genes, such as P450, glutathione-S-transferase (GST), and superoxide dismutase (SOD), and the cell wall biosynthesis-related genes, CSLG and D-GRL, were also upregulated in the root tissue, suggesting that Cd promotes root development. Conversely, certain ABC transporter genes, (e.g, NRAMP5), and some vacuolar iron transporters, predominantly expressed in the roots, displayed a strong correlation with Cd content, revealing the mechanism underlying the compartmentalized storage of Cd in the roots. KEGG enrichment analysis of DEGs showed that the pathways associated with the biosynthesis of flavonoids, lignin, and some terpenoids were significantly enriched in the roots under Cd stress, underscoring the pivotal role of these pathways in Cd detoxification. Our study suggests A. venetum as a potential Cd-contaminated phytoremediation plant and provides insights into the molecular-level mechanisms of root development promotion and accumulation mechanism in response to Cd stress.

Research progress on development and utilization of medicinal resources of Apocynum venetum L.

Research progress on development and utilization of medicinal resources of Apocynum venetum L.

Apocynum venetum leaf extract alleviated doxorubicin-induced cardiotoxicity by regulating organic acid metabolism in gut microbiota

Apocynum venetum leaf is commonly utilized for its beneficial effects in reducing blood pressure, inducing sedation, promoting diuresis, anti-aging, and cardioprotection, which also exhibit positive effects on the gut microbiota. The gut microbiota plays a role as an endocrine organ by producing bioactive metabolites that can directly or indirectly impact host physiology, specifically cardiovascular diseases. In this study, main chemical components of A. venetum leaf extract (AVLE) were identified by LC-MS, and an orally administered AVLE was employed to treat mice with doxorubicin (Dox)-induced cardiotoxicity. The results showed that AVLE contained hyperoside and oganic acids. The pharmacological findings revealed that AVLE regulated the gut microbiota, resulting in a significant increase in the levels of two organic acids, indole-3-propionic acid (IPA) and acetic acid (AA). Both IPA and AA exhibited the ability to reduce BNP, CK, and LDH levels in mice with Dox-induced cardiotoxicity. Moreover, IPA demonstrated an improvement in Dox-induced cardiac injury by inhibiting apoptosis, while AA promoted increased secretion of ghrelin through the parasympathetic nervous system, subsequently reducing cardiac fibrosis by decreasing collagen I, collagen III, and activin A. Hence, our study demonstrates that AVLE exerts a beneficial cardioprotective effect by modulating the gut microbiota, providing a potential novel target for the treatment and prevention of Dox-induced cardiotoxicity.

Synthesis of silver nanoclusters using a double-stranded DNA template and its application for captopril detection

The purpose of this study was to explore the feasibility and mechanism of synthesizing silver nanoclusters (AgNCs) using a double-stranded DNA (dsDNA) template and to use the AgNCs as probes for captopril detection. The results showed that the binding of silver ions towards DNA bases deduced the destruction of the initial dsDNA structure, and AgNCs with decent quantum yield (43.54%) were obtained. The detection using these AgNCs probes showed good performance for captopril, with a linear range of 0.1–0.8 μg·mL−1 and a detection limit of 0.045 μg·mL−1. Recovery results in real samples of Apocynum venetum leaf tea and Ginkgo biloba leaf tablet demonstrated its good applicability. This work not only extended the understanding of DNA-AgNCs but also provided a fast and cost-effective tool for captopril detection.

Isoquercitrin from Apocynum venetum L. Exerts Antiaging Effects on Yeasts via Stress Resistance Improvement and Mitophagy Induction through the Sch9/Rim15/Msn Signaling Pathway.

With the development of an aging sociality, aging-related diseases, such as Alzheimer's disease, cardiovascular disease, and diabetes, are dramatically increasing. To find small molecules from natural products that can prevent the aging of human beings and the occurrence of these diseases, we used the lifespan assay of yeast as a bioassay system to screen an antiaging substance. Isoquercitrin (IQ), an antiaging substance, was isolated from Apocynum venetum L., an herbal tea commonly consumed in Xinjiang, China. In the present study, we utilized molecular-biology technology to clarify the mechanism of action of IQ. The replicative lifespans of K6001 yeasts and the chronological lifespans of YOM36 yeasts were used to screen and confirm the antiaging effect of IQ. Furthermore, the reactive oxygen species (ROS) and malondialdehyde (MDA) assay, the survival assay of yeast under stresses, real-time polymerase chain reaction (RT-PCR) and Western blotting analyses, the replicative-lifespan assay of mutants, such as Δsod1, Δsod2, Δgpx, Δcat, Δskn7, Δuth1, Δatg32, Δatg2, and Δrim15 of K6001, autophagy flux analysis, and a lifespan assay of K6001 yeast after giving a mitophagy inhibitor and activator were performed. IQ extended the replicative lifespans of the K6001 yeasts and the chronological lifespans of the YOM36 yeasts. Furthermore, the reactive nitrogen species (RNS) showed no change during the growth phase but significantly decreased in the stationary phase after treatment with IQ. The survival rates of the yeasts under oxidative- and thermal-stress conditions improved upon IQ treatment, and thermal stress was alleviated by the increasing superoxide dismutase (Sod) activity. Additionally, IQ decreased the ROS and MDA of the yeast while increasing the activity of antioxidant enzymes. However, it could not prolong the replicative lifespans of Δsod1, Δsod2, Δgpx, Δcat, Δskn7, and Δuth1 of K6001. IQ significantly increased autophagy and mitophagy induction, the presence of free green fluorescent protein (GFP) in the cytoplasm, and ubiquitination in the mitochondria of the YOM38 yeasts at the protein level. IQ did not prolong the replicative lifespans of Δatg2 and Δatg32 of K6001. Moreover, IQ treatment led to a decrease in Sch9 at the protein level and an increase in the nuclear translocation of Rim15 and Msn2. These results indicated that the Sch9/Rim15/Msn signaling pathway, as well as antioxidative stress, anti-thermal stress, and autophagy, were involved in the antiaging effects of IQ in the yeasts.

Luobuma Leaf Spot Disease Caused by Alternaria tenuissima in China.

Luobuma (Apocynum venetum and Poacynum hendersonni) is widely cultivated for environmental conservation, medicinal purposes and the textile industry. In 2018, a severe leaf spot disease that attacked the leaves of Luobuma was observed in plants cultivated in Yuzhong County, Gansu Province, China. Symptoms of the disease appeared as white or off-white spots surrounded by brown margins on the leaves of A. venetum. The spots expanded and covered a large area of the leaf, presenting as "cankers" with progression of the disease, leading to leaf death. The initial symptoms of the disease on P. hendersonni were similar to the symptoms of A. venetum, with a larger disease spot than A. venetum, and the spot was black and thicker. The aim of this study was to identify the fungal species and evaluate the effectiveness of fungicides (hymexazol and zhongshengmycin) against the pathogen in vitro. The fungi species that caused the new disease was identified as Alternaria tenuissima based on the morphological characteristics, pathogenicity tests, and phylogenetic analysis of the internal transcribed spacer (ITS) region, glyceraldehyde 3-phosphate dehydrogenase (gpd), translation elongation factor 1-alpha (TEF) and the histone 3 (H3) gene sequences. The findings showed that hymexazol fungicide can be used to control leaf spot disease. This is the first report on Luobuma leaf spot disease caused by A. tenuissima in China.

Potential Implications of Hyperoside on Oxidative Stress-Induced Human Diseases: A Comprehensive Review.

Hyperoside is a flavonol glycoside mainly found in plants of the genera Hypericum and Crataegus, and also detected in many plant species such as Abelmoschus manihot, Ribes nigrum, Rosa rugosa, Agrostis stolonifera, Apocynum venetum and Nelumbo nucifera. This compound exhibits a multitude of biological functions including anti-inflammatory, antidepressant, antioxidative, vascular protective effects and neuroprotective effects, etc. This review summarizes the quantification, original plant, chemical structure and property, structure-activity relationship, pharmacologic effect, pharmacokinetics, toxicity and clinical application of hyperoside, which will be significant for the exploitation for new drug and full utilization of this compound.