In order to compare the differences in growth and secondary metabolite accumulation of Panax quinquefolius between understory and field planting, growth indexes, photosynthetic characteristics, soil enzyme activities, secondary metabolite contents, and antioxidant activities of P. quinquefolius under different planting modes were examined and compared, and One-way analysis of variance(ANOVA) and correlation analyses were carried out by using the software SPSS 25.0 and GraphPad Prism 9.5. The Origin 2021 software was used for plotting. The results showed that compared with those under field planting, the plant height, leaf length, leaf width, photosynthetic rate, and chlorophyll content of P. quinquefolius under understory planting were significantly reduced, and arbuscular mycorrhizal fungi(AMF) infestation rate and infestation intensity, ginsenoside content, and antioxidant activity were significantly increased. The activities of inter-root soil urease, sucrase, and catalase increased, while the activities of non-inter-root soil urease and alkaline phosphatase increased. Correlation analyses showed that the plant height and leaf length of P. quinquefolius plant were significantly positively correlated with net photosynthetic rate, transpiration rate, chlorophyll content, and electron transfer rate(P<0.05), while ginsenoside content was significantly negatively correlated with net photosynthetic rate, chlorophyll content, and electron transfer rate(P<0.05) and significantly positively correlated with AMF infestation rate and infestation intensity(P<0.05). In addition, ginsenoside content was significantly positively correlated with the activities of inter-root soil sucrase, urease, and catalase(P<0.05). This study provides basic data for revealing the mechanism of secondary metabolite accumulation in P. quinquefolius under understory planting and for exploring and practicing the ecological mode of P. quinquefolius under understory planting.
Panax/microbiology* ; China ; Secondary Metabolism ; Soil/chemistry* ; Photosynthesis ; Plant Leaves/metabolism* ; Chlorophyll/metabolism* ; Mycorrhizae

To study the differences in transcript levels among different organs of Spatholobus suberectus and to explore the genes encoding enzymes related to the catechin biosynthesis pathway, this study utilized the genome and full-length transcriptome data of S. suberectus as references. Transcriptome sequencing and bioinformatics analysis were performed on five different organs of S. suberectus-roots, stems, leaves, flowers, and fruits-using the Illumina NovaSeq 6000 platform. A total of 115.28 Gb of clean data were obtained, with GC content values ranging from 45.19% to 47.54%, Q20 bases at 94.17% and above, and an overall comparison rate with the reference genome around 90%. In comparisons between the stem and root, stem and leaf, stem and flower, and stem and fruit, 10 666, 9 674, 9 320, and 5 896 differentially expressed genes(DEGs) were identified, respectively. The lowest number of DEGs was found in the stem and root comparison group. KEGG enrichment analysis revealed that the DEGs were mainly concentrated in the pathways of phytohormone signaling, phenylalanine biosynthesis, etc. A total of 39 genes were annotated in the catechin biosynthesis pathway, with at least one highly expressed gene found in all organs. Among these, PAL1, PAL2, C4H1, C4H3, 4CL1, 4CL2, and DFR2 showed high expression in the stems, suggesting that they may play important roles in the biosynthesis of flavonoids in S. suberectus. This study aims to provide important information for the in-depth exploration of the regulation of catechin biosynthesis in S. suberectus through transcriptome analysis of its different organs and to provide a reference for the further realization of S. suberectus varietal improvement and molecular breeding.
Catechin/biosynthesis* ; Gene Expression Profiling ; Gene Expression Regulation, Plant ; Plant Proteins/metabolism* ; Fabaceae/metabolism* ; Transcriptome ; Flowers/metabolism* ; Plant Stems/metabolism* ; Plant Leaves/metabolism* ; Plant Roots/metabolism* ; Fruit/metabolism*

The anti-inflammatory phytochemical investigation of the leaves of Illicium dunnianum (I. dunnianum) resulted in the isolation of five pairs of new lignans (1-5), and 7 known analogs (6-12). The separation of enantiomer mixtures 1-5 to 1a/1b-5a/5b was achieved using a chiral column with acetonitrile-water mixtures as eluents. The planar structures of 1-2 were previously undescribed, and the chiral separation and absolute configurations of 3-5 were reported for the first time. Their structures were determined through comprehensive spectroscopic data analysis [nuclear magnetic resonance (NMR), high-resolution electrospray ionization mass (HR-ESI-MS), infrared (IR), and ultraviolet (UV)] and quantum chemistry calculations (ECD). The new isolates were evaluated by measuring their inhibitory effect on NO in lipopolysaccharide (LPS)-stimulated BV-2 cells. Compounds 1a, 3a, 3b, and 5a demonstrated partial inhibition of NO production in a concentration-dependent manner. Western blot and real-time polymerase chain reaction (PCR) assays revealed that 1a down-regulated the messenger ribonucleic acid (mRNA) levels of tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), COX-2, and iNOS and the protein expressions of COX-2 and iNOS. This research provides guidance and evidence for the further development and utilization of I. dunnianum.
Lignans/isolation & purification* ; Plant Leaves/chemistry* ; Anti-Inflammatory Agents/isolation & purification* ; Mice ; Animals ; Molecular Structure ; Plant Extracts/pharmacology* ; Illicium/chemistry* ; Cyclooxygenase 2/immunology* ; Interleukin-6/immunology* ; Nitric Oxide/metabolism* ; Cell Line ; Tumor Necrosis Factor-alpha/immunology* ; Nitric Oxide Synthase Type II/immunology* ; Lipopolysaccharides

Microalgae possess high photosynthetic efficiency, robust adaptability, and substantial biomass, serving as excellent biological resources for large-scale cultivation. Malic enzyme (ME), a ubiquitous metabolic enzyme in living organisms, catalyzes the decarboxylation of malate to produce pyruvate, CO₂, and NAD(P)H, playing a role in multiple metabolic pathways including energy metabolism, photosynthesis, respiration, and biosynthesis. In this study, we identified the Scenedesmus quadricauda malic enzyme gene (SqME) and its biological functions, aiming to provide excellent target genes for the genetic improvement of higher plants. Based on the RNA-seq data from S. quadricauda under the biofilm cultivation mode with high CO₂ and light energy transfer efficiency and small water use, a highly expressed gene (SqME) functionally annotated as ME was cloned. The physicochemical properties of the SqME-encoded protein were systematically analyzed by bioinformatics tools. The subcellular localization of SqME was determined via transient transformation in Nicotiana benthamiana leaves. The biological functions of SqME were identified via genetic transformation in Nicotiana tabacum, and the potential of SqME in the genetic improvement of higher plants was evaluated. The ORF of SqME was 1 770 bp, encoding 590 amino acid residues, and the encoded protein was located in chloroplasts. SqME was a NADP-ME, with the typical structural characteristics of ME. The ME activity in the transgenic N. tabacum plant was 1.8 folds of that in the wild-type control. Heterologous expression of SqME increased the content of chlorophyll a, chlorophyll b, and total chlorophyll by 20.9%, 26.9%, and 25.2%, respectively, compared with the control. The transgenic tobacco leaves showed an increase of 54.0% in the fluorescence parameter NPQ and a decrease of 30.1% in Fo compared with the control. Moreover, the biomass, total lipids, and soluble sugars in the transgenic tobacco leaves enhanced by 20.5%, 25.7%, and 9.5%, respectively. On the contrary, the starch and protein content in the transgenic tobacco leaves decreased by 22.4% and 12.2%, respectively. Collectively, the SqME-encoded protein exhibited a strong enzymatic activity. Heterologous expressing of SqME could significantly enhance photosynthetic protection, photosynthesis, and biomass accumulation in the host. Additionally, SqME can facilitate carbon metabolism remodeling in the host, driving more carbon flux towards lipid synthesis. Therefore, SqME can be applied in the genetic improvement of higher plants for enhancing photosynthetic carbon fixation and lipid accumulation. These findings provide scientific references for mining of functional genes from S. quadricauda and application of these genes in the genetic engineering of higher plants.
Nicotiana/genetics* ; Photosynthesis/physiology* ; Malate Dehydrogenase/biosynthesis* ; Plant Leaves/genetics* ; Scenedesmus/enzymology* ; Carbon Cycle/genetics* ; Lipid Metabolism/genetics* ; Plants, Genetically Modified/metabolism*

Rice (Oryza sativa L.) is an important food crop. The appearance of lesion mimics in rice leads to phytohormone disorders, which affects rice adaptation to environmental stresses and ultimately reduces the yield and quality. To explore whether the changes in the adaptability of rice lesion-mimic mutants to stressful environments are caused by the disorder of phytohormone metabolism in plants. In this study, we screened an ethyl methane sulfonate-treated population of the japonica cultivar 'Taipei 309' for a mutant with rust-like spots on leaves at the early tillering stage and brown-red spots at maturity and named it rsl1 (rust spotted leaf 1). Compared with the wild type, rsl1 showed decreases in plant height, panicle length, primary branch number, secondary branch number, filled grains per panicle, seed-setting rate, and 1 000-grain weight, and an increase in number of effective panicles. Genetic analysis indicated that rsl1 was controlled by a single recessive nuclear gene. RSL1 was localized between two molecular markers, B7-7 and B7-9, on rice chromosome 7 by map-based cloning. PCR sequencing of the annotated genes in this interval revealed a mutation of C1683A on the eighth exon of SPL5 (LOC_Os07g10390) in rsl1, which resulted in premature termination of protein translation. Exogenous phytohormone treatments showed that rsl1 was less sensitive to salicylic acid (SA), abscisic acid (ABA), and indo-3-acetic acid (IAA) and more sensitive to methyl jasmonate (MeJA) and gibberellin acid (GA) than the wild type. In addition, the survival rate of rsl1 was lower than that of the wild type under salt, alkali, drought, and high temperature stresses, and it was higher than that of the wild type under cold stress. Quantitative real-time polymerase chain reaction (qRT-PCR) results showed that RSL1 was involved in the regulation of ABA, SA, MeJA, IAA, and GA-related genes under abiotic stresses. The present study showed that the RSL1 mutation led to the appearance of lesion mimics and affected the growth, development, and stress resistance of rsl1 under abiotic stresses. The study of the functional mechanism of this gene can provide theoretical guidance for the research on rice stress resistance.
Oryza/microbiology* ; Stress, Physiological/genetics* ; Plant Diseases/genetics* ; Cloning, Molecular ; Chromosome Mapping ; Plant Growth Regulators/metabolism* ; Plant Proteins/genetics* ; Mutation ; Cyclopentanes ; Genes, Plant ; Plant Leaves/genetics* ; Oxylipins

This study explored the growth-promoting effect and mechanism of the endophytic bacterium Kocuria rosea on Rehmannia glutinosa, aiming to provide a scientific basis for the development of green bacterial fertilizer. R. glutinosa 'Jinjiu' was treated with K. rosea, and the shoot parameters including leaf length, leaf width, plant width, and stem diameter were measured every 15 days. After 120 days, the shoots and roots were harvested. The root indicators(root number, root length, root diameter, root fresh weight, root dry weight, root volume, and root vitality) and secondary metabolites(catalpol, rehmannioside A, rehmannioside D, verbascoside, and leonuride) were determined. The R. glutinosa growth-promoting mechanism of K. rosea was discussed from the effect of K. rosea on the nutrient element content in R. glutinosa and rhizosphere soil and the genome information of this plant. After application of K. rosea, the maximum increases in leaf length, leaf width, plant width, and stem diameter were 35.67%(60 d), 25.39%(45 d), 40.17%(60 d), and 113.85%(45 d), respectively. The root number, root length, root diameter, root volume, root fresh weight, root dry weight, and root viability increased by 41.71%, 45.10%, 48.61%, 94.34%, 101.55%, 147.61%, and 42.08%, respectively. In addition, the content of rehmannioside A and verbascoside in the root of R. glutinosa increased by 76.67% and 69.54%, respectively. K. rosea promoted the transformation of nitrogen(N), phosphorus(P), and potassium(K) in the rhizosphere soil into the available state. Compared with that in the control, the content of available N(54.60 mg·kg~(-1)), available P(1.83 μmol·g~(-1)), and available K(83.75 mg·kg~(-1)) in the treatment with K. rosea increased by 138.78%, 44.89%, and 14.34%, respectively. The content of N, P, and K in the treatment group increased by 293.22%, 202.63%, and 23.80% in the roots and by 23.60%, 107.23%, and 134.53% in the leaves of R. glutinosa, respectively. K. rosea carried the genes related to colonization(rbsB, efp, bcsA, and gmhC), N, P, and K metabolism(narG, narH, narI, nasA, nasB, GDH2, pyk, aceB, ackA, CS, ppa, ppk, ppk2, pstS, pstA, pstB, and pstC), and indole-3-acetic acid and zeatin synthesis(iaaH and miaA). Further studies showed that K. rosea could colonize the roots of R. glutinosa and secrete indole-3-acetic acid(3.85 μg·mL~(-1)) and zeatin(0.10 μg·mL~(-1)). In summary, K. rosea promotes the growth of R.ehmannia glutinosa by enhancing the nutrient uptake, which provides a theoretical basis for the development of plant growth-promoting microbial products.
Rehmannia/metabolism* ; Endophytes/metabolism* ; Plant Roots/growth & development* ; Micrococcaceae/genetics* ; Data Mining ; Plant Leaves/metabolism* ; Genomics ; Rhizosphere

GI (GIGANTEA) is one of the output key genes for circadian clock in the plant. The JrGI gene was cloned and its expression in different tissues was analyzed to facilitate the functional research of JrGI. RT-PCR (reverse transcription-polymerase chain reaction) was used to clone JrGI gene in present study. This gene was then analyzed by bioinformatics, subcellular localization and gene expression. The coding sequence (CDS) full length of JrGI gene was 3 516 bp, encoding 1 171 amino acids with a molecular mass of 128.60 kDa and a theoretical isoelectric point of 6.13. It was a hydrophilic protein. Phylogenetic analysis showed that JrGI of 'Xinxin 2' was highly homologous to GI of Populus euphratica. The result of subcellular localization showed that JrGI protein was located in nucleus. The JrGI, JrCO and JrFT genes in female flower buds undifferentiated and early differentiated of 'Xinxin 2' were analyzed by RT-qPCR (real-time quantitative PCR). The results showed that the expression of JrGI, JrCO and JrFT genes were the highest on morphological differentiation, implying the temporal and special regulation of JrGI in the differential process of female flower buds of'Xinxin 2'. In addition, RT-qPCR analysis showed that JrGI gene was expressed in all tissues examined, whereas the expression level in leaves was the highest. It is suggested that JrGI gene plays a key role in the development of walnut leaves.
Juglans/genetics* ; Phylogeny ; Plant Leaves ; Cloning, Molecular ; Gene Expression Regulation, Plant ; Plant Proteins/metabolism*

Phytoremediation plays an important role in the treatment of heavy metal pollution in soil. In order to elucidate the mechanism of salicylic acid (SA) on copper absorption, seedlings from Xuzhou (with strong Cu-tolerance) and Weifang Helianthus tuberosus cultivars (with weak Cu-tolerance) were selected for pot culture experiments. 1 mmol/L SA was sprayed upon 300 mg/kg soil copper stress, and the photosynthesis, leaf antioxidant system, several essential mineral nutrients and the changes of root upon copper stress were analyzed to explore the mechanism of copper resistance. The results showed that Pn, Tr, Gs and Ci upon copper stress decreased significantly compared to the control group. Meanwhile, chlorophyll a, chlorophyll b and carotenoid decreased with significant increase in initial fluorescence (F₀), maximum photochemical quantum yield of PSⅡ (Fv/Fm), electron transfer rate (ETR) and photochemical quenching coefficient (qP) content all decreased. The ascorbic acid (AsA) content was decreased, the glutathione (GSH) value was increased, the superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activity in the leaves were decreased, and the peroxidase (POD) activity was significantly increased. SA increased the Cu content in the ground and root system, and weakened the nutrient uptake capacity of K, Ca, Mg, and Zn in the root stem and leaves. Spray of exogenous SA can maintain the opening of leaf stomata, improve the adverse effect of copper on photosynthetic pigment and PSⅡ reaction center. Mediating the SOD and APX activity started the AsA-GSH cycle process, effectively regulated the antioxidant enzyme system in chrysanthemum taro, significantly reduced the copper content of all parts of the plant, and improved the ion exchange capacity in the body. External SA increased the content of the negative electric group on the root by changing the proportion of components in the root, promoted the absorption of mineral nutrient elements and the accumulation of osmoregulatory substances, strengthened the fixation effect of the root on metal copper, and avoided its massive accumulation in the H. tuberosus body, so as to alleviate the inhibitory effect of copper on plant growth. The study revealed the physiological regulation of SA upon copper stress, and provided a theoretical basis for planting H. tuberosus to repair soil copper pollution.
Antioxidants ; Copper ; Helianthus/metabolism* ; Salicylic Acid/pharmacology* ; Chlorophyll A/pharmacology* ; Spectroscopy, Fourier Transform Infrared ; Chlorophyll/pharmacology* ; Ascorbic Acid ; Superoxide Dismutase/metabolism* ; Photosynthesis ; Glutathione ; Plant Leaves ; Stress, Physiological ; Seedlings

This paper aimed to investigate the effect of total flavonoids of buckwheat flower and leaf on myocardial cell apoptosis and Wnt/β-catenin/peroxisome proliferator-activated receptor γ(PPARγ) pathway in arrhythmic rats. SD rats were randomly divided into a control group, a model group, a low-dose(20 mg·kg~(-1)) group of total flavonoids of buckwheat flower and leaf, a medium-dose(40 mg·kg~(-1)) group of total flavonoids of buckwheat flower and leaf, a high-dose(80 mg·kg~(-1)) group of total flavonoids of buckwheat flower and leaf, a propranolol hydrochloride(2 mg·kg~(-1)) group, with 12 rats in each group. Except the control group, rats in other groups were prepared as models of arrhythmia by sublingual injection of 1 mL·kg~(-1) of 0.002% aconitine. After grouping and intervention with drugs, the arrhythmia, myocardial cells apoptosis, myocardial tissue glutathione peroxidase(GSH-Px), catalase(CAT), malondialdehyde(MDA), serum interleukin-6(IL-6), prostaglandin E2(PGE2) levels, myocardial tissue apoptosis, and Wnt/β-catenin/PPARγ pathway-related protein expression of rats in each group were measured. As compared with the control group, the arrhythmia score, the number of ventricular premature beats, ventricular fibrillation duration, myocardial cell apoptosis rate, MDA levels in myocardial tissues, serum IL-6 and PGE2 levels, Bax in myocardial tissues, and Wnt1 and β-catenin protein expression levels increased significantly in the model group, whereas the GSH-Px and CAT levels, and Bcl-2 and PPARγ protein expression levels in myocardial tissues reduced significantly. As compared with the model group, the arrhythmia score, the number of ventricular premature beats, ventricular fibrillation duration, myocardial cell apoptosis rate, MDA leve in myocardial tissues, serum IL-6 and PGE2 levels, Bax in myocardial tissues, and Wnt1 and β-catenin protein expression levels reduced in the drug intervention groups, whereas the GSH-Px and CAT levels and Bcl-2 and PPARγ protein expression levels in myocardial tissues increased. The groups of total flavonoids of buckwheat flower and leaf were in a dose-dependent manner. There was no significant difference in the levels of each index in rats between the propranolol hydrochloride group and the high-dose group of total flavonoids of buckwheat flower and leaf. The total flavonoids of buckwheat flower and leaf inhibit the activation of Wnt/β-catenin pathway, up-regulate the expression of PPARγ, reduce oxidative stress and inflammatory damage in myocardial tissues of arrhythmic rats, reduce myocardial cell apoptosis, and improve the symptoms of arrhythmia in rats.
Rats ; Animals ; PPAR gamma/metabolism* ; Fagopyrum/genetics* ; Rats, Sprague-Dawley ; bcl-2-Associated X Protein ; beta Catenin/metabolism* ; Interleukin-6 ; Flavonoids/pharmacology* ; Propranolol/pharmacology* ; Ventricular Fibrillation ; Dinoprostone ; Wnt Signaling Pathway ; Plant Leaves/metabolism* ; Flowers/metabolism* ; Apoptosis ; Cardiac Complexes, Premature

This study aimed to investigate the biological effects and underlying mechanisms of the total ginsenosides from Panax ginseng stems and leaves on lipopolysaccharide(LPS)-induced acute lung injury(ALI) in mice. Sixty male C57BL/6J mice were randomly divided into a control group, a model group, the total ginsenosides from P. ginseng stems and leaves normal administration group(61.65 mg·kg~(-1)), and low-, medium-, and high-dose total ginsenosides from P. ginseng stems and leaves groups(15.412 5, 30.825, and 61.65 mg·kg~(-1)). Mice were administered for seven continuous days before modeling. Twenty-four hours after modeling, mice were sacrificed to obtain lung tissues and calculate lung wet/dry ratio. The number of inflammatory cells in bronchoalveolar lavage fluid(BALF) was detected. The levels of interleukin-1β(IL-1β), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α) in BALF were detected. The mRNA expression levels of IL-1β, IL-6, and TNF-α, and the levels of myeloperoxidase(MPO), glutathione peroxidase(GSH-Px), superoxide dismutase(SOD), and malondialdehyde(MDA) in lung tissues were determined. Hematoxylin-eosin(HE) staining was used to observe the pathological changes in lung tissues. The gut microbiota was detected by 16S rRNA sequencing, and gas chromatography-mass spectrometry(GC-MS) was applied to detect the content of short-chain fatty acids(SCFAs) in se-rum. The results showed that the total ginsenosides from P. ginseng stems and leaves could reduce lung index, lung wet/dry ratio, and lung damage in LPS-induced ALI mice, decrease the number of inflammatory cells and levels of inflammatory factors in BALF, inhibit the mRNA expression levels of inflammatory factors and levels of MPO and MDA in lung tissues, and potentiate the activity of GSH-Px and SOD in lung tissues. Furthermore, they could also reverse the gut microbiota disorder, restore the diversity of gut microbiota, increase the relative abundance of Lachnospiraceae and Muribaculaceae, decrease the relative abundance of Prevotellaceae, and enhance the content of SCFAs(acetic acid, propionic acid, and butyric acid) in serum. This study suggested that the total ginsenosides from P. ginseng stems and leaves could improve lung edema, inflammatory response, and oxidative stress in ALI mice by regulating gut microbiota and SCFAs metabolism.
Mice ; Male ; Animals ; Ginsenosides/pharmacology* ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-6 ; Panax/genetics* ; Lipopolysaccharides/adverse effects* ; Gastrointestinal Microbiome ; RNA, Ribosomal, 16S ; Mice, Inbred C57BL ; Acute Lung Injury/genetics* ; Lung/metabolism* ; Superoxide Dismutase/metabolism* ; Plant Leaves/metabolism* ; RNA, Messenger