Search

Plant essential oils contain abundant natural active compounds, mainly terpenes and phenylpropanes, with immense industrial and pharmaceutical applications. The opposite variations between sesquiterpenes and phenylpropanes are widespread, determining the application and value of essential oils. However, intricate regulatory mechanisms at the molecular level have not been uncovered. To this end, transcriptome, metabolome, high-performance gas chromatography, exogenous protocatechuic acid and ABA treatments were performed on P. sheareri leaves at different developmental stages. Results revealed that the content of essential oils in the young leaves (2.45 mg/g) was 70.14% higher than in mature ones (1.44 mg/g). Additionally, there were opposing variations in the accumulation of phenylpropanes and sesquiterpenes, which correlated with the differential expression genes (DEGs) enriched in the shikimate pathway, phenylpropanoid biosynthesis and related secondary metabolites pathways in P. sheareri leaves. Phenylpropanes and sesquiterpene profiles presented dynamic patterns that changed with leaf growth and were consistent with the pattern of key gene regulation in the corresponding paths. After the combined multi-omics analysis, structural genes (DHQS , TPS1 , CYP707A2) and possible interacting TFs with the key genes (i.e., SHR , JA2L , WRKY12 , WRKY76 , and ERF113) could be responsible for the opposite relationship between phenylpropanes and sesquiterpenes. Different concentrations treatments of protocatechuic acid and ABA indicated shikimate pathway mediated biosynthesis and metabolism of phenylpropanes and sesquiterpenes in the P. sheareri leaves, in which the downregulated DHQS and CYP707A2 , and upregulated TPS1 and SHR played the vital roles. Based on the identified differentially accumulated phenylpropanes, sesquiterpenes, and candidate hub DEGs, genetic and metabolic regulation mechanisms of secondary metabolites in the essential oils were further proposed, providing a new understanding of essential oils biosynthesis. Potential regulatory factors identified in this study will contribute to providing molecular traces for in-depth research on the relationship of phenylpropanes and sesquiterpenes biosynthesis, as well as product development for essential oils with higher value. [Display omitted] • Young leaves had more essential oils and sesquiterpenes than mature leaves. • Young leaves had fewer phenylpropanes than mature leaves. • DHQS , TPS1 , CYP707A2 , and SHR are candidate core genes. • Protocatechuic acid reduced DHQS expression level while increasing TPS1. • The shikimate pathway mediated the antagonism of phenylpropanes and sesquiterpenes. [ABSTRACT FROM AUTHOR]

Houttuynia cordata Thunb. (H. cordata) is a significant medicinal plant in China, known for its strong effects in healthcare and disease treatment. However, wild-harvested H. cordata often accumulates heavy metal contaminants, and currently, there is no environmentally safe method for its cultivation. This study aims to explore the influence of cultivation substrates on the growth, development, and medicinal components of H. cordata , and to elucidate the potential mechanisms underlying the increased biomass of H. cordata under hydroponic conditions using multi-omics techniques. Methodologically, we employed soilless cultivation to ensure medicinal safety and used multi-omics analysis to reveal the differential metabolites and genes associated with various cultivation methods. Our findings indicate that soilless cultivation effectively reduces H. cordata 's accumulation of benzene while maintaining medicinal component levels comparable to traditional soil cultivation. Hydroponically grown H. cordata exhibits significantly higher biomass compared to other methods. The integration of multi-omics analysis shows that differential metabolites and genes in hydroponically grown H. cordata are primarily enriched in nitrogen metabolism and photosynthetic pathways. Additionally, we found that increased nitric oxide content significantly enhances H. cordata 's photosynthesis and gene expression, promoting leaf and root growth. In conclusion, soilless cultivation reduces benzene metabolite levels in H. cordata while preserving its medicinal properties, and hydroponics facilitates its growth and development. This study lays a theoretical foundation for the industrial production of environmentally friendly, uncontaminated medicinal H. cordata. [Display omitted] • Houttuynia cordata Thunb thrives in soilless cultivation, with significant biomass increase. • Soilless cultivation effectively reduces benzene accumulation in H. cordata. • Multi-omics reveals hydroponic regulation mechanisms in H. cordata growth. [ABSTRACT FROM AUTHOR]

MYB transcription factor (TF) genes are crucial for modulating secondary metabolite biosynthesis in plants. Stevia is a valuable economic crop, and the steviol glycosides produced in its leaves are the most prevalent natural sweeteners. The present research offers a thorough genomic examination of Stevia's MYB TF gene superfamily. We identified 310 genes as putative MYB genes, out of which 176 R2R3-MYB genes were chosen for subsequent analysis. A comparative phylogenetic analysis classified these Stevia R2R3-MYB genes into nine subfamilies, with exon-intron structures and motif compositions strongly supporting this classification. Furthermore, due to its significant expansion, subfamily VIII was divided into 17 clades, and clade VIII-E was unique to Stevia. Synteny analysis revealed that the expansion of members in each subfamily, or each clade within subfamily VIII, was mainly facilitated by whole-genome duplication (WGD) as well as dispersed duplication events. Promoter detection identified multiple classes of cis-regulatory elements that are associated with responses to light, phytohormones, and environmental stressors. Expression analysis revealed that different subfamilies or clades of R2R3-MYB genes exhibited diverse expression profiles across multiple tissue types and at various phases of leaf growth. Meanwhile, SrMYB32 , 15 , 114/168, 163 , 125/126 , 33 , 153/154 showed significant expression differences in two Stevia varieties with different steviol glycosides content. The present research lays a firm basis for future functional analysis of R2R3-MYBs that play important roles in the biosynthesis of steviol glycosides. • A systematic analysis of Stevia R2R3-MYB genes was performed, including phylogenetic motif, and synteny analysis. • The expansion of Stevia R2R3-MYB genes was mainly facilitated by whole-genome duplication and dispersed duplication events. • Some R2R3-MYB genes were differentially expressed in Stevia cultivars with different steviol glycoside contents. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) has evolved to tolerate almost all known β-lactam antibiotics, and been exhibiting resistance to vancomycin. Developing new drugs against the MRSA infection are urgently needed. Natural resource is enriched with antimicrobial molecules. Here, we report an extract from leaves of Cyclocarya paliurus (ECPL), a species of tree native to China and being traditionally cultivated as medicinal plant, which shows a broad spectrum of bacteriostatic and bactericidal effects at MIC 50 15.99 ± 0.55 μg/ml against methicillin-susceptible and -resistant S. aureus. The ECPL suppresses bacterial expression of FtsZ at both transcriptional and protein levels, inhibits its GTPase activity, blocks the assembly dynamics of FtsZ, and disrupts the formation of Z-ring. The bacteria cells fail to divide, enlarge initially, and lyse eventually. In mouse model, the ECPL facilitates skin wound healing with MRSA infection as effective as vancomycin. Our study unveils the potential of identifying novel molecule in ECPL for development of new class of antibiotic against both methicillin-susceptible and -resistant S. aureus , and support domestication of the C. paliurus growing from wild to cultivated, and further scale up the cultivation into industrialized farm for sustainable harvest for pharmaceutic interest. [Display omitted] • An extract from Cyclocarya paliurus (ECPL) leaves shows anti-MRSA activity. • The ECPL suppresses bacterial FtsZ at transcriptional and protein levels and eliminates the GTPase enzyme activity. • Bacteria abort Z-ring formation , fail to divide, and die. • This effect bypasses known resistance machineries and shows a potential for new antibiotic development. • Domesticating and scaling up the cultivation will guaranty sustainable harvest for the pharmaceutic interest. [ABSTRACT FROM AUTHOR]

Revealing the dynamic accumulation and synthesizing mechanism of medicinal bioactive products is critical for the evaluation and utilization of crops in medicinal industry. Huangqin (Scutellaria baicalensis Georgi) and Nianmao-Huangqin (Scutellaria viscidula Bge) are important medicinal crops containing flavonoids with good bioactivities. Previous studies have found significant differences of flavonoid contents between the two species. Nevertheless, the dynamic changes of bioactive products and related differential synthesizing mechanism remains unknown. In this study, an inter-specific comparative study was reported on the dynamic accumulation of eight bioactive products (scutellarin, scutellarein, baicalin, wogonoside, apigenin, baicalein, wogonin, and chrysin) and the expression of seven key enzyme genes in different organs (root, stem, and leaf) during different growth stages (May, June, July, August, September, and October) of S. baicalensis and S. viscidula. The results showed that the eight bioactive products were differentially accumulated in different growth stages for the two species. Specifically, the contents of five ingredients (except wogonoside, scutellarein and apigenin) in roots of S. baicalensis were significantly higher than those in S. viscidula in harvest stage (October). Meanwhile, the relative expression of seven key enzyme genes in baicalin synthesizing pathway showed significant spatio-temporal specificities. The expression of UBGAT in downstream baicalin synthesis was significantly higher in roots of S. baicalensis than that of S. viscidula (P < 0.05). Moreover, there exist significant correlations between the content of bioactive products and the expression of key enzyme genes. The expression of upstream (CLL-7 , FNSII-1 , FNSII-2) and downstream (F6H and UBGAT) key enzyme genes were significantly positively correlated with the contents of baicalin in both S. baicalensis and S. viscidula. On the contrary, the expression of GUS was significantly negatively correlated with the content of baicalin in the two species. Collectively, these results give clear evidences that the expression of key enzyme genes (e.g., FNSII-2 , GUS , and UBGAT) in baicalin synthesis is probably the main reason for the difference of bioactive products, suggesting that S. viscidula can be used as an alternative to S. baicalensis in pharmaceutical industry. Furthermore, these findings will provide a theoretical basis for exploring the inter-specific differences of bioactive products in medicinal crops within the same genus, thereby revealing the molecular mechanism of quality formation of Chinese medicinal materials. • Eight bioactive products showed content difference between two Scutellaria crops. • Seven key genes were differentially expressed in S. baicalensis and S. viscidula. • Difference of product content was correlated with difference of gene expression. • S. viscidula can be used as alternative medicinal source to S. baicalensis. • Molecular mechanism of differential bioactive product contents was revealed. [ABSTRACT FROM AUTHOR]

Highlights: [•] The relative salt tolerance of six cultivars of Ricinus communis L. was compared in two separate experiments. [•] Seedling emergence was inhibited by salinity at 17.5dSm−1 in all cultivars except for ‘Memphis’. [•] Salinity at 1.9 and 10.5dSm−1 enhanced seedling emergence in some cultivars. [•] ‘Memphis’ was more tolerant to salinity stress among the six cultivars tested. [ABSTRACT FROM AUTHOR]

Abstract: Tobacco being a non-food commercial crop, has gained attention for alternate uses apart from its use for making cigarettes. Leaf yield is a major economic produce in tobacco. In order to screen for mutants that enhance leaf yield and its associated metabolic traits, we generated an Ethyl Methane Sulphonate (EMS) mutant population also referred to as TILLING (Targeting Induced Local Lesions IN Genomes) population. DNA and seed libraries were prepared from 7800M2 plants. High throughput sequencing technology combined with 3D pooling of amplicons from 3072M2 plants was deployed for mutation screening. In total, seven induced mutations were identified in genes potentially linked with leaf biomass (Ntfw2.2 and NtLs) and secondary metabolism (NtMYB12 and NtGGR). Overall mutation density of one mutation per 1.423 million bases or ∼3162 mutations per genome was observed in the population. Out of the three candidate point mutations identified in Ntfw2.2, the mutation that resulted a premature stop codon was converted to a simple High Resolution Melting (HRM) DNA marker. Additionally, mutants with traits such as increase in number of leaves and broader leaves were selected from the population and advanced to further generations. This study provided evidence to suggest that mutants with agronomic superior phenotypes identified by forward and reverse genetic approaches (TILLING) could contribute potentially towards crop improvement in tobacco. [Copyright &y& Elsevier]

Abstract: This study is carried out in order to evaluate the fatty acids content and composition, the phenolic content and the antioxidant activity of Salvia sclarea rosette leaves under saline conditions. The total fatty acid content decreased significantly with salt concentrations. Concerning the composition, the treatment of 25mM NaCl decreased the palmitic, stearic and arachidic acids proportions while it increased the unsaturated form of these fatty acids in contrast to the two other treatments (50 and 75mM). The phenolic contents were higher at 25 and 50mM than that at control, but decreased significantly with the application of 75mM. Antioxidant activity of the methanol extracts was determined by DPPH and β-carotene/linoleic acid assays. In these test systems, the highest activity was exhibited at 25 and 50mM NaCl and was reduced significantly with increasing NaCl levels. Hence, S. sclarea under these two moderate salt concentrations should be used commercially in foodstuffs like sage and rosemary. [Copyright &y& Elsevier]

• Phenotypic plasticity exhibited in ginkgo growth and metabolite traits. • Low temperature is considered to be the key factor restricting ginkgo growth. • High quality areas of ginkgo cultivation would shift northward and upward. Ginkgo (Ginkgo biloba L.) is an ancient medicinal tree species that is widely cultivated in China for its leaves which possess pharmacologically active metabolites. Knowledge about the effects of climate change on ginkgo leaf yield (biomass) and quality (target metabolites concentration) remains unknown. Here, we first examined the extent of several phenotypic traits (growth: leaf area and weight, main branch basal diameter and length; metabolites: concentration of flavonoids, ginkgolides, and polyprenols) variation of genetically homogeneous ginkgo clones (including gender differences) along climatic gradients. Second, we used univariate and bivariate modeling techniques to quantify the impact of several essential climatic factors on the performance of the studied phenotypic traits. Finally, we predicted the growth potential of the studied traits and delineated their suitable production areas under current and future climate conditions. Results showed that the studied 4 growth and 12 metabolites traits varied significantly (P < 0.05) among the 17 assessed diverse growing environments, while female trees consistently outperformed male trees for growth traits, but not for metabolites. Climate variables related to sub-zero temperature were considered to be the most key factor restricting the distribution of ginkgo (growth potential); however, they promoted the biosynthesis of some defense compounds (e.g., flavonoids). Future projections under the RCP8.5 scenario indicated that the area suitable for ginkgo growth (leaf area) would increase by mid-century as well the high-yield, high-quality areas of ginkgo cultivation would shift northward and upward. [ABSTRACT FROM AUTHOR]

• The rapid growth period of the sympodial leaves was moved forward in the modern cultivars. • The succession of the cultivars caused an extension of rapid growth period of boll. • Photosynthates competition between sympodial leaf and boll is alleviated in a boll–leaf system of the modern cultivars. The yield of cotton (Gossypium hirsutum L.) has increased steadily with the release of different cultivars over the years in Xinjiang, China. However, the reasons for this increased yield have been controversial. As the sympodial leaf and boll within the boll–leaf system of cotton develop together, their competition for photosynthates is intense during their growth, which may be an important factor influencing boll weight. Consequently, we speculated that shortening period during which the sympodial leaf and boll develop together, which would alleviate photosynthates competition, might contribute to boll growth during the succession of cotton cultivars. To test this hypothesis, changes in yield characteristics and photosynthetic performance were studied by examining the main cotton cultivars from four breeding eras (1980s, 1990s, 2000s, and 2010s) in the Xinjiang early-maturing cotton region. The results showed that the single boll weight and the number of bolls increased gradually, and the yield increased steadily with cultivar succession. In the boll–leaf system of cotton, the rapid growth period of the sympodial leaves moved forward, thus reducing the time during which the sympodial leaves and bolls developed simultaneously; at the same time, the rapid growth duration of boll was extended during cultivar succession. In addition, the succession of cotton cultivars was accompanied by increased leaf area, increased leaf photosynthetic rate (Pn) after flowering, and an extension of photosynthetic functional duration within the boll–leaf system. Compared with the sympodial leaves, the photosynthetic performance of the main-stem leaves was improved more obviously in the same boll–leaf system. Therefore, during cotton cultivar succession in Xinjiang, the photosynthates competition between sympodial leaf growth and boll development was significantly alleviated within a boll–leaf system with the improvement of photosynthetic performance, which may further extend the rapid growth duration of boll, thus enhancing single boll weight and yield of cotton. [ABSTRACT FROM AUTHOR]

• Bud growth fertilization increased ginkgo leaf number in spring. • Bud growth fertilization with high N but low P and K had more notable effect on leaf number. • Topdressing leaf growth fertilization in summer promoted flavonoid accumulation. • Combined application of bud and leaf growth fertilization improved ginkgo leaf flavonoid yield. Higher flavonoids yield can increase economic and industrial efficiency of Ginkgo biloba Linn. leaf-harvesting plantation. However, high-temperature limits ginkgo leaf flavonoids production in warm climates regions. Few studies have reported on methods that may improve ginkgo leaf flavonoids yield by increasing leaf productivity and flavonoids content simultaneously. This study investigated the effects of combined application of fertilizer for bud growth (FBG) and fertilizer for leaf growth (FLG) on the growth, productivity and flavonoids accumulation of ginkgo leaves, aiming to optimize fertilization schemes for improving leaf flavonoids yield of ginkgo in high-temperature regions. Results revealed that FBG significantly improved twig bud break, twig number, and twig elongation, and increased leaf number (up to 446±27.38 per four-year-old seedling) in spring. Topdressing FLG in summer moderated the decline of leaf SPAD (soil and plant analyzer development) values, modulated leaf nutrient content, and significantly increased single leaf dry weight, antioxidative enzyme activities, and leaf flavonoids content. Dry leaf productivity, flavonoids content, and flavonoids yield of four-year-old ginkgo with combined application of FBG and FLG was 103±16.05 g/plant, 6.54±0.13 mg/g, and 615.71±58.22 mg/plant, respectively, which were comparably high in reference to those in the central production region. These results suggest that the integrated application of FBG and FLG is an effective approach for improving ginkgo leaf flavonoids yield in high-temperature regions. [ABSTRACT FROM AUTHOR]

• The metabolic profiling in Vaccinium bracteatum Thunb. leaves were examined. • Dynamic changes of metabolites between different leaf samples were revealed. • Several discriminatory secondary metabolites accounted for the blue pigments. • Several discriminatory free amino acids contributed to the formation of pigment. • A hypothesis of the seasonal differences of blue pigments was presented. Vaccinium bracteatum Thunb. leaf is a valuable source of natural pigment to dye food, hair, and clothing for a thousand of years in China. However, the seasonal differences of blue hue of pigments have not been fully demonstrated. In this research, V. bracteatum Thunb. leaves were collected from eight months for metabolite analysis. The global metabolic profile in leaves was examined to distinguish the differential metabolites and monitor the dynamic changes. This research revealed that several discriminatory secondary metabolites were monotropein derivatives, flavonoid glycosides and chlorogenic acid isomers by LCMS-untargeted approach. The changes of monotropein derivatives and dimers occurred in a season-dependent manner which almost showed higher abundances in spring. Meanwhile, several free amino acids changed dramatically by HPLC-targeted measurement. Particularly, Ala, Glu, and Asp caused a positive impact on blue color. Ser, Arg, and His were negatively correlated with the color. This research provided the first evidence that the seasonal differences of blue pigment are ascribed to the systemic changes of monotropein derivatives and free amino acids in V. bracteatum Thunb. leaves. [ABSTRACT FROM AUTHOR]