Different extraction methods shape the phenolic signature and biological activity of Morinda lucida extracts: A novel source of bioactive compounds preparing functional applications.

The extraction of bioactive compounds is based on the application of various extraction techniques. Therefore, the stem and root bark of the plant species Morinda lucida L. were used in this research, while the extraction procedure was performed using three extraction techniques: HAE (homogenizer extraction), UAE (ultrasound extraction) as modern, and MAC (maceration) as conventional extraction technique. The presence of different classes of secondary metabolites was determined using the UHPLC method, while the content of total phenols and flavonoids was determined spectrophotometrically. The biological potential was investigated by in vitro antioxidant and enzyme assays. Different extraction technologies showed significant differences in only two classes of phenols, namely lignans and phenolic acids, which were significantly higher in HAE than in UAE and MAC. These findings highlight the significant effect of stem and bark extracts of M. lucida, opening the way for innovative industrial exploitation of these matrices.

Weight-induced radial growth in plant stems depends on PIN3.

How multiple growth programs coordinate during development is a fundamental question in biology. During plant stem development, radial growth is continuously adjusted in response to longitudinal-growth-derived weight increase to guarantee stability.1,2,3 Here, we demonstrate that weight-stimulated stem radial growth depends on the auxin efflux carrier PIN3, which, upon weight increase, expands its cellular localization from the lower to the lateral sides of xylem parenchyma, phloem, procambium, and starch sheath cells, imposing a radial auxin flux that results in radial growth. Using the protein synthesis inhibitor cycloheximide (CHX) or the fluorescent endocytic tracer FM4-64, we reveal that this expansion of the PIN3 cellular localization domain occurs because weight increase breaks the balance between PIN3 biosynthesis and removal, favoring PIN3 biosynthesis. Experimentation using brefeldin A (BFA) treatments or arg1 and arl2 mutants further supports this conclusion. Analyses of CRISPR-Cas9 lines for Populus PIN3 orthologs reveals that PIN3 dependence of weight-induced radial growth is conserved at least in these woody species. Altogether, our work sheds new light on how longitudinal and radial growth coordinate during stem development.

[Chemical constituents from stem bark of Aquilaria sinensis and their antibacterial activity against Helicobacter pylori].

The stem bark of Aquilaria sinensis(Thymelaeaceae), with the local name of "Li-Wa-Zi-Xing", is used in traditional Yi medicine for treating chronic gastritis and other diseases. However, its active ingredients remain currently unknown. In this study, Helicobacter pylori(Hp) is used in anti-bacterial experiments to test the active compounds derived from A. sinensis stem bark. Nineteen compounds were isolated from the stem bark of A. sinensis by column chromatography, high-performance liquid chromatography, recrystallization, etc. Aquilaridiester(1) is a new lignan. The other eighteen compounds were reported before, including docosyl caffeate(2), 6-hydroxy-2-[2-(4-methoxyphenyl)ethyl]-4H-1-benzopyran-4-one(3), qinanone A(4), 6-hydroxy-2-(2-phenylethyl)chromone(5), 6-hydroxy-2-[2-(3-hydroxy-4-methoxyphenyl)ethyl]-4H-1-benzopyran-4-one(6), 6-hydroxy-2-[2-(3-methoxy-4-hydroxyphenyl)ethyl]-4H-1-benzopyran-4-one(7), 6-hydroxy-2-[2-(3,4-dimethoxyphenyl)ethyl]chromone(8), 6-hydroxy-2-[(1E)-2-(4-hydroxy-3-methoxyphenyl)ethenyl]-4H-1-benzopyran-4-one(9), genkwanin(10), 5-hydroxy-2-(4-hydroxy-3,5-dimethoxyphenyl)-7-methoxy-4H-1-benzopyran-4-one(11), 3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone(12),(+)-syringaresinol(13), zhebeiresinol(14), aquilarin A(15), caruilignan D(16),(-)-ficusal(17), pistaciamide(18), and protocatechuic acid(19). The anti-bacterial results show that compounds 2-7, 10-11, and 13 have inhibitory activity against Hp. Among them, 6-hydroxy-2-(2-phenylethyl)chromone(5) and 6-hydroxy-2-[2-(3-methoxy-4-hydroxyphenyl)ethyl]-4H-benzopyran-4-one(7) have superior inhibitory effects on Hp to others, with the same minimum inhibitory concentration(MIC) of 6.25 µmol·L~(-1). The 2-(2-phenylethyl)chromones are the major active ingredients in A. sinensis stem bark.

Screening genotypes and optimizing ultrasonic extraction of phenolic antioxidants from Rheum ribes using response surface methodology.

The flowers and stems of Rhubarb (Rheum ribes L.) are known to contain effective antioxidant compounds that have potential antidiarrheal properties in traditional medicine. This study was conducted to screen various genotypes of Rhubarb for their phytochemical and antioxidant activity and optimize the extraction parameters using the response surface methodology (RSM). The study found high diversity among the different genotypes (G1-G13) in terms of their flowers and stems. The total phenolic content (TPC) in the flowers of R. ribes varied significantly, showing values between 9.80 and 81.53 mg GAE g-1 DW. In the stems, TPC ranged from 2.87 to 16.33 mg GAE g-1 DW. Similarly, the total flavonoid content (TFC) in the flowers ranged from 0.33 to 1.32 mg Qu g-1 DW, while in the stems, it was between 0.05 and 0.38 mg Qu g-1 DW. The antioxidant activity, indicated as µmol Fe2+ g-1 DW, varied from 7.42 to 59.87 in the flowers and from 0.14 to 15.99 in the stems. Hierarchical cluster analysis (HCA) identified five distinct clusters among the collected genotypes. Subsequent analysis of variance and principal components analysis (PCA) revealed that the flowers of G8 (G8F) from Tehran to Lavasan exhibited the highest total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity (FRAP). Given these findings, G8F was chosen for further optimization in the study. The RSM was designed based on a Box-Behnken design (BBD) to determine the optimal extraction conditions, including extraction temperature (30-80 °C), extraction time (5-15 min), and ethanol concentration (25-75%, ethanol to water, v/v). The responses measured were total phenolic content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging, and Ferric reducing/antioxidant power (FRAP) assays. The optimal extraction conditions for all responses or desirability indices were X1: 80 °C, X2: 15 min, and X3: 53.14%, which resulted in TPC (99.32 mg GAE.g-1 DW), TFC (3.00 mg Qu.g-1 DW), TAC (1.12 mg cyanidin-3-glucoside (Cy-g) g-1 DW), FRAP (110.22 µmol Fe+2/g DW), and DPPHsc (88.20%). The R2 values (0.91-0.99) indicated that the RSM models were acceptable.

Unveiling Fusaria mycoflora associated with natural occurrence of lisianthus wilt and stem rot in Central-highland Vietnam.

Wilt and stem rot (WSR) is an emerging syndrome threatening cut lisianthus (Eustoma russellianum) production in Lam Dong province, Vietnam. The disease was observed in all 13 inspected commercial lisianthus greenhouses across major lisianthus cultivation areas in Lam Dong, including Da Lat, Lac Duong, Don Duong, and Duc Trong, with incidence increasing with plant age, ranging from 7.5 to 32.4%. Infected plants displayed stunting, wilting, stem rot and blight, and dieback, with predominance of wilt and stem rot. The disease showed polycyclic behavior, with symptoms shifting from random or scattered in young plants to clustered patterns after the initial flower cutting. Forty-one Fusaria-like fungal isolates recovered from diseased lisianthus plants were identified as Fusarium vanleeuwenii (28 isolates), Neocosmospora solani (11 isolates), and F. annulatum (2 isolates) based on morphological observations and phylogenetic analysis of the internal transcribed spacer (ITS) region and translation elongation factor 1-alpha (TEF-1α) genes. The composition of Fusaria species varied across sites, with F. vanleeuwenii being consistently present. Pathogenicity tests confirmed that isolates of F. vanleeuwenii Li-Fo9511, N. solani Li-Fs4311, and F. annulatum Li-Fp3051 caused typical stem rot in in-vitro assays. In-planta assays showed wilting in seedlings starting two weeks post-infection, with a remarkable increase in disease incidence and severity between five and six weeks, particularly for F. vanleeuwenii Li-Fo9511. The pathogens were re-isolated and morphologically confirmed, fulfilling Koch's postulates. This is the first report of F. vanleeuwenii, N. solani, and F. annulatum as pathogens of lisianthus WSR in Vietnam, highlighting the need for effective control strategies.

Plant growth: The heavy matter of weight-induced plant stem thickening.

As plant stems grow taller and heavier, they adapt by promoting stem thickening. A new study shows that weight-induced radial growth is mediated by the auxin efflux transporter PIN3.

Standardization of silver nanoparticle synthesis: Photocatalytic application (immobilized with chitosan complex) with textile dyes and antibacterial activity against Staphylococcus aureus using banana pseudo stem.

The purpose of the study is to standardize the silver nanoparticle (BP-AgNPs) synthesis and its antibacterial activity and photocatalytic application with the selected dyes using the banana pseudo stem extract. "One-factor analysis (OFTA)" was carried out for the standardization of silver nanoparticle synthesis and nanoparticle-chitosan complex immobilization. The parameters were identified with plant quantity (20 g), silver nitrate concentration (1 mM), the ratio of plant extract and silver nitrate solution (2:8), pH (12), temperature (37 °C), dispersed light conditions, shaking conditions (120 rpm), and time (6 h) were analysed. The photocatalytic decolorization efficiency of the standardized BP-AgNPs (immobilized with chitosan complex) has shown 96.92% for methylene blue (10 ppm) at 3 h and 97.55% for safranin (100 ppm) at 15 h. The antibacterial activity for the synthesised BP-AgNPs was determined. MIC value of the BP-AgNPs was determined to be 15.62 µg. mL-1 for S. aureus. The synthesised BP-AgNPs treated with 0.5×, 1× and 2× MIC concentration (x = 15.62 µg. mL-1) showed decreased viable counts of S. aureus (99.6% at 2× concentration having viable count of 22.6 × 102 CFU. mL-1) at 24 h incubation when compared with the control culture. The structural characteristics of the BP-AgNPs were identified as spherical with SEM and the size was identified as 12.19 ± 1.62 nm with TEM and as 37.23 ± 17.89 nm with XRD. The parameters such as FTIR, Zeta potential, EDS further supports the nanoparticle synthesis with banana pseudostem extract. The current result suggested that, the silver nanoparticles (BP-AgNPs) synthesised using the extract of the banana pseudo stem could be used as an alternative source for dye decolorization and antibacterial activities.

Coordination between water relations strategy and carbon investment in leaf and stem in six fruit tree species.

The water relation strategy is a key issue in climate change. Given the difficulty of determining water relations strategy, there is a need for simple traits with a solid theoretical basis to estimate it. Traits associated with resource allocation patterns along a 'fast-slow' plant economics spectrum are particularly compelling, reflecting trade-offs between growth rate and carbon allocation. Avocado (Persea americana ), fig tree (Ficus carica ), mandarin (Citrus reticulata ), olive (Olea europaea ), pomegranate (Punica granatum ), and grapevine (Vitis vinifera ) were characterised in terms of iso-anisohydric strategy through stomatal behaviour, water potential at the turgor loss point (TLP), and hydroscape area. Additionally, the association of these metrics with leaf mass per area (LMA) and wood density (WDen) was explored. We observed high coordination between LMA and WDen, and both traits were related to metrics of water relation strategy. More anisohydric species tended to invest more carbon per unit leaf area or unit stem volume, which has implications for hydraulic efficiency and water stress tolerance. WDen and TLP were the most powerful traits in estimating the water relation strategy for six fruit species. These traits are easy to measure, time-cost efficient, and appear central to coordinating multiple traits and behaviours along the water relations strategies.

Augmenting the basis of lodging tolerance in wheat (Triticum aestivum) under natural and simulated conditions.

In wheat (Triticum aestivum ), canopy architecture, culm diameter and stem strength are the key providers of lodging tolerance. To better understand the lodging phenomenon and determine the best linked trait to lodging, a study of lodging resistance was conducted in both artificially-induced and natural lodging conditions. Various morphological, phenological and biochemical traits, such as acid detergent fibre, acid detergent lignin, cellulose and activity of lignin-synthesising enzymes (phenylalanine ammonia lyase and tyrosine ammonia lyase) were recorded. Anatomical features were also examined by light microscopy, using the Wiesner reaction. Genotype C306 demonstrated the highest susceptibility to lodging compared to other varieties due to its limited production of lignin-synthesising enzymes, as well as its taller plant height and narrower culms. The dwarf mutants (DM6 and DM7) have a stronger resistance against lodging because they have thick stems and a short plant canopy structure. The most suitable donors for lodging are semidwarf varieties (HD2967, DPW621-50, DBW88) because they have higher production of lignin and lignin-synthesising enzymes. Grey correlation analysis also confirmed the ability of these three genotypes to tolerate lodging. The genotypes studied were comprehensively ranked. The study also includes an effort towards the standardisation of lodging methodology under artificial conditions.

[Response of branch attributes of Larix kaempferi to climate variables]. / 日本落叶松枝条属性特征对气候变量的响应.

We established a mixed-effects model incorporating climatic factors for the base diameter and length of the primary branches of Larix kaempferi using stepwise regression, based on climatic data from a total of 40 standard plots located in Xiaolongshan, Gansu Province, Changlinggang Forest Farm in Jianshi County, Hubei Province, and Dagujia Forest Farm in Qingyuan County, Liaoning Province, as well as the data from 120 L. kaempferi sample trees. Additionally, we created prediction charts for the fixed effects portion of the optimal mixed model to determine the relationship between climatic factors and base diameter and branch length, to explore the differential response of L. kaempferi branches to climatic variables. The results showed that the base diameter mixing model with annual mean temperature and water vapor deficit and the branch length mixing model with annual mean temperature had the best fitting effect, with R2 of 0.6152 and 0.6823, respectively. Based on the fixed effects prediction chart of the mixed model, the overall basal diameter showed an increasing trend with the increases of relative branch depth. The average basal diameter size was in an order of young-aged plantation

Water retting process with hemp pre-treatment: effect on the enzymatic activities and microbial populations dynamic.

Proper retting process of hemp stems, in which efficient separation of cellulose fiber from the rest of the stem is promoted by indigenous microorganisms able to degrade pectin, is essential for fiber production and quality. This research aimed to investigate the effect of a pre-treatment dew retting in field of hemp stalks on the pectinolytic enzymatic activity and microbiota dynamic during lab-scale water retting process. A strong increase in the pectinase activity as well as in the aerobic and anaerobic pectinolytic concentration was observed from 14 to 21 days, especially using hemp stalks that were not subjected to a pre-retting treatment on field (WRF0 0.690 ± 0.05 U/mL). Results revealed that the microbial diversity significantly varied over time during the water retting and the development of microbiota characterizing the water retting of hemp stalks of different biosystems used in this study was affected by pre-treatment conditions in the field and water retting process and by an interaction between the two methods. Although at the beginning of the experiment a high biodiversity was recorded in all biosystems, the water retting led to a selection of microbial populations in function of the time of pre-treatment in field, especially in bacterial populations. The use of hemp stems did not subject to a field pre-treatment seems to help the development of a homogeneous and specific pectinolytic microbiota with a higher enzymatic activity in respect to samples exposed to uncontrolled environmental conditions for 10, 20, or 30 days before the water retting process. KEY POINTS: • Microbial diversity significantly varied over time during water retting. • Water retting microbiota was affected by dew pre-treatment in the field. • Retting of no pretreated hemp allows the development of specific microbiota with high enzymatic activity.

Seasonal Variability of Lipophilic Compounds in Oat (Avena sativa L.) Straw: A Comprehensive Chemical Study.

Oat straw, a residue of Avena sativa L., is recognized for its abundance in cellulose, hemicelluloses, and lignin. However, its potential as a source of lipophilic compounds within the framework of a biorefinery concept still remains unexplored. In this study, we conducted an extensive investigation into the content and chemical composition of the lipophilic compounds present in acetone extracts from oat straws of two distinct oat varieties, namely, Karen and Isaura. Furthermore, we examined their seasonal variability in content and composition in straw samples from oats planted in both spring and winter seasons. The extracted lipophilic compounds were predominantly composed of high molecular weight esters (26.0-38.1%), steroids (16.6-24.0%), n-fatty alcohols (10.9-20.7%), n-fatty acids (10.9-16.0%), and n-aldehydes (10.7-15.8%), with lower amounts of n-alkanes (1.1-3.0%), acylglycerides (2.3-3.8%), phytol and phytyl esters (0.6-2.9%), ß-diketones (0.1-2.5%), triterpenoids (0.9-1.2%), tocopherols and tocopheryl esters (0.2-0.7%), 2-hydroxy fatty acids (0.1-0.2%), and n-alkylresorcinols (0.1%). Notably, these different classes of compounds exhibited variations in their contents depending on the oat variety and the specific planting season. Of particular interest was the Karen variety, which presented significant amounts of high molecular weight esters, free fatty acids, and acylglycerols, especially when it was cultivated during the winter season. These findings underline the potential of oat straw as a valuable resource for lipid extraction within a biorefinery context and emphasize the importance of selecting the appropriate variety and season for optimal lipid yield.

Adjustment of storage capacity for non-structural carbohydrates in response to limited water availability in two temperate woody species.

Reserves of non-structural carbohydrates (NSC) stored in living cells are essential for drought tolerance of trees. However, little is known about the phenotypic plasticity of living storage compartments (SC) and their interactions with NSC reserves under changing water availability. Here, we examined adjustments of SC and NSC reserves in stems and roots of seedlings of two temperate tree species, Acer negundo L. and Betula pendula Roth., cultivated under different substrate water availability. We found that relative contents of soluble NSC, starch and total NSC increased with decreasing water availability in stems of both species, and similar tendencies were also observed in roots of A. negundo. In the roots of B. pendula, soluble NSC contents decreased along with the decreasing water availability, possibly due to phloem decoupling or NSC translocation to shoots. Despite the contrast in organ responses, NSC contents (namely starch) positively correlated with proportions of total organ SC. Individual types of SC showed markedly distinct plasticity upon decreasing water availability, suggesting that water availability changes the partitioning of organ storage capacity. We found an increasing contribution of parenchyma-rich bark to the total organ NSC storage capacity under decreasing water availability. However, xylem SC showed substantially greater plasticity than those in bark. Axial storage cells, namely living fibers in A. negundo, responded more sensitively to decreasing water availability than radial parenchyma. Our results demonstrate that drought-induced changes in carbon balance affect the organ storage capacity provided by living cells, whose proportions are sensitively coordinated along with changing NSC reserves.

Ethanol extract of Vanilla planifolia stems reduces PAK6 expression and induces cell death in glioblastoma cells.

Glioblastoma multiforme (GBM) is a malignant tumour with a poor prognosis. Therefore, potential treatment strategies and novel therapeutic targets have gained increased attention. Our data showed that the ethanol extract of Vanilla planifolia stem (VAS) significantly decreased the viability and the colony formation of GBM cells. Moreover, VAS induced the cleavage of MAP1LC3, a marker of autophagy. Further RNA-seq and bioinformatic analysis revealed 4248 differentially expressed genes (DEGs) between VAS-treated GBM cells and the control cells. Protein-protein interactions between DEGs with fold changes less than -3 and more than 5 were further analysed, and we found that 16 and 9 hub DEGs, respectively, were correlated with other DEGs. Further qPCR experiments confirmed that 14 hub DEGs was significantly downregulated and 9 hub DEGs was significantly upregulated. In addition, another significantly downregulated DEG, p21-activated kinase 6 (PAK6), was correlated with the overall survival of GBM patients. Further validation experiments confirmed that VAS significantly reduced the mRNA and protein expression of PAK6, which led to the abolition of cell viability and colony formation. These findings demonstrated that VAS reduced cell viability, suppressed colony formation and induced autophagy and revealed PAK6 and other DEGs as potential therapeutic targets for GBM treatment.

Identification and Functional Studies on the Role of PlSPL14 in Herbaceous Peony Stem Development.

Stem strength plays a crucial role in the growth and development of plants, as well as in their flowering and fruiting. It not only impacts the lodging resistance of crops, but also influences the ornamental value of ornamental plants. Stem development is closely linked to stem strength; however, the roles of the SPL transcription factors in the stem development of herbaceous peony (Paeonia lactiflora Pall.) are not yet fully elucidated. In this study, we obtained and cloned the full-length sequence of PlSPL14, encoding 1085 amino acids. Quantitative real-time PCR (qRT-PCR) analysis revealed that the expression level of PlSPL14 gradually increased with the stem development of P. lactiflora and was significantly expressed in vascular bundles. Subsequently, utilizing the techniques of virus-induced gene silencing (VIGS) and heterologous overexpression in tobacco (Nicotiana tabacum L.), it was determined that PlSPL14-silenced P. lactiflora had a thinner xylem thickness, a decreased stem diameter, and weakened stem strength, while PlSPL14-overexpressing tobacco resulted in a thicker xylem thickness, an increased stem diameter, and enhanced stem strength. Further screening of the interacting proteins of PlSPL14 using a yeast two-hybrid (Y2H) assay revealed an interactive relationship between PlSPL14 and PlSLR1 protein, which acts as a negative regulator of gibberellin (GA). Additionally, the expression level of PlSLR1 gradually decreased during the stem development of P. lactiflora. The above results suggest that PlSPL14 may play a positive regulatory role in stem development and act in the xylem, making it a potential candidate gene for enhancing stem straightness in plants.

YOLOv8-G: An Improved YOLOv8 Model for Major Disease Detection in Dragon Fruit Stems.

Dragon fruit stem disease significantly affects both the quality and yield of dragon fruit. Therefore, there is an urgent need for an efficient, high-precision intelligent detection method to address the challenge of disease detection. To address the limitations of traditional methods, including slow detection and weak micro-integration capability, this paper proposes an improved YOLOv8-G algorithm. The algorithm reduces computational redundancy by introducing the C2f-Faster module. The loss function was modified to the structured intersection over union (SIoU), and the coordinate attention (CA) and content-aware reorganization feature extraction (CARAFE) modules were incorporated. These enhancements increased the model's stability and improved its accuracy in recognizing small targets. Experimental results showed that the YOLOv8-G algorithm achieved a mean average precision (mAP) of 83.1% and mAP50:95 of 48.3%, representing improvements of 3.3% and 2.3%, respectively, compared to the original model. The model size and floating point operations per second (FLOPS) were reduced to 4.9 MB and 6.9 G, respectively, indicating reductions of 20% and 14.8%. The improved model achieves higher accuracy in disease detection while maintaining a lighter weight, serving as a valuable reference for researchers in the field of dragon fruit stem disease detection.

Comprehensive Comparison of Three Different Medicinal Parts of Eupatorium lindleyanum DC. Using the RRLC-Q-TOF-MS-Based Metabolic Profile and In Vitro Anti-Inflammatory Activity.

Eupatorium lindleyanum DC. (EL) is a traditional Chinese herb known for its phlegm-reducing, cough-relieving and asthma-calming properties. It is widely used for treating cough and bronchitis. However, preliminary experiments have revealed wide variations in the composition of its different medicinal parts (flowers, leaves and stems), and the composition and efficacy of its different medicinal parts remain largely underexplored at present. In this study, non-targeted rapid resolution liquid chromatography coupled with a quadruple time-of-flight mass spectrometry (RRLC-Q-TOF-MS)-based metabolomics approach was developed to investigate the differences in the chemical composition of different medicinal parts of EL. We identified or tentatively identified 9 alkaloids, 11 flavonoids, 14 sesquiterpene lactones, 3 diterpenoids and 24 phenolic acids. In addition, heatmap visualization, quantitative analysis by high-performance liquid chromatography (HPLC-PDA) and ultra-high-performance liquid chromatography-triple quadrupole tandem mass spectrometry (UPLC-MS/MS) showed particularly high levels of sesquiterpene lactones, flavonoids and phenolic acids in the flowers, such as eupalinolide A and B and chlorogenic acid, among others. The leaves also contained some flavonoid sesquiterpene lactones and phenolic acids, while the stems were almost absent. The findings of in vitro activity studies indicated that the flowers exhibited a notable inhibitory effect on the release of the inflammatory factors TNF-α and IL-6, surpassing the anti-inflammatory efficacy observed in the leaves. Conversely, the stems demonstrated negligible anti-inflammatory activity. The variations in anti-inflammatory activity among the flowers, leaves and stems of EL can primarily be attributed to the presence of flavonoids, phenolic acids and sesquiterpene lactones in both the flowers and leaves. Additionally, the flowers contain a higher concentration of these active components compared to the leaves. These compounds mediate their anti-inflammatory effects through distinct biochemical pathways. The results of this study are anticipated to provide a scientific basis for the rational and effective utilization of EL resources.

Chemical Composition and Antibacterial, Antioxidant, and Cytotoxic Activities of Essential Oils from Leaves and Stems of Aeschynomene indica L.

The objective of this study was to analyze the chemical composition and evaluate the biological capabilities of the essential oils (EOs) extracted from leaves and stems of wild Aeschynomene indica L. plants by the hydrodistillation method. By using GC-FID/MS, fifty-six and fifty-five compounds, representing 95.1 and 97.6% of the essential oils in the leaves and stems, respectively, were characterized. The predominant constituents of A. indica EOs were (E)-caryophyllene, linalool, viridiflorol, phytol, hexadecanoic acid, trans-verbenol, and α-guaiene. The antibacterial and synergistic activities of the EOs were assessed by microdilution and checkerboard assays. The results revealed a potent inhibition and bactericidal activity against Staphylococcus aureus and Bacillus subtilis with MICs of 0.312-0.625 mg/mL. When combined with traditional antibiotics, the essential oils of A. indica possessed excellent synergistic effects against all tested bacteria. Additionally, the EOs of A. indica leaves showed higher antioxidant activity (IC50 = 0.11 ± 0.01 µg/mL) compared to the stem oil (IC50 = 0.19 ± 0.01 µg/mL) using the ABTS radical scavenging assay. The in vitro cytotoxicity of EOs against human cancer cell lines HepG2, MCF-7, A-549, and HCT-116 was examined, and MTT assays showed that the EOs possessed a significant cytotoxic potential against MCF-7 breast cancer cells, with IC50 values of 10.04 ± 1.82 and 15.89 ± 1.66 µg/mL, and a moderate cytotoxic activity against other tested cells. In conclusion, the A. indica EOs could be considered a potential source of pharmacologically active compounds.

Identification and Analysis of the Mechanism of Stem Mechanical Strength Enhancement for Maize Inbred Lines QY1.

Enhancing stalk strength is a crucial strategy to reduce lodging. We identified a maize inbred line, QY1, with superior stalk mechanical strength. Comprehensive analyses of the microstructure, cell wall composition, and transcriptome of QY1 were performed to elucidate the underlying factors contributing to its increased strength. Notably, both the vascular bundle area and the thickness of the sclerenchyma cell walls in QY1 were significantly increased. Furthermore, analyses of cell wall components revealed a significant increase in cellulose content and a notable reduction in lignin content. RNA sequencing (RNA-seq) revealed changes in the expression of numerous genes involved in cell wall synthesis and modification, especially those encoding pectin methylesterase (PME). Variations in PME activity and the degree of methylesterification were noted. Additionally, glycolytic efficiency in QY1 was significantly enhanced. These findings indicate that QY1 could be a valuable resource for the development of maize varieties with enhanced stalk mechanical strength and for biofuel production.

The structural organization of the outer tissues in the gametophytic stem of the umbrella moss Hypnodendron menziesii optimizes load bearing.

MAIN CONCLUSION: The ultrastructural design and biochemical organization of the significantly thickened outer tissues of the gametophytic stem of Hypnodendron menziesii optimizes load bearing of the stem. Hypnodendron menziesii is a bryoid umbrella moss growing in high humid conditions on the forest floors of New Zealand. The erect gametophyte bears up to eight whorls of branches in succession, spreading across the stem that bears the heavy weight of branches with highly hydrated leaves. Our investigation using a combination of light microscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and TEM-immunolabeling techniques provided novel information on the structural design and biochemical organization of greatly thickened cell walls of epidermal, hypodermal, and outermost cortical tissues, comparing underlying thin-walled cortical tissues in the gametophytic stem. Probing into the ultrastructure of the cell wall architecture of these target tissues by TEM and SEM revealed the cell walls to display a multilamellar organization, in addition to demonstrating the presence of an electron-dense substance in the cell wall, presumably flavonoids. The pattern of distribution and concentration of rhamnogalacturonan, homogalacturonan, and heteromannan, as determined by immunogold labeling, suggests that it is the combination of structural and molecular design of the cell wall that may optimize the mechanical function of the epidermal, hypodermal, and outer cortical tissues. Statistical relationships between the overall thickness of epidermal, hypodermal, and outer cortical cell walls, the lumen area of cells and the percentage area of cell wall occupied in these tissues at different heights of the stem, and thickness of secondary cell wall layers (L1-L4/5) were explored. The results of these analyses unequivocally support the contribution of outer tissues to the mechanical strength of the resilient stem.