The protracted formation time of bioactive metabolites in rare woody medicinal plants limits both wild resource conservation and near‑term economic returns from cultivation. Syringa pinnatifolia is an endangered medicinal shrub from cold and arid regions of Inner Mongolia, accumulating pharmacologically valuable lignans and the sesquiterpenoid zerumbone. Despite medicinal progress, neither large-scale artificial cultivation nor early quality induction has been established for this endangered species. We subjected two‑year‑old cultivated plantlets to four watering regimes, with metabolomic, transcriptomic and physiological profiling of peeled stems. Our results indicated that water‑deficit (Drought, DR) and alternating wet/dry (AW/D) redirected metabolism towards accumulation of lignans and zerumbone, whereas well‑watered conditions (MW and RW) favored phenolics, sesquiterpenoids and flavonols. Notably, AW/D induced the broadest lignan spectrum and elevated zerumbone to levels approaching those of 30-year-old wild stems, but also increased specific lignan glycosides beyond the wild benchmark, and exhibited a higher relative yield of functional compounds per unit area. Transcriptomic analysis indicated that these metabolic shifts were accompanied by transcriptional changes of phenylpropanoid and terpenoid pathways, with AW/D associated with higher expression of downstream lignan-assembly genes (DIR) and the zerumbone synthase TPS8–1, while DR was associated with higher expression of TPS8–2 and CYP76S105–1. Co-expression analysis suggested that WRKY and MYB transcription factors may participate in these responses. Our results demonstrate that an appropriate watering regime can efficiently induce target compound profiles in plantlets in common-garden experiment even far away from native habitat, offering a sustainable alternative to wild harvesting for this protected species, and providing a potential strategy to establish upstream production capacity and reduce the payback period in cultivation.
The increasing prevalence of antimicrobial-resistant wound infections and the demand for multifunctional biomaterials have motivated the development of plant-based nanofibrous platforms. This study reports the fabrication, characterization, and comprehensive biological evaluation of multifunctional electrospun polyvinyl alcohol (PVA) nanofibers embedded with thyme (Thymus) extract at various loading rates (T1%, T5%, T10%, and T20%). The research evaluated the nanofibers across six critical biological domains: antimicrobial activity, biofilm inhibition, microbial cell viability, antioxidant capacity, surface antimicrobial performance, and antidiabetic activity. The results revealed a significant concentration-dependent enhancement in all tested areas. The T20%/PVA nanofibers exhibited the strongest performance, showing high antimicrobial activity (Minimum Inhibitory Concentration (MIC)) values as low as 32 mg/L and potent surface antimicrobial activity with inhibition rates reaching 98.72% for Staphylococcus aureus . Biofilm inhibition assays and microbial cell viability tests further confirmed that the nanofibers effectively disrupted the structural integrity and metabolic activity of both Escherichia coli and Pseudomonas aeruginosa . Additionally, the high phenolic content of the extract imparted significant antioxidant activity, reaching a 92.64% DPPH scavenging rate. Finally, the nanofibers demonstrated strong antidiabetic activity by inhibiting α-amylase (84.13%), exhibiting performance comparable to the commercial drug acarbose. The results show that thyme-embedded PVA nanofibers are excellent multifunctional biomaterials that have great potential for application in wound dressing, antimicrobial coating and therapeutic applications. It should be noted that PVA is water-soluble and crosslinking treatment was not performed for this study. Hence, additional studies of the water stability, crosslinking methods, and biocompatibility are needed to prove their feasibility for the use as wound healing agents.
Sclerotinia stem rot (SSR) is a devastating disease caused by the necrotrophic fungus Sclerotinia sclerotiorum , it caused 20–80% yield loss in rapeseed every year. Host-Induced Gene Silencing (HIGS) represents a promising strategy to improve SSR resistance due to the scarcity of highly resistant rapeseed genotypes. However, the lack of robust targets remains a major bottleneck for the application of HIGS. This study presented a novel strategy to efficiently discover the HIGS targets using an antifungal drug caspofungin (CFN). It was found that CFN treatment not only modified rapeseed architecture but also suppressed S. sclerotiorum growth and pathogenicity. Transcriptomic analysis revealed that CFN significantly suppressed amino acid metabolism pathways in Sclerotinia sclerotiorum , while WGCNA identified SsFKS1 as a key gene associated with the CFN-induced inhibition of fungal growth and pathogenicity. The SsFKS1 knockout mutant failed to produce sclerotia and showed impaired mycelial growth, following analysis discovered that the pathogenicity of mycelium was completely abolished. It is confirmed that the dsRNA ( dsfks1 ) targeting to the domain of SsFKS1 inhibited the growth and pathogenicity of mycelia. Furthermore, HIGS-mediated silencing of SsFKS1 significantly enhanced resistance to SSR in transgenic rapeseed. Our findings demonstrated that clinical antifungals could be used as powerful and convenient tools for identifying potential HIGS targets, providing both a promising gene resource for SSR-resistant breeding and a broadly applicable strategy for protecting crops against fungal pathogens.
The development of bio-based wood adhesives exhibiting robust bonding performance, excellent water resistance, and long-term mold resistance is critical for the sustainable manufacturing of wood-based panels. In this work, a formaldehyde-free adhesive was developed by crosslinking oxidized camellia meal (OCM), a non-edible agricultural residue, with hyperbranched polyurea (HBPU). Spectroscopic and structural analyses supported the formation of a crosslinked network involving imine and amide linkages and hydrogen-bonding interactions, which improved the hydrolytic and thermal stability of the cured adhesive. At an HBPU loading of 20 wt%, the OCM–HBPU adhesive achieved shear strengths of 1.22 MPa under dry conditions, 1.15 MPa after immersion in water at 63 °C, and 1.14 MPa after boiling-water treatment. Particleboards bonded with the optimized adhesive exhibited an internal bond strength of 1.70 MPa, a modulus of rupture of 22.22 MPa, and a modulus of elasticity of 3232.60 MPa. No visible mold growth was observed on the adhesive samples over 60 days at 30 °C and 95% relative humidity without added synthetic biocides. A preliminary 21-day soil-based assay showed no obvious inhibition of mung bean germination or seedling growth under the tested conditions. These results support the potential of OCM–HBPU as a formaldehyde-free, water-resistant, and mold-resistant adhesive for wood-based panels.
Water and nitrogen are key environmental factors that influence wood formation in trees, a process that depends largely on lignin deposition in the cell wall. However, regulation of lignin biosynthesis at the molecular level by water–nitrogen coupling in conifers remains largely unknown. In this study, three-year-old Larix principis–rupprechtii seedlings were subjected to three water regimes and three nitrogen levels. Growth measurements, anatomical observations, cell wall component assays, and enzyme activity analyses were integrated with transcriptomic and metabolomic profiling. Drought emerged as the primary factor limiting seedling growth and wood formation, and its inhibitory effect intensified with increasing water deficit. Nitrogen only modulated growth within the limits set by water availability. Lignin content declined progressively with increasing drought intensity, accompanied by reduced tracheid wall thickness, whereas cellulose and hemicellulose contents remained unchanged. Integrated omics analyses identified 6827 differentially expressed genes and 2122 differentially accumulated metabolites, with the phenylpropanoid pathway significantly associated with both lignin content and tracheid wall thickness. Within this pathway, POD93 emerged as a key responsive node at the terminal polymerization step of lignin biosynthesis, and its transcript levels dropped sharply under drought, with this decline further exacerbated by reduced nitrogen supply. Co–expression analysis and promoter cis-element prediction pinpointed MYB53 as a candidate regulator of POD93; subsequent yeast one-hybrid and dual-luciferase assays confirmed that the upstream transcription factor (TF) MYB53 activates POD93 transcription. Collectively, these findings establish a regulatory pathway linking water–nitrogen signals, a MYB TF, phenylpropanoid pathway genes, and the association between lignin content and tracheid wall thickness in a conifer species. Our work provides mechanistic insights into environment-dependent secondary metabolism and offers candidate gene resources for wood quality improvement in L. proncipis-rupprechtii.
