Zhaohua Shi

The root bark of Morus alba L. is commonly used as a natural antioxidant; however, its active constituents and underlying molecular mechanisms remain unclear. In this study, a bioactivity-guided isolation approach was employed to identify antioxidant substances from the root bark of Morus alba L. and to investigate their protective effects against oxidative damage in HaCaT cells. Using techniques such as silica gel column chromatography and semi-preparative HPLC, combined with NMR and HR-ESI-MS analysis, 22 compounds were isolated and identified from the dichloromethane extract of Morus alba L. root bark, including Diels–Alder adducts, flavonoids, and benzofurans. Among them, compounds 1 and 2 are new compounds, while compounds 12 and 16 were isolated from this plant for the first time. Bioactivity screening revealed that Kuwanon A (compound 17) exhibited significant cytoprotective effects in an H₂O₂-induced HaCaT cell injury model, effectively scavenging intracellular reactive oxygen species (ROS), restoring mitochondrial function, and enhancing the activities of antioxidant enzymes such as SOD and GSH. Further studies indicated that H₂O₂ induced ferroptosis in HaCaT cells, characterized by abnormal Fe²⁺ levels, lipid peroxidation, and elevated levels of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α). Kuwanon A significantly ameliorated these pathological changes. Consistently, ELISA and Astral DIA quantitative proteomics analyses demonstrated that Kuwanon A specifically upregulates the expression of the sulfurtransferase NFS1, thereby promoting the expression of the core antioxidant enzyme GPX4 and the iron storage protein ferritin-H, collectively inhibiting ferroptosis. This study elucidates that Kuwanon A is a key active component responsible for the antioxidant and anti-inflammatory effects of Morus alba L. root bark, and its mechanism is closely associated with regulating the NFS1-mediated ferroptosis defense pathway.

The petals of Magnoliaceae plants have been used in traditional Chinese cuisine for centuries. This study represents the first comprehensive comparison of the primary odour components and sensory characteristics of Magnolia wufengensis (MAW) and four other Magnolia species. Using GC × GC‐TOF MS and ROAV analysis, we systematically investigated the volatile compound profiles and processing stabilities of the samples. The results revealed that MAW exhibits a distinct aldehyde‐rich aroma profile, with key odorants including 2‐nonenal, heptanal, 2‐pentylfuran, and (E)‐2‐octenal (ROAV ≥ 1), which collectively contribute to its ‘fresh‐sweet‐fruity’ sensory signature. Comparative analysis showed that freeze‐drying significantly surpassed shade‐drying in preserving key aroma compounds, demonstrating a 6.7‐fold higher retention rate of 2‐nonenal and effectively inhibiting off‐flavour formation compared with shade‐drying. These findings elucidate the chemical basis of aroma diversity and confirm the advantages of cryopreservation for fragrance retention, providing a scientific foundation for the application of Magnolia species in the food industry.

The Dof (DNA binding with one finger) transcription factor family is a plant-specific group of transcription factors that play critical roles in plant growth and development, stress response, and the regulation of secondary metabolism. Prunella vulgaris (P. vulgaris) has attracted considerable attention due to its medicinal value, with rosmarinic acid being one of its key bioactive components. However, the systematic identification of the Dof transcription factor family in P. vulgaris and its regulatory role in rosmarinic acid biosynthesis remains poorly understood. In this study, based on the whole-genome data of P. vulgaris, we identified 48 Dof transcription factor genes distributed across 14 chromosomes using bioinformatics approaches. Physicochemical analysis revealed that the encoded proteins have molecular weights ranging from 15,482.44 to 55,875.53 Da, amino acid lengths between 142 and 509, and theoretical isoelectric points from 4.84 to 10.2. All proteins were predicted to be hydrophilic and localized in the nucleus. Phylogenetic analysis classified them into four subfamilies, and multiple sequence alignment confirmed that all members contain a conserved C2-C2-type zinc finger domain. Analysis of cis-regulatory elements in the promoter regions identified numerous elements related to light responsiveness, hormone response, and development. Transcriptomic expression profiling demonstrated distinct tissue-specific expression patterns of Dof genes, with some showing high expression in spikes and seeds. Correlation analysis between gene expression and rosmarinic acid content identified three candidate genes potentially involved in the regulation of rosmarinic acid biosynthesis, which were further validated by RT-qPCR. Moreover, protein–protein interaction network predictions indicated 242 interactions among 23 Dof proteins. This study provides the first systematic identification of the Dof transcription factor family in P. vulgaris, offering important insights into the transcriptional regulation of rosmarinic acid biosynthesis and presenting potential genetic targets for enhancing rosmarinic acid production through genetic engineering.

Anthracnose is an emerging threat to Epimedium sagittatum, a cornerstone species in traditional Chinese medicine; however, its etiology in biodiversity hotspots remains unresolved. In this study, we comprehensively identified the anthracnose pathogens affecting E. sagittatum in China's Shennongjia Forest District. Through a combination of multi-locus phylogenetic analyses (based on ITS2, GAPDH, TUB2, and ACT sequences) and pathogenicity assays, we identified Colletotrichum fructicola as the primary causal agent. Beyond pathogen identification, we found that infection triggers a sharp decline in key flavonoids (epimedin A, B, and C; icariin; and icaritin). Concurrent rhizosphere microbiome profiling revealed a shift toward dysbiosis, characterized by the depletion of beneficial taxa (e.g., Annulohypoxylon, Rhizophagus, Bradyrhizobium, and Pseudomonas) and an enrichment of opportunistic ones (e.g., Rhizoclosmatium, Fusarium, and Coccidioides). Strikingly, in detached leaf assays, the plant-derived phenolic compound carvacrol inhibited the growth of C. fructicola by 86.7%. Together, our findings not only identify a pathogen of concern but also delineate a disease progression pathway primarily driven by metabolic reprogramming of the host (flavonoid depletion) and concomitant rhizosphere dysbiosis. We also propose carvacrol as a potent biocontrol agent. This work addresses critical knowledge gaps in medicinal plant pathology and proposes an eco-sustainable strategy for managing anthracnose.