The use of biomass feedstocks for producing high-value-added chemicals is gaining significant attention in the academic community. In this study, near-infrared carbon dots (NIR-CDs) with antimicrobial and bioimaging functions were prepared from Epigynum auritum branches and leaves using a novel green synthesis approach. The spectral properties of the synthesized NIR-CDs were characterized by ultraviolet–visible (UV-Vis) absorption and fluorescence spectroscopy. The crystal structures of the NIR-CDs were further characterized by high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), and X-ray diffraction (XRD). The NIR-CDs exhibited minimal toxicity, excellent biocompatibility, and high penetrability in both in vivo and in vitro environments, making them ideal luminescent probes for bioimaging applications. Moreover, the antimicrobial activity of NIR-CDs was tested against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), showing significant bacterial growth inhibition. The antimicrobial effect is likely attributed to the NIR-CDs disrupting the cell membrane integrity, leading to the leakage of the intracellular contents. Therefore, NIR-CDs hold promise as fluorescent bioimaging probes and antimicrobial agents.

To expound on the correlation between the microorganism communities and the formation of off-odour in Xuanwei ham, the microorganism communities and volatile compounds were investigated in the biceps femoris (BF) and semimembranosus (SM) of Xuanwei ham with different quality grades (normal ham and spoiled ham). The single molecule real-time sequencing showed that differential bacteria and fungi were more varied in normal hams than in spoiled hams. Headspace solid-phase microextraction–gas chromatography (HS-SPME-GC-MS) results indicated that aldehydes and alcohols were significantly higher in spoiled hams than those in normal hams (p < 0.05). The off-odour of spoiled hams was dominated by ichthyic, malodourous, sweaty, putrid, sour, and unpleasant odours produced by compounds such as trimethylamine (SM: 13.05 μg/kg), hexanal (BF: 206.46 μg/kg), octanal (BF: 59.52 μg/kg), methanethiol (SM: 12.85 μg/kg), and valeric acid (BF: 15.08 μg/kg), which are positively correlated with Bacillus cereus, Bacillus subtilis, Bacillus licheniformis, Pseudomonas sp., Aspergillus ruber, and Moraxella osloensis. Furthermore, the physicochemical property and quality characteristics results showed that high moisture (BF: 56.32 g/100 g), pH (BF: 6.63), thiobarbituric acid reactive substances (TBARS) (SM: 1.98 MDA/kg), and low NaCl content (SM: 6.31%) were also responsible for the spoilage of hams with off-odour. This study provided a deep insight into the off-odour of Xuanwei ham from the perspective of microorganism communities and a theoretical basis for improving the flavour and overall quality of Xuanwei hams.

This study investigated the chemical composition and anti-inflammatory effects of essential oils extracted from Citrus aurantium flower, Citrus sinensis, Brazilian Citrus sinensis, Citrus limon, Citrus bergamia, and Citri Reticulatae Pericarpium using steam distillation and gas chromatography-mass spectrometry (GC-MS). Their anti-inflammatory activities were assessed in LPS-stimulated RAW 264.7 cells. Among them, Citri Reticulatae Pericarpium essential oil (CRPEO) exhibited the most potent anti-inflammatory effects, with D-Limonene (76.51%), α-Pinene (2.68%), and Linalool (2.11%) as its primary constituents. The CCK-8 assay showed that the essential oil exhibited no cytotoxicity on HaCaT cells at a concentration of 50 μg/mL. CRPEO significantly preserved cell viability and reduced the production of pro-inflammatory mediators, including tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β, and nitric oxide (NO). Gene expression analysis via RT-qPCR further confirmed the downregulation of TNF-α, IL-6, IL-1β, and inducible nitric oxide synthase (iNOS) at the mRNA level. Network pharmacology and molecular docking studies were employed to identify α-Bulnesene as a key bioactive component of CRPEO and revealed that its principal target is the NLR Family Pyrin Domain-Containing 3 (NLRP3) inflammasome. These findings highlight the strong anti-inflammatory potential of CRPEO and suggest its promising therapeutic application for inflammation-related conditions.

Lymphoma is one of the malignant tumors that significantly threatens human health. Quadrigemine I, an indole alkaloid derived from the leaves of Psychotria pilifera, has been studied for its potential anti-tumor properties, but its mechanisms remain poorly understood. The CCK-8 assay was used to determine the cytotoxic effect of quadrigemine I on lymphoma cells. Flow cytometry was employed to analyze apoptosis and reactive oxygen species (ROS) levels in these cells. DNA damage was assessed by the comet assay, and the underlying mechanisms were investigated using RNA sequencing (RNA-seq) and real-time quantitative PCR (RT-qPCR). The anti-tumor activity of quadrigemine I was evaluated in tumor xenograft mice. Quadrigemine I suppressed lymphoma cell proliferation with an IC₅₀ of 0.46 µM. It induced apoptosis, promoted ROS generation, and caused DNA damage in tumor cells. RNA-seq analysis revealed that the significantly differentially expressed genes were notably enriched in the ErbB, p53, and apoptosis signaling pathways. RT-qPCR demonstrated altered expression levels of key genes in the aforementioned pathways. In vivo, quadrigemine I significantly inhibited tumor growth in xenograft mice by increasing apoptosis in tumor tissues, with reduced Ki-67 and Bcl-2 expression and elevated cleaved caspase-3 levels. Quadrigemine I may serve as a novel anti-tumor agent for lymphoma therapy.