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.

Objectives: The study aimed to investigate the antibacterial, in vitro anti-inflammatory and anti-acne properties of Patchouli essential oil (PEO). Methods: PEO components were quantified by gas chromatography–mass spectrometry (GC-MS). The antibacterial activity of PEO against Cutibacterium acnes (C. acnes) and Staphylococcus epidermidis (S. epidermidis) was evaluated via MIC detection and growth curve analysis. Bacterial membrane integrity was assessed by detecting intracellular substance leakage. LPS-induced RAW264.7 cells inflammatory models and heat-inactivated C. acnes-stimulated human epidermal keratinocytes (HaCaT) cells acne models were constructed to explore the in vitro anti-inflammatory and anti-acne activities of PEO by measuring the secretion levels of pro-inflammatory cytokines. Results: PEO primarily contained α-guaiene, patchouli alcohol and α-bulnesene. It showed potent antibacterial activity with an MIC of 0.50 mg/mL, inhibiting bacterial growth and disrupting cell membrane integrity. PEO significantly alleviated cell damage and reduced the secretion of TNF-α, IL-1β and IL-6 in two inflammatory cell models, and suppressed excessive keratinocyte proliferation. Conclusions: PEO exerts anti-acne effects via dual antibacterial and anti-inflammatory pathways. This work provides valid experimental evidence for the application of PEO as a novel natural anti-acne agent.