Analysis of Pharmacological Activities and Mechanisms of Essential Oil in Flowers of Citrus grandis 'Tomentosa' by GC-MS/MS and Network Pharmacology.

According to our research, the flowers from Citrus grandis 'Tomentosa' contain rich biologically active essential oil components, but the chemical components and relative pharmacological properties have not been systematically studied. Therefore, the study aimed to identify the essential oil components by GC-MS/MS and explore the pharmacological activity and mechanism of these essential oil components by a network pharmacology approach. Finally, GC-MS/MS analysis identified 43 essential oil components, which corresponded to 739 potential targets. GO analysis results showed that 12, 18, and 12 entries were related to biological processes, cellular components, and molecular functions, respectively. A total of 120 pathways were obtained based on KEGG analysis, of which the most important was the adenylate cyclase-inhibiting G protein-coupled acetylcholine receptor signaling pathway. The "active component-target-disease" network further demonstrated these essential oil components' potential efficacy against pain, tumors, neuropsychiatric diseases, eye diseases, and respiratory diseases, which were highly related to PPARA, GABRA1, PTGS2, and SLC6A2. Experimental validation confirmed that β-caryophyllene, a major constituent, dose-dependently inhibited the proliferation of HT29 and MCF-7 cells (0-320 μM). This study provides a reliable basis for elucidating the pharmacological activity of the essential oil components and related mechanisms, which is beneficial to the comprehensive utilization and development of Citrus grandis 'Tomentosa'.