Influence of 60Co Irradiation on the Volatile Organic Compounds of Cnidii Fructus

Background/Objectives: As a traditional Chinese medicinal herb, Cnidii Fructus is widely used in clinical practice. Its volatile organic compounds (VOCs) are closely related to its antipruritic effect and insecticidal properties. Due to the susceptibility of this medicinal herb to mold contamination, adopting appropriate sterilization measures is of great significance for its storage. 60Co irradiation is widely used for this purpose due to its various advantages. Methods: This study employed Gas Chromatography–Ion Mobility Spectrometry (GC-IMS) combined with multivariate statistical analysis to systematically investigate the influence of different 60Co irradiation doses (0, 3, 6, 9 kGy) on the VOCs of Cnidii Fructus and associated metabolic regulatory mechanisms. Results: A total of 115 VOCs were tentatively identified. Statistical analysis revealed dose-dependent effects: 3 kGy irradiation caused the least compositional perturbation, best preserving original chemical characteristics; 6 kGy induced more pronounced compositional changes; and 9 kGy triggered substantial chemical composition reconstruction. Differential metabolite enrichment analysis indicated that medium and high doses of irradiation primarily perturbed central carbon metabolic pathways, including pyruvate metabolism, glycolysis/gluconeogenesis, and glyoxylate and dicarboxylate metabolism. Key differential components were tentatively identified (e.g., α-Thujone, α-Pinene, β-Pinene) that possess pharmacological activities closely associated with the traditional efficacy of Cnidii Fructus. Conclusions: When the irradiation dose is 3 kGy, the VOCs profile of Cnidii Fructus is most similar to that of the non-irradiated control group, suggesting that its compositional profile may be closer to that of traditional high-quality medicinal materials. Meanwhile, the differential metabolites and core metabolic pathways identified in this study can provide a chemical reference for the quality control of irradiated Cnidii Fructus. The findings provide a theoretical basis and technical support for the rational application of 60Co irradiation sterilization in the processing of Chinese medicinal materials and their powders.