Correlation Between Environmental Factors and the Chemical Composition and Bioactivity of Juniperus przewalskii Essential Oil in the Northeastern Qinghai-Tibetan Plateau.

Juniperus przewalskii Kom. is a dominant tree species endemic to the Tibetan Plateau, primarily found in its Northeastern region. The needles of this species possess notable antiemetic, antibacterial, anti-inflammatory, and antitussive properties and have been extensively used in traditional Tibetan medicine. In this study, we analyzed the chemical composition and bioactivity of essential oils (EOs) from seven populations of J. przewalskii and examined the influence of environmental factors. Gas chromatography-mass spectrometry (GC-MS) analysis identified 60 compounds across the seven regions. The main compounds included α-pinene (6.33%-11.38%), sabinene (5.58%-16.59%), sylvestrene (4.49%-8.28%), and γ-terpinene (1.02%-3.27%). Significant variation in EO composition among sites was linked to annual average temperature (AAT), annual average precipitation (AAP), total potassium (TK), available phosphorus (AP), and soil organic matter (SOM). Levels of α-pinene, cis-thujopsene, and α-cadinol were positively correlated with longitude, AAT, and AAP but negatively correlated with altitude. Notably, sabinene content increased with altitude and TK but decreased with longitude, AAT, and AAP. The EO extracted from XH demonstrated superior qualities, including a high yield, rich content of major compounds, and robust antioxidant and antimicrobial activities. These findings suggest that J. przewalskii EOs may have potential for future applications in cosmetics, perfumes, and other value-added products, pending further targeted evaluation. This study provides insights into potential optimal cultivation zones and strategies for improving EO quality in J. przewalskii, thus offering valuable insights for resource utilization and the development of flavor and fragrance products.