Due to sessile nature of plants, they are continuously exposed to fluctuating environmental conditions. In response, they have evolved several defense mechanisms, including the biosynthesis of secondary metabolites. These metabolites play crucial roles in stress tolerance, ecological interactions, and therapeutic efficacy. Biosynthesis of secondary metabolites is influenced by a complex interplay of abiotic factors such as elevation, temperature, soil moisture, and nutrient availability, as well as biotic pressures like microbial activity and herbivory. The research conducted on high altitude medicinal plants viz. Bergenia ciliata and Juniperus communis underscore the profound impact of environmental gradients on the phytochemical profiles. Juniperus communis L. needles collected from varying altitudes in Uttarakhand exhibited significant variation in total phenolic (up to 42.80 ± 1.398 mg GAE/g DW), flavonoid (2.47 ± 0.120 mg QE/g DW), and tannin content (8.21 ± 1.445 mg TAE/g DW). Antioxidant activities measured via DPPH, ABTS, and FRAP assays also varied with elevation, with the highest values recorded at sites above 4000 m. GC–MS profiling revealed 35 compounds, including communic acid and beta-Elemene, whose abundance was linked to altitude and soil characteristics such as pH and nutrient levels. Similarly, Bergenia ciliata, a perennial herb renowned for its therapeutic properties, demonstrated elevation-dependent variation in key bioactive compounds like bergenin and gallic acid. Methanolic rhizome extracts of B. ciliata analyzed via HPLC-PDA showed that higher elevations positively influenced bergenin concentration, while soil nitrogen had a negative correlation with total phenolics.

Climatic stressors such as increased temperature and radiation might have triggered enhanced biosynthesis of stress-related metabolites like tannins, particularly under low precipitation conditions. These findings collectively highlight that environmental factors, especially elevation, temperature, soil moisture, and nutrient dynamics play a vital role in the biosynthesis and accumulation of secondary metabolites in the plants.