Impact of salinity stress on phytochemical profiles in Salvia officinalis

This study examines how varying salinity levels (5, 25, 50, 100, 150 and 200 mM NaCl) affect the phytochemical composition of Salvia officinalis. Using LC-MS analysis, we observed significant alterations in secondary metabolite production under salt stress. Monoterpenes, such as thujone and borneol, increased notably at 100-200 mM NaCl, indicating an upregulation of terpenoid biosynthesis as a protective response. Sesquiterpenes like Ledene and Humulene rose under moderate salinity (50-150 mM NaCl) but declined at 200 mM, possibly due to disrupted biosynthetic pathways. Diterpenes showed enhanced yields under moderate to severe stress, suggesting a role in augmenting plant resilience. Phenolic compounds, known for antioxidant properties, peaked at 100 mM NaCl, while flavonoid content decreased under higher salinity, implying suppression of their biosynthesis. Unsaturated fatty acids, including oleic and arachidonic acids, increased under stress levels of 150-200 mM NaCl, aiding in membrane stability. Additionally, under salt stress (50-200 mM NaCl), elevated levels of β-carotene, beta-sitosterol and malic acid were observed, supporting their roles in osmotic adjustment and mitigating oxidative stress. These findings underscore S. officinalis adaptive mechanisms to salinity through the accumulation of protective metabolites and metabolic adjustments. Future research should delve into the molecular mechanisms driving these changes to develop salt-tolerant crops and optimize sage cultivation in saline environments.