Enhancing anti-inflammatory activity of Eucalyptus camaldulensis by upregulating secondary metabolites using suspension cultures techniques

Eucalyptus camaldulensis Dehn (Family Myrtaceae) is among the most prominent Eucalyptus species, extensively exploited for its anti-inflammatory efficacy. The present study undertakes a comparative phytochemical and pharmacological evaluation of leaf and tissue culture (callus) extracts and their corresponding volatile oils. Methanolic extracts from both plant sources were subjected to liquid chromatography–mass spectrometry (LC/MS), revealing 32 phytoconstituents in leaf extracts and 54 in callus extracts. Identified chemical classes included flavonoids, tannins, coumarins, and phenolic acids, with higher relative abundance in callus-derived extracts. Volatile oil analysis using gas chromatography–mass spectrometry (GC/MS) identified 58 compounds in leaf oil and 52 in callus oil. Quantitative profiling demonstrated a significant elevation in bioactive volatiles within callus oil: 1,8-cineole content showed a 2.1-fold increase compared to leaf oil, and both α-terpineol and sabinene exhibited approximately fourfold increases relative to leaf oil. Bioassays further indicated that callus extracts and volatile oils possess enhanced anti-inflammatory and antioxidant activities, exhibiting higher potency than leaf-derived counterparts. Remarkably, the anti-inflammatory activity of callus volatile oil exceeded that of the standard pharmaceutical agent indomethacin. These findings underscore the potential of in vitro tissue culture as a biotechnological tool for amplifying the yield and bioactivity of secondary metabolites in E. camaldulensis.