Species‐Specific Phytometabolite Composition of <i>Ocimum</i> (Holy Basil) Inflorescences Underlies Differential Biological Activities

This study aimed to systematically compare the inflorescence of Ocimum tenuiflorum L. (OTI) and Ocimum gratissimum L. (OGI), focusing on phytochemical composition and anti-inflammatory potentials, thereby providing the foundation for phytopharmaceutical and nutraceutical applications. The nonvolatile phytoconstituents of OTI and OGI were profiled using ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC/MS-QToF). Volatile constituents were analyzed using headspace gas chromatography-tandem mass spectrometry (HS-GC-MS/MS) and conventional gas chromatography-mass spectrometry (GC-MS/MS). High performance liquid chromatography was used for quantification of marker compounds including rosmarinic acid, ursolic acid, caffeic acid and 7-O-glucoronide, in OTI and OGI. The anti-inflammatory activity of both inflorescences was also evaluated by using liposaccharides (LPS) stimulated human THP-1 cell line. Comparative metabolomic analysis revealed significant interspecies variations. OGI displayed higher concentrations of most of the marker phytoconstituents, except caffeic acid, whereas OTI exhibited greater abundance of essential oils. Several metabolites including salviaflaside, suavissimoside R1, tangshenoside-1 and tricoumaroyl spermidine were also observed first time in both species. Both OTI and OGI demonstrated strong anti-inflammatory activities in THP-1 cells, though with distinct activity profile. These findings highlight the chemical diversity and biological potentials of OTI and OGI, with relevence in nature inspired drug designs.