Parentucellia viscosa (growing in Türkiye): Essential oil, phenolic composition, antimicrobial and lipase inhibition

The essential oil (EO) and phenolic constituents of Parentucellia viscosa L. were analyzed by GC-FID-MS and HPLC, respectively. A total of 20 volatile compounds were identified accounting for 99.97% in hydrodistillation. Monoterpenes (50.57%, 5 compounds) were the primary chemical class in the essential oil of P. viscosa. Limonene (44.02%) and 1-octen-3-ol (25.23%) were the major components in the essential oil of P. viscosa. The phenolic constituent analysis for the methanol extract of P. viscosa gave benzoic acid (0.97 mg/g) as the major compound. The antimicrobial activities of the EO and crude solvent (n-hexane, acetonitrile, methanol, and water) extracts of P. viscosa were screened in vitro against ten microorganisms. n-Hexane and the acetonitrile extracts of P. viscosa resulted in the best activity against Mycobacterium smegmatis with IC50 values of 19.2 µg/mL and 53.8 µg/mL, respectively. The highest lipase enzyme inhibition activity was detected in the n-hexane extract with 44.22±1.1628 µg/mL IC50 value.