LC-QTOF-MS analysis of phenolic compounds in Origanum compactum (Benth) aqueous extracts and assessment of their antioxidant potential
摘要
Origanum compactum Benth (Lamiaceae), known locally as ’’zaatar’’ one of five Origanum species endemic to Morocco, is relatively widely distributed in Morocco, particularly in the Rif region (Northern Morocco) and in the middle and high Atlas. This study aimed to investigate the chemical composition and antioxidant potential of aqueous extracts from the Origanum compactum (Benth) leaves. Qualitative profiling was carried out using ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). Furthermore, the antioxidant capacity was assessed through the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and the ferric reducing antioxidant power (FRAP) test. The results obtained showed an important antioxidant capacity with an IC50 of 31.32 ± 0.13 µg/mL for DPPH assay and 193.75 ± 1.47 AAE/g DM (expressed as ascorbic acid equivalent per g of dry matter) for FRAP assay. Through LC-QTOF-MS analysis, a total of 29 phenolic compounds were characterized across several chemical classes, among which salvianolic acids A and B, rosmarinic acid, and chlorogenic acid were identified as the major constituents. This study revealed that Origanum compactum (Benth) extracts contain various phenolic compounds and display potential as natural antioxidant agents for preventing oxidative stress.