Characterization of hepatoprotective metabolites from Artemisia annua and Cleome droserifolia using HPLC/PDA/ESI/MS–MS

The hepatoprotective activities of two traditionally used plants, Cleome droserifolia (Forssk.) Delile, Cleomaceae, and Artemisia annua L., Asteraceae, were recently reported. However, the biologically active metabolites responsible for this activity were not identified. The aqueous extract of C. droserifolia aerial parts, and the polar fraction of A. annua leaves were screened for their antioxidant activities using the 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) assay. The in vitro viability of HepG-2 cells treated with CCl4 and the extracts were assessed by MTT assay. The effects of the extracts on the liver enzymes and the total soluble protein in CCl4-intoxicated HepG-2 cells were investigated. An HPLC/PDA/ESI/MS–MS based analysis was carried out for extract of C. droserifolia and polar fraction of A. annua. Both exhibited pronounced free radical scavenging activities (86 and 83%, respectively). Both showed a significant increase in cell viability: 86.43% for the extract of C. droserifolia and 79.32% for polar fraction of A. annua. Only the extract of C. droserifolia (39.6 ± 5.41 and 20.4 ± 6.91 IU/dl, respectively) and polar fraction of A. annua (40.8 ± 2.14 and 24.5 ± 3.11 IU/dl, respectively) restored the levels of liver enzymes (aspartate transaminase and alanine transaminase, respectively) compared to the CCl4 intoxicated group (87.5 ± 4.34 and 34.1 ± 8.12 IU/dl, respectively) and other herbal extracts. More than fifty phenolic secondary metabolites were identified in the extracts under investigation. The significant hepatoprotective activities of both extracts seemed to be strongly connected to their content of hydroxycinnamoyl quinic acids and flavonoids. Keywords: Herb, Traditional, HPLC/PDA/ESI/MS–MS, Hepatoprotective, HepG-2, Antioxidant