LC-ESI-MS characterization, antioxidant and antibacterial properties of various solvent extracts from Tricholaena teneriffae L

Organic extracts of aerial parts from Tricholaena teneriffae L. (Poaceae), a wild grass largely distributed in the arid regions, were screened for their phenolic compounds, antioxidant and antibacterial activities. LC-ESI-MS analysis resulted in the identification of 21 compounds distributed into 8 phenolic acids and 13 flavonoids. Phenolic acids represented 80% of the identified compounds in alcoholic extracts. In fact, quinic acid was the major compound (11.68 mg/g) followed by 4,5-di-O-caffeoylquinic acid (3.72 mg/g) measured in the methanol extract. The methanol extract presented the highest total antioxidant capacity (617 mg AAE/g) followed by the ethyl acetate extract (437 mg AAE/g). In addition, these extracts also showed the highest DPPH center dot scavenging activity as evidenced by the lowest IC50 values (IC50 = 0.10-0.11 mg/ml). The ferric reducing power was also measured and the better results (EC0.5 = 0.25-0.32 mg/ml) were obtained for ethyl acetate and ethanol extracts. The methanol extract (3 mg/well) was found to be the most potent (11-16 mm) againt most tested strains and Micrococcus luteus was the most vulnerable bacteria with MIC value of 2.5 mg/ml. (C) 2021 SAAB. Published by Elsevier B.V. All rights reserved.