Phytochemical screening and the antioxidant, antibacterial and antifungal activities of aqueous extracts from the leaves of Lippia triphylla planted in Morocco

Abstract

The principal objective of the present study is the qualitative and quantitative evaluation of phytochemical compounds, as well as the antibacterial, antifungal and antioxidant activities of the aqueous extract of Lippia triphylla planted in Morocco. The phytochemical screening revealed the presence of flavonoids and alkaloids with different concentrations as well as tannins with a higher content (0.27±0.02mg. Cat/ g extract). The antioxidant activity is carried out by the following methods: the DPPH test (IC-50 = 9.4 µg/ml higher than BHT (0.12 µg/ml)); the s-carotene decoloration test (the inhibition of oxidation of the aqueous extract (66.17%) was important than the negative control (13. 87%)); the reducing power test (FRAP) (detection of a low iron reducing power for the aqueous extract compared to Quercetin) and the total antioxidant capacity (CAT) (this test revealed an antioxidant capacity of 935.1±6.7 mg/g). On the other hand, the crude aqueous extract from the leaves of Lippia tiphylla showed varying degrees of antimicrobial and antifungal activity against four pathogenic bacteria and two yeasts by the agar diffusion method and the direct contact method. Minimum inhibitory concentration (MIC) values for E. coli 57, K. pneumoniae, P. aeruginosa, S. aureus, S. sereveseae and C. albicans were 50.71±5.42, 50.23±7.247, 50±2.04 12.5±0.517, 25±0.25 and 12.5±0.25 mg/ml respectively. Antimicrobial activity related to standard antibiotics was determined as a positive control.