In vitro antimicrobial, anticancer, and apoptosis-inducing effects of the methanolic extract of Launaea mucronata

Abstract

Traditional medicine is widely used in the treatment and management of various ailments due to its low toxicity, low number of side effects and low cost. Many components of common fruits and vegetables play crucial roles as chemopreventive or chemotherapeutic agents. This study aimed to evaluate in vitro the antioxidant, cytotoxic and antimicrobial activities of Launaea mucronata’s methanolic stems and leaves extract. In this screening study, Launaea mucronata’s methanolic extracts showed remarkably antifungal activity against Candida albicans. The maximum zone of inhibition of the methanolic extract of Launaea mucronata leaves was detected against Proteus vulgaris with inhibition zones of 17.8 mm and 14.6 mm, respectively. 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay results showed high antioxidant activity for the extract almost comparable to that of ascorbic acid at 30 µg/ml, which indicates that it might potentially be developed into a successful antioxidant agent. Meanwhile, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was performed by screening the extract against HepG2 (Hepatocellular), A549 (Lung), HCT116 (Colon) and MCF7 (Breast) cancer cells and it was found that the extract exerted its highest activity against A549 cells with an IC50 value of 14.9 µg/ml. The extracts also shown lower cytotoxic activity against normal, healthy MRC-5 cells, with IC50 values of 204.83 g/ml for the stem extract and 412.4 g/ml for the leaves extract, respectively. This suggests that the extract is safe for normal, healthy cells, which is an important characteristic of any possible anticancer treatment. The antiproliferative and apoptosis activities of our selected plant showed that the extracts induced S-phase arrest and apoptosis in A549 cells. This high cytotoxic activity of the extract indicates that highly bioactive pure compounds could potentially be isolated from the extract in future studies and further developed into an anticancer agent specifically against lung cancer. Therefore, the current study has proven the potential of Launaea mucronata’s methanolic extract as a source of potent antioxidant and anticancer agent.