Screening of Secondary Metabolites and Semi-Synthetic Analogues of Ramalina leiodea (Nyl.) Nyl. against Free Radicals, Inflammation and Cancer Cell Lines

The objective of the present study is to evaluate the pharmacological actions of earlier reported metabolites (1-5), and semi-synthetic analogs (4a-e) from acetone extract of Ramalina leiodea. The Acetone extract of Ramalina leiodea were screened for antioxidant, anti-inflammatory, anticancer, and acute toxicity studies. The antioxidant results exhibited that compound 4e showed effective inhibitory ability against ferric ions, 2,2-diphenyl-1-picrylhydrazyl and superoxide free radicals with 50 % inhibition value of 28.50, 27.0, and 25.0 mu g/ml, respectively. Also, among all the samples, 4e revealed good inhibition of albumin denaturation of 105 mu g/ml (IC50 value). Additionally, the median lethal dosage of acetone extract of Ramalina leiodea was observed to be above 2000 mg/Kg body weight. Also, the in vivo anti-inflammatory studies of acetone extract of Ramalina leiodea exhibited a noticeable reduction of edema in rat paw at both low and high dosage when compared to indomethacin. From the sulforhodamine B assay, it is concluded that 2 and 4b displayed a noteworthy degree of specificity against tested series of cell lines. On the other hand, all tested samples displayed a low degree of specificity against normal cells. To conclude, Ramalina leiodea could be the best source for bioactive agents for the management of oxidative stress, inflammation, and cancer.