Phytochemical Analysis, Cytotoxic, Antioxidant, and Antibacterial Activities of Lichens.

BACKGROUND

Lichens present a complex symbiotic relationship between a filamentous fungus, photoautotrophic partner (algae or cyanobacteria), and bacterial community. . This study aimed at investigating the chemical composition and cytotoxic, antioxidant, and antimicrobial activities of acetone extracts of Moroccan (), and . The phytochemical analysis was carried out by HPLC-UV. The cytotoxic effect was assessed on human prostate cancer (22RV1), human colon carcinoma (HT-29), human hepatocellular carcinoma (Hep-G2), and Hamster ovarian cancer (CHO) cells lines by WST1 assay. The antioxidant power was assessed by DPPH and FRAP assays. The antibacterial effect was obtained using the broth microdilution method.

RESULTS

The findings of phytochemical analysis showed that the lichens studied possess interesting bioactive molecules such as physodalic acid, evernic acid, and usnic acid, as well as protocetraric acid. According to the American National Cancer Institute guidelines, the WST-1 test showed that all crude extracts did not show significant cytotoxic effects against all concerous cell lines, and IC values ranged from 42.30 to 140.24 g/mL. Regarding the antioxidant activity, extract showed the highest free-radical-scavenging ability (IC = 498.40 g/mL). The most potent antibacterial extract was recorded for extract with a minimum inhibitory concentration (MIC) ranging from 0.039 to 0.31 mg/mL.

CONCLUSION

In this research work, we report that the studied lichen extracts exhibit an important biological effect, supporting that lichens represent a hopeful source of original natural products for the research of new bioactive molecules having a pharmaceutical interest.