Antituberculosis Effect of Polyclium Indicum Ascidian Against Three Mycobacterium Strains

Abstract

Introduction: Polyclinum indicum, a marine ascidian, has gained attention for its potential anti-tuberculosis (TB) properties. Tuberculosis, caused by Mycobacterium tuberculosis and related strains, remains a global health challenge due to rising drug resistance. Ascidians are known to produce bioactive compounds with antimicrobial properties, but their role in TB treatment remains underexplored.

Objectives: This study evaluates the anti-tuberculosis activity of methanolic extracts of Polyclinum indicum against M. tuberculosis H37Rv, SIT777, and SIT26 strains using the resazurin microtiter assay (REMA).

Methods: Polyclinum indicum samples were collected from the Rameshwaram Gulf Biosphere Reserve, extracted with methanol, and tested for antimycobacterial activity. REMA was used to determine the minimum inhibitory concentration (MIC). Rifampicin was used as a positive control. Extract dilutions (0.78–100 µg/mL) were tested against the mycobacterial strains, and MIC values were established based on colorimetric changes in resazurin.

Results: The methanolic extract exhibited moderate antitubercular activity with MIC values of 11.39 µg/mL for H37Rv, 16.14 µg/mL for SIT777, and 15.2 µg/mL for SIT26. These values were higher than rifampicin (2.4–4.8 µg/mL), indicating that while the extract demonstrated antimycobacterial potential, its efficacy was lower than the standard drug.

Conclusions: Polyclinum indicum exhibits moderate anti-TB effects, warranting further investigation into its bioactive compounds. Future studies should focus on compound isolation, mechanistic pathways, toxicity assessment, and potential synergistic effects with existing TB therapies.