PHYTOCHEMICAL ANALYSIS, ANTICANDIDAL AND ANTIDERMATOPHYTIC ACTIVITY OF STOECHOSPERMUM MARGINATUM AND SARGASSUM WIGHTII FROM THE GULF OF MANNAR COAST, SOUTH INDIA

The present study investigated the antifungal activity of crude extracts of two marine brown macroalgae, Stoechospermum marginatum and Sargassum wightii, obtained using five organic solvents: hexane, chloroform, ethyl acetate, acetone and methanol. Phytochemical screening was performed to identify the bioactive constituents responsible for their antifungal potential. The results revealed the presence of terpenoids, tannins, unsaturated sterols, and diterpenoids in the tested seaweed extracts. The antifungal activity was evaluated against selected fungal pathogens by determining the zone of inhibition, minimum inhibitory concentration (MIC), and minimum fungicidal concentration (MFC). The mean zones of inhibition produced by the algal extracts in agar diffusion assays ranged from 7.1 to 16.1 mm. The MIC values ranged from 250 to 1,000 µg/mL, whereas the MFC values ranged from 500 to 1,000 µg/mL, indicating varying degrees of antifungal activity among the extracts. Among the five solvent extracts, ethyl acetate extracts of both S. marginatum and S. wightii exhibited the highest antifungal activity against the tested fungal pathogens. Notably, the ethyl acetate extract of S. marginatum demonstrated pronounced inhibitory effects against Candida parapsilosis, Candida albicans, and Trichophyton rubrum. These findings suggest that marine brown macroalgae are promising sources of natural antifungal compounds. The observed activity may be associated with the presence of bioactive phytochemicals, highlighting their potential for further investigation in the development of algae-derived antifungal agents. Further studies involving compound isolation, structural characterization, and toxicity evaluation are required to establish their therapeutic potential.