<i>Astichopus multifidus</i> and <i>Holothuria floridana</i> from Yucatecan Coast as potential source of antifungal agents.

Introduction. Infections caused by pathogenic fungi present a persistent public health challenge. Marine invertebrates, such as sea cucumbers (holothurians), are recognized for their high protein content and various medicinal properties. They also serve as reservoirs of bioactive compounds. In the territorial waters of México, six sea cucumber species, including Astichopus multifidus, Isostichopus badionotus, and Holothuria floridana, are found along the Yucatán Peninsula. However, overexploitation threatens these species, potentially diminishing valuable sources of antimicrobial agents. Objectives. This study aims to evaluate the antifungal activity of organic extracts from A. multifidus and H. floridana against various fungal strains, using minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) assays. Materials and Methods. Organic extracts from A. multifidus and H. floridana were obtained and tested for antifungal activity using a microdilution method. The MIC and MFC values were determined against a panel of fungal strains, including Trichophyton rubrum, Aspergillus niger, and Cryptococcus neoformans. Extracts from Isostichopus badionotus were also evaluated. Results and Discussion. Approximately 50% of the extracts exhibited antifungal activity. Butanolic body extracts from A. multifidus and H. floridana displayed the lowest MIC values (15.6 µg/mL) against T. rubrum and A. niger, respectively. Additionally, these extracts demonstrated antifungal activity (31.2 µg/mL) against C. neoformans. In contrast, extracts from I. badionotus showed no activity. These results suggest that A. multifidus and H. floridana contain bioactive compounds with antifungal potential. Conclusions. The antifungal properties of A. multifidus and H. floridana highlight their potential as sources of novel antifungal agents. Their sustainable use could contribute to the development of new antifungals