Antibiofilm effect of Tucum (Astrocaryum sp.) endosperm against Candida albicans

Abstract

Candida albicans is one of the most relevant human opportunistic pathogens and highly competent to build biofilms on vital and non-vital surfaces. Facing the escalating resistance of microorganisms to current antimicrobials and fungicides, the Amazonian biodiversity may bring raw material to the development of new antimicrobial drugs. Astrocaryum sp. is a regional fruit, consumed in natura or as ice creams and other local specialties. The seeds, however, are discarded and accumulate in the environment. The present study aimed to characterize the phytochemical composition of the endosperm and to evaluate the effect of its extracts on biofilm formation and eradication by C. albicans. The seeds were processed to obtain extracts in hexane and ethanol. Color chromatography procedure and thin layer chromatography were used, followed by a colorimetric phytochemical prospection to identify the major secondary metabolites. Microtiter plates were inoculated with C. albicans and incubated for 24 h in contact with the extracts or EDTA (positive control) to test the ability of preventing biofilm formation. To evaluate the biofilm eradication effect, the target strain was inoculated in the plates and incubated for 24 h previously to the addition of the extracts or EDTA. Both hexane and ethanol extracts demonstrated significantly higher effect than EDTA on Candida biofilm inhibition, highlighting hexane extract that achieved the lowest percentage of adhesion (9.46±0.9%). The chemical composition indicated mainly terpenes, phenols and antioxidant compounds. These results demonstrate a pharmaceutical potential of Astrocaryum sp. endosperm for future developments of antifungal drugs, thus contributing to reduce the environmental impact of this biological waste of Amazonia.