Variety of Filamentous Fungi and Yeast Species Found on the White Sands of Crystal Beach in the Bahamas: Swimming with the Pigs

Abstract

Research on filamentous fungi in sand in tropical ecosystems is very limited. Every year many tourists visit the beach, especially in summer. Therefore, we want to continue learning about the variety of species of fungi and yeasts that live in the sand on the beach. Especially this beach that has pigs that swim with the people. The quality of the sand was analyzed. The following culture media were used: SDA, RBA, Mycosel and HardyCHROM^TM Candida. One gram of sand was weighed in triplicate and spread over the different media. The samples with the SDA, RBA and Mycosel media were incubated at 25 °C for 7 to 14 days. As for the samples with HardyCHROM^TM Candida, they were incubated at 35 °C for 48 hours. The colonies were isolated and counted. Macroscopic and microscopic analysis was used. Four genus were identified: Aspergillus sp., Penicillium sp., Candida sp., and Curvularia sp. The isolated yeast species were: Candida albicans, C. tropicalis, C. parapsilosis, C. krusei and C. glabrata. The filamentous fungal species were: Penicillium sp., Aspergillus sp., A. flavus, A. parasiticus and A. glaucus. The Candida genus was the most isolated. The average number of fungal and yeast colonies was 24 CFU/g. The quality of the sand was classified as average quality. Most of the isolates are fungi or yeasts of clinical interest. Many of these identified species are pathogenic, causing respiratory and skin diseases. Other species cause skin infections, respiratory allergies and risk of infection in immunosuppressed people. It is recommended to take measures to prevent these fungi from continuing to develop and thus avoid contamination of the sand.