Biodiversity and antimicrobial activity of intestinal fungi from three species of coral reef fishes

Abstract

Although intestinal microbiota plays crucial roles in fish digestion and health, little is known about intestinal fungi in fishes. This study investigated the intestinal fungal diversity of three coral reef fishes (Lates calcarifer, Trachinotus blochii and Lutjanus argentimaculatus) from the South China Sea using a culturable method. A total of 387 isolates were recovered and identified by sequencing their internal transcribed spacer sequences, belonging to 29 known fungal species. The similarity of fungal community in intestines of the three fishes verified the fungal colonization may be influenced by their surrounding environments. Furthermore, the fungal communities in different intestines of some fishes were significantly different, and the number of yeasts in hindgut was less than that in fore- and mid-intestine, suggesting that the distribution of fungi in fishes intestines may be related to the physiological functions of various intestinal segment. In addition, 51.4% tested fungal isolates exhibited antimicrobial activity against at least one marine pathogenic microorganisms. Notably, isolate Aureobasidium pullulans SCAU243 exhibited a strong antifungal activity against Aspergillus versicolor, and isolate Schizophyllum commune SCAU255 displayed extensive antimicrobial activity against four marine pathogenic microorganisms. This study contributed to our understanding of intestinal fungi in coral reef fish and further increasing the library of fungi available for natural bioactive product screening.

Metabolites Alteration and Antioxidant Activity of Gracilaria verrucosa After Fermentation Using Aureobasidium melanogenum MTGK.31

“…Aureobasidium melanogenum is a stress-tolerant yeast that can be found in many environmental conditions, including marine (Jiang et al, 2016;Sibero et al, 2022;Wang et al, 2014;Wu et al, 2022;Yanwisetpakdee et al, 2016). This yeast is equipped with a unique biosynthetic pathway to enhance its resilience by producing exopolysaccharides, enzymes, and bioactive compounds Jiang et al, 2016Jiang et al, , 2019aKang et al, 2022;Liu et al, 2018;Yanwisetpakdee et al, 2016).…”