Nucleobases, Nucleosides and Nucleotides Determination in Yeasts Isolated from Extreme Environments

Nucleobases, nucleosides and nucleotides can act as chemical markers and immunnostimulants. Ultra-high-performance liquid chromatography with electrospray ionization and quadrupole time of flight-mass spectrometry was used to determine bioactive compounds from different yeast species isolated from extremal marine environments, Yarrowia lipolytica, Sterygmatomyces halophilus, Kluyveromyces lactis and Debaryomyces hansenii. The selectivity of the detection system allowed the analytes to be unequivocally identified. Mass spectra were recorded in the positive ion mode and quantification was based on the protonated molecule. Retention times ranged between 0.8 and 2.8 min using a mobile phase composed by a mixture of methanol and (0.1% v/v) formic acid under gradient elution mode. For the analyzed yeasts, the nucleotides, nucleosides and nucleobases contents were quantified in three fractions: intracellular, free extracellular and RNA. The results showed that these yeasts are an excellent source of nucleobases, nucleosides and nucleotides; especially, adenosine (1497 mg kg(-1)) and guanosine (1445 mg kg(-1)) found in Y. lipolytica and D. hansenii, respectively. This novel source of innovative immunostimulant as food additive in aquaculture or other animal production systems remain to be evaluated.

Automated summary

This study used ultra-high-performance liquid chromatography with mass spectrometry to identify bioactive compounds from different yeast species. The results showed that these yeasts are a good source of nucleobases, nucleosides, and nucleotides, which have potential as immunostimulants for food additives.