IDENTIFICA TION OF ISOLATED YEASTS OF MUL BERRY MU ST AND ITS EVALUATION FOR POTENCIAL BIOTECHNOLOGICAL APPLICATION.

MARTINA, P. F.; FERREYRA, D.J.; ZIEGLER, T.E.

Foz do Iguaçu - Parana - Brasil

Congreso; 29° Congresso Brasileiro de Microbiologia; 2017

Sociedad Brasileira de Microbiologia

ABSTRACT: Mulberry fruits (Morus nigra) are important micro - habitats for thedevelopment of varietiesof yeast species in the  wild.The production of artisanal wines based on fermented juices ofmulberry fruit is a growing activity in the province of Misiones(Argentina). The objective ofthis work was to isolate, identify and characterize physiologicallyand molecularly nativeyeasts from fermented musts. Two yeasts (Mora01 IX and Mora01 X) were isolatedafter120 hours of incubation from a mulberry juice supplemented with 3%ethanol and 10%glucose. Molecular identification was performed by sequencing the 26SrDNA gene. The D1/D2 domain (approximately 600pb) was amplified using primersNL-1 (5´GCATATCAATAAGCGGAGGAAAAG) and NL-4 (5´-GGTCCGTGTTTCAAGACGG). Bothyeasts (Mora01 IX and Mora01 X) were identified as Saccharomycescerevisiae using the BLAST tool from the National Biotechnology Information Center (NCBI).Partial physiological characterization was performed on Glucose Saboraud medium (agar /broth), at 28 ° C and under static conditions. The fermentative capacity of the strains wasdetermined using theDurham bell technique, positive results were obtained for theproduction of gas (CO2). The tolerance for ethanol (7 to 10%) was evaluated by following the growth(optical density increase) at 660nm for 10 days, concluding that at higherconcentration of ethanol, 72 hours later the Mora01 IX strain reached the same values as the strain S.cerevisiae reference. Finally nutrient assimilation tests were carried out with usingselective media, and it was corroborated that both strains are not able to assimilate lactose as asource of carbohydrates and also lysine as a source of nitrogen. The results obtained in thisstudy may be useful for the selection of important yeasts in thebiotechnology industry.