Biodiversity Study by Dependent and Independent Culture Techniques of a Winery located in a Re-emerging Winegrowing Region of Argentina

Abstract

Argentina ranks among the "top 10" countries globally in the wine industry, being the 7th largest wine producer, the 8th exporter, and the 9th consumer. Traditional wine regions have been extensively studied using culture-dependent techniques, and to a lesser extent, by culture-independent techniques. However, regions that have been marginalized due to political, economic, and social reasons are now recognized as re-emerging in terms of productivity but remain poorly studied or unstudied. The province of Buenos Aires is identified as a re-emerging region of socio-economic and cultural interest due to its growth in viticulture over the last 20 years. The objective of this study was to analyze, using both culture-dependent and culture-independent techniques, a sample of 2018 vintage grape must from a winery in Buenos Aires, with a particular focus on comparing lactic acid bacteria (LAB) detected through both methods. Six LAB strains were isolated: 4 strains of Lactiplantibacillus plantarum, 1 strain of Enterococcus mundtii, and 1 strain of Enterococcus durans. Initial characterization of Lpb. plantarum strains through the study of their growth kinetics and ethanol resistance suggested them as potential candidates for future malolactic fermentation (MLF) starter formulations. Furthermore, amplicon sequencing analysis using the 16S rRNA gene revealed Proteobacteria, Actinobacteria, and Firmicutes as the most abundant phyla; however, members of the Lactobacillales order, to which LAB belong, were not detected. The results of this study emphasize the need for comprehensive analyses to enhance the detection sensitivity of LAB in grape must and wine samples from these re-emerging wine regions. Studies like this one could be relevant for our country, as they can assist producers in identifying and addressing issues and providing suggestions to improve the fermentation process to achieve higher quality wines and increase their added value.