Comparison of Yeast Cell Viability Assessment Techniques Post-Fermentation in Agave sisalana Juice

Abstract

This study compares different methods for assessing yeast cell viability in Agave sisalana juice fermentation, focusing on first-generation ethanol production. Methylene blue staining, CFU counting, and resazurin assays were employed to evaluate cell viability. The results indicated a significant decrease in CFU of yeasts cultivated in Agave juice compared to the standard YPD medium. Methylene blue staining did not show a clear difference in viability between the two media. However, resazurin assays revealed a 90% reduction in viability at the 10-3 dilution. The study highlights the interference of Agave juice particles, color, and other compounds in the traditional viability assays. Despite these challenges, new methods demonstrated potential for rapid and accurate determination of yeast viability, offering a promising approach for optimizing biotechnological processes in Agave juice fermentation. Further research is needed to develop a customized, efficient, and industrially applicable protocol for cell viability assessment in Agave juice.