Volatile Analysis of Sucrose-Grown Saccharomyces cerevisiae

Fruit flies are naturally attracted to fermenting yeast because yeasts are necessary for Drosophila courtship and egg production and serve as a food source for larval development. Therefore, fermentation-based traps have been used to lure fruit fly pests. Such traps contain sucrose solution as the sole source of carbohydrates for yeast fermentation. However, the volatile organic compounds (VOCs) produced during sucrose fermentation by yeast have yet to be determined. We used SPME-GC/MS analysis and identified VOCs produced by Saccharomyces cerevisiae grown on 50 mM sucrose for 1 h, 1 day, and 4 days. A total of 101 VOCs were identified, representing acids, alcohols, aldehydes, and ketones. The abundance of VOCs varied, with five major VOCs (2-methylbutanol, 3-methylbutanol, ethanol, 2-phenethyl alcohol, and ethyl octanoate) representing 80% of all volatile abundance. The abundance of some VOCs increases over time, whereas others decrease or do not change over time. Future studies will determine specific VOCs that contribute to attracting fruit flies to sucrose-fermenting yeast.