Fig. 1
a Stress tolerance ability of dung beetle-associated yeasts. Ninety-seven dung beetle-associated yeasts were spot tested on YPD agar with varying formic acid (10 mM, 15 mM, and 20 mM) and acetic acid concentrations (40 mM, 45 mM, and 50 mM) to test for formic acid tolerance and acetic acid tolerance, respectively. The incubation temperature was set at 30 °C. The yeasts were also tested for thermotolerance on YPD agar and incubated at various high temperatures (40 °C, 42 °C, and 44 °C). The gradient shows the absorbance of the inoculum from left to right: 0.2, 0.1, and 0.05. The control S. cerevisiae (Ethanol redTM) was spotted on every plate. See also Additional file 1. b Stress tolerance ability of dung beetle-associated yeasts. Ninety-seven dung beetle-associated yeasts were spot tested on YPD agar with varying formic acid (10 mM, 15 mM, and 20 mM) and acetic acid concentrations (40 mM, 45 mM, and 50 mM) to test for formic acid tolerance and acetic acid tolerance, respectively. The incubation temperature was set at 30 °C. The yeasts were also tested for thermotolerance on YPD agar and incubated at various high temperatures (40 °C, 42 °C, and 44 °C). The gradient shows the absorbance of the inoculum from left to right: 0.2, 0.1, and 0.05. The control S. cerevisiae (Ethanol redTM) was spotted on every plate. See also Additional file 1. c Stress tolerance ability of dung beetle-associated yeasts. Ninety-seven dung beetle-associated yeasts were spot tested on YPD agar with varying formic acid (10 mM, 15 mM, and 20 mM) and acetic acid concentrations (40 mM, 45 mM, and 50 mM) to test for formic acid tolerance and acetic acid tolerance, respectively. The incubation temperature was set at 30 °C. The yeasts were also tested for thermotolerance on YPD agar and incubated at various high temperatures (40 °C, 42 °C, and 44 °C). The gradient shows the absorbance of the inoculum from left to right: 0.2, 0.1, and 0.05. The control S. cerevisiae (Ethanol redTM) was spotted on every plate. See also Additional file 1. d Stress tolerance ability of dung beetle-associated yeasts. Ninety-seven dung beetle-associated yeasts were spot tested on YPD agar with different hydrogen peroxide concentrations (H2O2) (3 mM, 5 mM, and 7 mM) for the oxidative stress tolerance test; different sodium chloride (NaCl) concentrations (1 M and 1.5 M) for the osmotolerance test and different ethanol concentrations (5%, 7%, and 9%) for the ethanol tolerance test. The incubation temperature was set at 30 °C. The gradient shows the absorbance of the inoculum from left to right: 0.2, 0.1, and 0.05. The control S. cerevisiae (Ethanol redTM) was spotted on every plate. See also Additional file 1. e Stress tolerance ability of dung beetle-associated yeasts. Ninety-seven dung beetle-associated yeasts were spot tested on YPD agar with different hydrogen peroxide concentrations (H2O2) (3 mM, 5 mM, and 7 mM) for the oxidative stress tolerance test; different sodium chloride (NaCl) concentrations (1 M and 1.5 M) for the osmotolerance test and different ethanol concentrations (5%, 7%, and 9%) for the ethanol tolerance test. The incubation temperature was set at 30 °C. The gradient shows the absorbance of the inoculum from left to right: 0.2, 0.1, and 0.05. The control S. cerevisiae (Ethanol redTM) was spotted on every plate. See also Additional file 1. f Stress tolerance ability of dung beetle-associated yeasts. Ninety-seven dung beetle-associated yeasts were spot tested on YPD agar with different hydrogen peroxide concentrations (H2O2) (3 mM, 5 mM, and 7 mM) for the oxidative stress tolerance test; different sodium chloride (NaCl) concentrations (1 M and 1.5 M) for the osmotolerance test and different ethanol concentrations (5%, 7%, and 9%) for the ethanol tolerance test. The incubation temperature was set at 30 °C. The gradient shows the absorbance of the inoculum from left to right: 0.2, 0.1, and 0.05. The control S. cerevisiae (Ethanol redTM) was spotted on every plate. See also Additional file 1