## 1 Introduction
cerevisiae_ has fermentable strains and their fermentability would be important in the food industry. Regarding the fermentation by _S. cerevisiae_ using food residues, for instance, the ethanol production by _S. cerevisiae_ was 49.5 g\(\cdot\)L\({}^{-1}\) using 100 g\(\cdot\)L\({}^{-1}\) of instant noodle waste as a nutrient source [14] and 21 g\(\cdot\)L\({}^{-1}\) using 69 g\(\cdot\)L\({}^{-1}\) of reducing sugar derived from potato peel [15], indicating the differences in fermentability due to differences in substrates. Additionally, the cells are possibly caused to switch the metabolic flow depending on the gene transcription levels in the medium containing wheat bran, so that the comprehensively shifted transcription levels as direct cell responses should be as the subject of transcriptome analysis. Transcriptome analysis is a powerful assessment tool to understand how the strains tend to alter their metabolic activities [16], and can reveal how strains tend to switch their metabolic response due to using the food residues. Recently, as a value-added substance-producing strain, mutants of _S. cerevisiae_ have been created to produce those substances instead of ethanol [17], and in particular, genetically modified strains were used to produce various substances such as butanol [18] and amino acids [19]. Therefore, fermentation should be evaluated in the use of the food residues from the viewpoint of not only production of several substances but also the transcription levels relating to that production in broad areas. To date, using food residues, although the evaluation of the fermentative production by _S. cerevisiae_ has been reported many researchers [20; 21; 22], there are few reports of detailed evaluation of the cell responses by transcriptome analysis. The evaluation of the cell responses from the viewpoint of transcriptome analysis could have a significant impact, in the sense that it could lead to controlling intracellular metabolism. In this study, the laboratory yeast _S. cerevisiae_ BY4741 was selected as a targeted strain, and cultured in a wheat bran-fed medium to determine whether wheat bran could be used as a medium component (Table 1). At that time, the cell responses were evaluated by analyses of cell proliferation, growth under nutrient limitation, the production of cells and ethanol, and transcriptomic analysis. This study finally showed the possibility of wheat bran as an alternative nutrient to YNB especially as a templated medium component for _S. cerevisiae_, indicating the reduction in research costs and the expansion of substance producing possibilities. Therefore, the study of using wheat bran as the nutrient for yeast fermentation could demonstrate an industrial impact. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Medium Name** & \multicolumn{2}{c}{**Main Component**} & \multicolumn{2}{c}{**Essential Nutrients**} & \multicolumn{2}{c}{**Corresponding**} \\  & & & & & & & **Figure** \\ \hline WG+HLMU medium & wheat bran & glucose & histidine & leucine & methionine uracil & Figures 1–6 \\ W+HLMU medium & wheat bran & histidine & leucine & methionine uracil & Figure 1 \\ WG+LUM medium & wheat bran & glucose & leucine & methionine uracil & Figure 2 \\ WG+HMU medium & wheat bran & glucose & histidine & methionine uracil & Figure 2 \\ WG+HLU medium & wheat bran & glucose & histidine & leucine & uracil & Figure 2 \\ WG+HLM medium & wheat bran & glucose & histidine & leucine & methionine & Figure 2 \\ \hline YG+HLMU medium (SD medium) & YNB & glucose & histidine & leucine & methionine uracil & Figures 1 and 3–6 \\ Y+HLMU medium & YNB & & histidine & leucine & methionine uracil & Figure 1 \\ \hline G+HLMU medium & & glucose & histidine & leucine & methionine uracil & Figure 1 \\ HLMU medium & & & histidine & leucine & methionine uracil & Figure 1 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: List of medium compositions. Figure 1: Time course profiles of growth of BY4741 in each medium. BY4741 was cultivated to evaluate the growth manners in each medium.