## 3 Results
### Effect of Different C/S Ratios on Biomass, Lipid, and Caroenoid Production
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c c c c c c c c c c} \hline \multirow{2}{*}{**C/N**} & \multirow{2}{*}{**N**} & \multicolumn{3}{c}{**DCW (g/l)**} & \multicolumn{3}{c}{**TL (g/l)**} & \multicolumn{3}{c}{**TP (mg/l)**} & \multicolumn{3}{c}{**DCW-Y (Va)**} & \multicolumn{3}{c}{**TLV (Va)**} & \multicolumn{3}{c}{**TT-Y (Va)**} & \multicolumn{3}{c}{**TT-Y (Va)**} & \multicolumn{3}{c}{**LBP (Ca)**} & \multicolumn{3}{c}{**Car-RF**} & \multicolumn{3}{c}{**Car-SR**} & \multicolumn{3}{c}{**LCSR (g/l-d)**} \\ \cline{3-19}  & & & & & & & & & & & & & & & & & & & & & & & & & & & & & & \\ \hline \multirow{19}{*}{16} & \multirow{2}{*}{PE} & \multirow{2}{*}{PE} & 62.6 \(\pm\) 0.25 & 9.3 \(\pm\) 0.1 & 2.69 \(\pm\) 0.52 & 5.04 \(\pm\) 0.19 & 0.31 \(\pm\) 0.16 & 0.36 \(\pm\) 0.00 & 46.2 & 23.6 & 18.5 & 19.6 & 23.2 & 1.8 & 40.1 & 54.2 & 50.2 & 38.8 & 104 & 16.2 & 0.83 & 0.85 \\  & & & & & & & & & & & & & & & & & & & & & & & & \\ \hline \multirow{19}{*}{16} & \multirow{2}{*}{PE} & 62.6 \(\pm\) 0.56 & 10.43 \(\pm\) 0.09 & 2.47 \(\pm\) 0.51 & 5.2 \(\pm\) 0.18 & 0.44 \(\pm\) 0.07 & 0.64 \(\pm\) 0.08 & 46.2 & 24.9 & 17.5 & 17.9 & 31.3 & 14.5 & 37.4 & 30.0 & 67.0 & 61.6 & 14.8 & 66.3 & 0.82 & 0.92 \\  & & & & & & & & & & & & & & & & & & & & & & \\ \hline \multirow{19}{*}{96} & \multirow{2}{*}{PE} & 62.7 \(\pm\) 0.34 & 9.63 \(\pm\) 0.25 & 2.05 \(\pm\) 0.36 & 4.97 \(\pm\) 0.58 & 0.48 \(\pm\) 0.04 & 0.55 \(\pm\) 0.03 & 47.0 & 24.3 & 14.7 & 16.9 & 37.4 & 15.3 & 33.3 & 64.4 & 58.6 & 77.5 & 85.9 & 0.69 & 0.91 \\  & & & & & & & & & & & & & & & & & & & & & & \\ \hline \multirow{19}{*}{96} & \multirow{2}{*}{PE} & 77.2 \(\pm\) 0.34 & 9.63 \(\pm\) 0.25 & 2.05 \(\pm\) 0.36 & 4.96 \(\pm\) 0.08 & 0.48 \(\pm\) 0.04 & 0.50 & 47.5 & 21.3 & 15.0 & 28.0 & 27.8 & 2.0 & 32.2 & 51.5 & 58.5 & 58.5 & 58.2 & 55.2 & 15.6 & 16.7 & 0.83 & 0.82 \\  & & & & & & & & & & & & & & & & & & & & & & & & \\ \hline \multirow{19}{*}{96} & \multirow{2}{*}{PE} & 7.9 \(\pm\) 0.23 & 11.6 \(\pm\) 0.58 & 2.05 \(\pm\) 0.18 & 5.4 \(\pm\) 0.01 & 0.56 \(\pm\) 0.03 & 47.0 & 47.8 & 20.4 & 17.9 & 39.2 & 14.5 & 40.0 & 64.0 & 64.0 & 70.7 & 67.9 & 188 & 74.5 & 0.82 & 0.99 \\  & & & & & & & & & & & & & & & & & & & & & & & \\ \hline \multirow{19}{*}{70} & \multirow{2}{*}{PE} & 60.8 \(\pm\) 0.18 & 10.4 \(\pm\) 0.3 & 2.30 \(\pm\) 0.51 & 47.5 \(\pm\) 0.37 & 0.48 \(\pm\) 0.06 & 0.53 \(\pm\) 0.02 & 48.5 & 19.6 & 14.1 & 22.9 & 20.1 & 15.9 & 20.1 & 46.9 & 60.0 & 52.3 & 15.0 & 16.2 & 0.78 & 0.81 \\  & & & & & & & & & & & & & & & & & & & & & & & \\ \hline \multirow{19}{*}{71} & \multirow{2}{*}{PE} & 62.8 \(\pm\) 0.14 & 12.2 \(\pm\) 0.2 & 2.20 \(\pm\) 0.17 & 4.98 \(\pm\) 0.14 & 0.57 \(\pm\) 0.04 & 0.88 \(\pm\) 0.05 & 50.4 & 24.7 & 13.3 & 17.5 & 33.7 & 17.9 & 26.7 & 40.8 & 64.7 & 69.0 & 52.3 & 16.2 & 0.88 & 0.92 \\  & & & & & & & & & & & & & & & & & & & & & & & \\ \hline \multirow{19}{*}{72} & \multirow{19}{*}{PE} & 62.6 \(\pm\) 0.56 & 10.43 \(\pm\) 0.09 & 2.47 \(\pm\) 0.15 & 2.5 \(\pm\) 0.18 & 0.44 \(\pm\) 0.07 & 0.64 \(\pm\) 0.08 & 46.2 & 23.6 & 18.5 & 19.6 & 21.2 & 38.6 & 15.2 & 22.5 & 34.9 & 79.5 & 79.4 & 192 & 102 & 0.54 & 0.75 In contrast to lipids, TP production increased with decreasing C/S ratios to be 0.875 mg/L at C/S 98 compared with 0.528 mg/L at C/S 254, which represents around a 1.7-fold increase. Also, the total pigment of C/S ratio 254 was statistically significant with TP of C/S 98 and highly significant with C/S 123 after three days, and was statistically significant with C/S 166, C/S 123, and C/S 98 after six days. Additionally, Car-RP kept increasing with the gradual decreasing of the C/S ratio to be almost the same--85.9 ug/g and 86 ug/g at C/S ratio 123 and C/S ratio 98, respectively--compared with 70.7 ug/g at C/S 254 after three days, which represented around a 1.2-fold increase. The reports on the effect of the C/S ratio on carotenoid production by yeast are still few in number. An earlier study reported the effect of MgSO\({}_{4}\) on carotenoid production by mutant 32 of _R.