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Table 2 Product formation by the S. cerevisiae Y294 strains after 192 h of fermentation at 30 °C in 2 × SC−URA broth containing glucose (5 g l−1) and raw corn starch (200 g l−1), as carbon sources, as well as starch hydrolysing activities (U ml−1) when strains were grown in 2 × SC−URA broth for 72 h

From: Construction of industrial Saccharomyces cerevisiae strains for the efficient consolidated bioprocessing of raw starch

S. cerevisiae Y294 strains [TemG_Opt-AmyA] [TemG_Opt-TemA] [TemG_Opt-TemA_Opt] [TemG_Opt-AteA] [TemG_Opt-ApuA] [GlaA-TemA] [AmyA-GlaA]
Substrate (g l−1)
 Raw starch 200 200 200 200 200 200 200
 Glucose equivalent 208.5 208.5 208.5 208.5 208.5 208.5 208.5
Products (g l−1)
 Glucose 2.72 46.30 1.67 1.94 1.21 4.12 5.30
 Glycerol 4.76 6.64 2.40 3.43 2.45 2.26 2.46
 Maltose 1.09 1.03 1.07 1.14 0.95 1.17 1.02
 Acetic acid 1.91 1.66 0.60 0.85 0.61 0.56 0.61
 Ethanol 47.40 62.20 48.71 53.46 43.12 46.56 52.78
 CO a2 45.33 59.50 46.59 51.13 41.25 44.53 50.48
Total 103.21 177.33 101.04 111.95 89.60 99.20 112.65
 Estimated carbon conversion (%) 50 85 49 54 43 48 54
 Ethanol yieldb (% of theoretical yield) 46 60 47 51 41 45 51
 Ethanol productivityc 0.25 0.32 0.25 0.28 0.23 0.24 0.28
2% raw starch assays (U ml−1)
 Total amylase activityd 0.21 0.47 0.16 0.21 0.30 0.13 0.09
 Released glucosee 0.11 0.25 0.06 0.10 0.08 0.03 0.03
 Released glucose equivalentsf 0.16 0.43 0.19 0.35 0.32 0.05 0.05
0.2% soluble starch assays (U ml−1)
 Total amylase activityd 3.30 3.69 2.27 1.90 3.44 2.15 1.84
 Released glucosee 0.69 1.00 0.16 0.32 0.13 0.01 0.02
  1. The assays were performed at 30 °C in citrate buffer at pH 5 with raw and soluble corn starch
  2. aCO2 concentrations were deduced from the ethanol produced
  3. bEthanol yield (% of the theoretical yield) was calculated as the amount of ethanol produced per gram of available glucose (at a specific time point)
  4. cEthanol productivity was calculated based on ethanol concentrations produced per h (g l−1 h−1)
  5. dReducing sugar assay detects all reducing sugars (monosaccharides and oligosaccharides)
  6. eGlucose kit assay detects only glucose
  7. fHPLC detection of glucose and maltose after raw starch assay, released glucose equivalents were converted to activity