The Potential of Cellulosic Ethanol Production from Grasses in Thailand
Table 2
Total cellulose and hemicellulose of grasses before pretreatment and hydrolysis and total reducing sugar released after hydrolysis.
Grasses
Total cellulose and hemicellulose before pretreatment and hydrolysis
Total reducing sugar after hydrolysis
% conversion
Total reducing sugar after hydrolysis (ton/ha/year)
Theoretical ethanol yield (L/ha/year)*
(mg/g substrate)
mg/g substrate
g/L
Napier
693.76 ± 26.67
528.58 ± 11.76
4.14 ± 0.34
76.19 ± 1.70
4.05
2,621.06
Dwarf napier
698.37 ± 10.78
558.61 ± 15.58
4.13 ± 0.34
79.99 ± 2.23
9.78
6,331.31
King napier
631.40 ± 4.91
516.63 ± 8.82
4.04 ± 0.32
81.82 ± 1.40
3.96
2,561.81
Bana
690.54 ± 36.65
556.27 ± 24.94
4.36 ± 0.46
80.56 ± 3.62
4.26
2,758.31
Purple guinea
646.60 ± 17.78
553.20 ± 22.22
4.34 ± 0.54
85.56 ± 3.44
10.37
6,717.88
Ruzi
676.53 ± 17.24
469.13 ± 19.09
3.97 ± 0.61
69.34 ± 2.82
6.60
4,272.69
Pangola
685.30 ± 19.62
521.03 ± 5.78
4.09 ± 0.39
76.03 ± 0.84
19.54
12,654.31
Atratum
674.70 ± 11.09
505.93 ± 27.58
4.01 ± 0.53
74.99 ± 4.09
9.49
6,143.81
Kamphaeng Phet 2
745.60 ± 7.74
586.55 ± 22.59
4.60 ± 0.56
78.67 ± 3.03
3.54
2,295.91
Songkhla 3
697.13 ± 29.98
510.94 ± 37.41
3.98 ± 0.20
73.29 ± 5.37
2.97
1,921.38
Surat Thani
730.90 ± 4.13
563.81 ± 18.02
4.42 ± 0.50
77.14 ± 2.47
3.12
2,017.50
Sri Lanka
758.70 ± 25.11
619.31 ± 6.38
4.85 ± 0.42
81.63 ± 0.84
3.95
2,557.00
Roi Et
766.50 ± 9.15
516.95 ± 16.35
3.81 ± 0.33
67.44 ± 2.13
1.83
1,184.36
Loei
768.53 ± 6.05
550.89 ± 22.62
4.31 ± 0.27
71.68 ± 2.94
2.71
1,757.17
Nakhon Sawan
722.70 ± 4.20
532.25 ± 17.80
4.37 ± 0.58
73.64 ± 2.46
2.25
1,456.41
Prachuap Khiri Khan
744.05 ± 14.42
573.62 ± 4.92
4.31 ± 0.19
77.09 ± 0.66
4.85
3,139.24
Ratchaburi
777.20 ± 4.50
616.34 ± 18.36
4.54 ± 0.25
79.30 ± 2.36
4.68
3,033.76
Kamphaeng Phet 1
746.17 ± 7.01
578.10 ± 16.80
4.52 ± 0.28
77.48 ± 2.25
3.73
2,414.94
α-cellulose + xylan
1,000.00 ± 0.00
753.94 ± 6.89
8.76 ± 0.06
75.39 ± 0.69
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Grasses (0.6 g) were pretreated with alkaline peroxide (7.5% (v/v) H2O2; pH 11.5; 35°C, 24 h) followed by enzymatic hydrolysis at 50°C for 72 h. Positive control was 0.3 g of α-cellulose mixed with 0.3 g of xylan.
*Theoretical ethanol yield (L/ha/year) was calculated from total reducing sugars after enzymatic hydrolysis, assuming that the theoretical ethanol yield for fermenting is 0.511 g per g of hexose or pentose.
