Egyptian sugarcane bagasse

Cellulose 41.3% Hemicellulose 27.4% Lignin 12.1%

Chipped, ground bagasse autoclaved at 121˚C for 20 min

Separate hydrolysis and fermentation: (i) Biological hydrolysis using Trichoderma viride and fermentation using Candida tropicalis; (ii) Biological hydrolysis using Aspergillus terreus and fermentation using S. cerevisiae Fermentation at 30˚C, 48 h and inoculum 10% v/v

(i) 249 kg of ethanol tonne⁻¹ bagasse; (ii) 204 kg of ethanol tonne⁻¹ bagasse

[53]

Sugar cane bagasse

Cellulose 42% Hemicellulose 25% Lignin 20% [54]

Dilute sulphuric acid (1% v/v) treatment at 121˚C for 45 min with a solid to liquid ratio of 1:2 followed by NaOH (4% w/v) treatment at 121˚C for 30 min with a solid to liquid ratio of 1:20

Simultaneous Saccharification using enzyme prepared using Pencillium funiculosum ATCC 11797 and pretreated sugarcane bagasse substrate followed by fermentation using S. cerevisiae at 37˚C, pH 5, 144 h and inoculum 15 g∙L⁻¹

Ethanol 100 g∙L⁻¹, 121.2 L of ethanol tonne⁻¹ of sugarcane bagasse

[55]

Sugar beet pulp

4717360 tonnes annum⁻¹ from US, Europe and Asia [56] and 17 million tonnes sugar beet annum⁻¹

Total carbohydrate 80%:

Rhamnose 2.4% Arabinose 23.0% Galactose 6.2% Glucose 25.9% Mannose 1.0% Xylose 1.7% Galacturonic acid 14.4%

Steam pretreatment at 152˚C - 175.5˚C and 4 - 8 bar(g) pressure

Enzymatic hydrolysis using commercially available cellulase at 50˚C for 24 h followed by fermentation using S. cerevisiae at 30˚C for 24 h and other conditions not available

0.5 g ethanol per g of glucose from sugar beet pulp

[57]

Sweet sorghum bagasse (SSB) 36.0 - 45.4 tons/ha [58]

Carbohydrates 58.3% Lignin 18.6% Ash 1.9% Extractives 21.2%

Steam pretreatment of 2.5% SO₂ impregnated bagasse at 200˚C for 7.5 min

Enzymatic hydrolysis using commercial cellulase and β-glucosidase at 50˚C for 72 h followed by fermentation using S. cerevisiae at 30˚C, pH 6, 48 h and inoculum 3 - 5 g∙L⁻¹

15.3 g ethanol 100 g⁻¹ SSB, 72.7% conversion of hexose sugars to ethanol

[59]

Sweet sorghum bagasse (SSB)

Cellulose 34% - 45% Hemicellulose 25% - 27%

Lignin 18% - 21 % [54]

SSB in dilute NaOH solution (2% w/v) autoclaving at 121˚C for 60 min and H₂O₂ immersing

Enzymatic hydrolysis at 50˚C using Celluclast supplemented with β-glucosidase followed by fermentation using Active dry yeast at 30˚C and inoculum at 1:10 volume ratio of yeast medium to fermentation broth

Total sugar yield of 90.9 g sugar 100 g⁻¹ dry SSB, Ethanol 6.1 g∙L⁻¹

[60]

Sweet sorghum bagasse (SSB)

NaOH pretreatment

Enzymatic hydrolysis using commercial cellulase and xylanase from Novozyme followed by fermentation using Zymomonas mobilisat 32˚C, pH 6, 30 h and inoculum Z. mobilis culture at 10% v/v

61.8% of the theoretical ethanol yield

[61]

Sweet sorghum stover

Dilute sulphuric acid (0.37% v/v) treatment in a high pressure reactor at 150˚C for 15 min

Enzymatic hydrolysis using commercial cellulase (Zytex) at 50˚C for 48 h followed by fermentation using S. cerevisiae at 30˚C, 48 h and inoculum 0.27 g∙L⁻¹

91.9 g ethanol∙kg⁻¹ native sorghum

[62]

Rice straw 34.3 million tonnes annum⁻¹ from Thailand

Cellulose 32% - 47 % Hemicellulose 13% - 27 %

Aqueous ammonia (27% w/w) treatment at 1:12 solid: liquid ratio at room temperature (25˚C ± 3˚C) for 14 days followed by washing

SSF using cellulase (Cellic Ctec2) and xylanase (Cellic Htec2) and S. cerevisiae and Candida tropicalis at 37˚C for 72 h and inoculum 1.2 g yeast in 10 mL YP medium

25.1 g∙L⁻¹, Y_p/s 0.4 g∙g⁻¹

[63]