The high cost of cellulose hydrolysis is the bottleneck problem of industrialization of cellulosic ethanol production. Therefore, it is worthwhile to study the hydrolysis and saccharification of substrate under low enzyme usage. This study focused on obtaining high-titer fermentable sugars from fed-batch thick-mash enzymatic hydrolysis by using additives and accessory enzymes. Sugarcane bagasse treated by alkali-catalyzed atmospheric glycerol organosolv (al-AGO) was used as substrate. The optimized amounts of additives were as below: 10 mg/g dry substrate tea saponin, 25 mg/g dry substrate Tween 20, 10 mg/g dry substrate bull serum albumin (BSA), and 0.6 mg/g dry substrate endo-xylanase. In order to reach 350 g/L total solid content during thick-mash enzymatic hydrolysis of al-AGO pretreated lignocellulosic substrate, 190 g/L initial solid content was applied, followed by feeding 60, 50 and 50 g/L substrate at 7, 10 and 13 h, respectively. After 48 h enzymatic hydrolysis with 6 FPU/g dry substrate, the hydrolysis process achieved 220 g/L fermentable sugars, in which, the titers of glucose and xylose were as high as 160.7 g/L and 58.7 g/L, respectively. Therefore, fed-batch strategy is still desirable for thick-mash enzymatic hydrolysis of lignocellulosic substrate, and using reasonable additives and accessory enzymes is evidently conducive for improving the process.
KANEZA PASCAL
,
YANG Linqing
,
SUN Fubao
,
XIAO Zhihong
,
LIU Rukuan
,
SUN Haiyan
. Thick-mash enzymatic hydrolysis of sugarcane bagasse with additivesand accessory enzymes[J]. Food and Fermentation Industries, 2019
, 45(17)
: 1
-6
.
DOI: 10.13995/j.cnki.11-1802/ts.020940
[1] KERSTIN H, MATS G, GUIDO Z. Effects of enzyme feeding strategy on ethanol yield in fed-batch simultaneous saccharification and fermentation of spruce at high dry matter[J]. Biotechnology for Biofuels, 2010, 3(1): 14-14.
[2] LÓPEZ-LINARES J C, ROMERO I, CARA C, et al. Bioethanol production from rapeseed straw at high solids loading with different process configurations[J]. Fuel, 2014, 122(12): 112-118.
[3] ZHANG X, QIN W J, PAICE M G, et al. High consistency enzymatic hydrolysis of hardwood substrates[J]. Bioresource Technology, 2009, 100(23): 5 890-5 897.
[4] GHOSE T K. Measurement of cellulase activities[J]. Pure & Applied Chemistry, 1987, 59(2): 257-268.
[5] YU-AN C, YAN Z, YANLIN Q, et al. Evaluation of the action of Tween 20 non-ionic surfactant during enzymatic hydrolysis of lignocellulose: pretreatment, hydrolysis conditions and lignin structure[J]. Bioresource Technology, 2018, 269: 329-338.
[6] KAAR W E, HOLTZAPPLE M T. Benefits from Tween during enzymic hydrolysis of corn stover[J]. Biotechnology & Bioengineering, 2015, 59(4): 419-427.
[7] TOYOSAWA Y, IKEO M, TANEDA D, et al. Quantitative analysis of adsorption and desorption behavior of individual cellulase components during the hydrolysis of lignocellulosic biomass with the addition of lysozyme[J]. Bioresource Technology, 2017, 234: 150-157.
[8] KÖHNKE T, LUND K, BRELID H, et al. Kraft pulp hornification: A closer look at the preventive effect gained by glucuronoxylan adsorption[J]. Carbohydrate Polymers, 2010, 81(2): 226-233.
[9] MOHAGHEGHI A, TUCKER M, GROHMANN K, et al. High solids simultaneous saccharification and fermentation of pretreated wheat straw to ethanol[J]. Applied Biochemistry & Biotechnology, 1992, 33(2): 67-81.
[10] CASPETA L, CARO-BERMU′DEZ M A, PONCE-NOYOLA T, et al. Enzymatic hydrolysis at high-solids loadings for the conversion of agave bagasse to fuel ethanol[J]. Applied Energy, 2014, 113(1): 277-286.
[11] LIU Y, XU J, ZHANG Y, et al. Optimization of high solids fed-batch saccharification of sugarcane bagasse based on system viscosity changes[J]. Journal of Biotechnology, 2015, 211(66): 5-9.
[12] HODGE D B, M NAZMUL K, SCHELL D J, et al. Model-based fed-batch for high-solids enzymatic cellulose hydrolysis[J]. Applied Biochemistry & Biotechnology, 2009, 152(1): 88.
[13] 王亮, 刘建权,张喆,等. 常压甘油自催化预处理麦草浓醪发酵纤维素乙醇[J]. 生物工程学报, 2015, 31(10): 1 468-1 483.
[14] 洪嘉鹏, 岳春,赵晓琴,等. 常压甘油有机溶剂预处理甘蔗渣的浓醪酶解[J]. 食品与发酵工业, 2017, 43(10): 36-42.