碱性双氧水预处理对苹果渣化学组分和酶解得率的影响

doi:10.3864/j.issn.0578-1752.2016.08.013

摘要/Abstract

摘要： 【目的】利用浓度为4.5%、pH 11.5的双氧水（alkaline hydrogen peroxide，AHP）预处理苹果渣，研究其对苹果渣化学组分、木质素的去除率和纤维素酶的酶解得率的影响。【方法】以木质素的去除率为指标，优化AHP预处理的温度和时间，经过过滤收集固体组分、干燥后，制得预处理后的苹果渣。根据AHP预处理前苹果渣中纤维素、半纤维素的含量、木质素的含量以及酶解总糖含量，分析AHP在最优预处理温度下，不同预处理时间对苹果渣纤维素、半纤维素的含量及回收率，木质素的含量及去除率、酶解糖得率的影响。通过扫描电镜（scanning electron microscope，SEM）、热重分析法（thermogravimetry/differential thermogravimetry，TG/DTG）和傅里叶变换红外光谱（fourier transform infrared，FTIR）表征AHP处理前后的苹果渣物理结构、化学组分的变化。【结果】预处理的时间和温度对苹果渣木质素的去除率有显著的影响。综合考虑各方面的因素，尤其是经济效益，当预处理时间为2 h、温度为50℃时，木质素的去除率最优，可达到56.68%。在最优的预处理温度下，分析不同预处理时间后苹果渣的组分变化及酶解得率。当预处理时间为2 h时，纤维素、半纤维素回收率可达99.86%，非常接近未处理果渣中的含量；苹果渣的酶解糖得率可达到0.54 g·g^-1，是未处理果渣酶解得率的2倍。扫描电镜（SEM）图像对比说明AHP预处理使得果渣的物理结构变得多孔而疏松，纤维束变得宽松而粗糙，内表面积无限增大。热重分析法（TG/DTG）表明AHP预处理明显提高了纤维素组成单体的纯度，减少了预处理后果渣中木质素及残留物的含量。红外光谱（FTIR）研究揭示AHP预处理可以破坏木质素的化学结构，组成木质素的愈创木基、紫丁香基和对羟苯基等基本物质的结构被AHP破坏，从而使得AHP处理后果渣中木质素的含量明显降低。【结论】双氧水是一种有效的苹果渣预处理剂，其预处理效果与预处理的温度和时间有密切联系。

关键词: 苹果渣, 碱性双氧水, 酶水解, 木质素, 特征结构分析

Abstract: 【Objective】 The aim of this study was to research the impact of a 4.5% alkaline hydrogen peroxide (AHP) pretreatment at pH 11.5 on the chemical composition of apple pomace, the lignin removal rate, and the enzymatic hydrolyzability of cellulase. 【Method】 The temperature and time of pretreatment were optimized in accordance with the index of the lignin removal rate in this study. After filtering to collect solid components and drying, the AHP pretreated apple pomace was obtained. According to the content of cellulose and hemicellulose, the content of lignin, and total sugar content of enzymatic hydrolysis of apple pomace before AHP, the effects of different pretreated time on the content and recovery of cellulose and hemicellulose, the content and removal rate of lignin, and the enzymatic hydrolyzability were analyzed under the optimal pretreatment temperature. Utilizing a scanning electron microscope (SEM), thermogravimetry/differential thermogravimetry (TG/DTG), and fourier transform infrared (FTIR) characterized the physical and chemical composition change of apple pomace before and after AHP. 【Result】 The temperature and time of pretreatment had significant effects on the lignin removal rate. Considering various factors, especially the economic benefits, when the time was 2 hours and the temperature was 50℃, the lignin removal rate was optimal with 56.68%. The composition variation and enzymatic hydrolyzability of apple pomace after different pretreated times was analyzed under optimal pretreated temperature. When pretreated time was 2 hours, the recovery of cellulose and hemicellulose was 99.86%, which was very close to the content of untreated apple pomace; the enzymatic hydrolyzability was 0.54 g·g^-1, which was 200% of untreated apple pomace. The SEM images showed that the physical structure was multi-hole and loose, the fiber bundle became loose and rough, and the internal surface area was indefinitely increased after apple pomace treated with AHP. TG/DTG demonstrated that AHP could apparently increase the purity of cellulose monomer and reduce the content of lignin and residue. The FTIR study revealed that AHP could substantially disrupt the chemical structure of lignin, and the structure of guaiacyl, syringyl, and p-hydroxylphengl of lignin was destroyed. Thus, the lignin content of apple pomace was reduced after AHP. 【Conclusion】 This paper illustrated that AHP was an efficient pretreatment agent of apple pomace, and that the effect of pretreatment was closely associated with temperature and time.

Key words: apple pomace, alkaline hydrogen peroxide, enzymatic hydrolyzability, lignin, characteristic structure analysis

尤毅娜，邓红，孟永宏，房杰，郭玉蓉，张英. 碱性双氧水预处理对苹果渣化学组分和酶解得率的影响[J]. 中国农业科学, 2016, 49(8): 1559-1566.

YOU Yi-na, DENG Hong, MENG Yong-hong, FANG Jie, GUO Yu-rong, ZHANG Ying . The Impact of Alkaline Hydrogen Peroxide Pretreatment on the Chemical Composition and Enzymatic Hydrolyzability of Apple Pomace[J]. Scientia Agricultura Sinica, 2016, 49(8): 1559-1566.

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参考文献

[1] 于滨, 吴茂玉, 朱凤涛, 和法涛. 苹果渣综合利用研究进展. 中国果蔬, 2012(12): 31-34.

Yu B,Wu M Y, Zhu F T, He F T. Comprehensive utilization of apple pomace: A review. China Fruit and Vegetable, 2012(12): 31-34. (in Chinese)

[2] Pauly M, Keegstra K. Plant cell wall polymers as precursors for biofuels. Current Opinion in Plant Biology, 2010, 13(3): 304-311.

[3] Da Costa Correia J A, Júnior J E M, Gonçalves L R B, Rocha M V P. Alkaline hydrogen peroxide pretreatment of cashew apple bagasse for ethanol production: study of parameters. Bioresource Technology, 2013, 139: 249-256.

[4] Lynd L R, Laser M S, Bransby D, Dale B E, Davison B, Hamilton R, Himmel M, Keller M, McMillan J D, Sheehan J, Wyman C E. How biotech can transform biofuels. Nature Biotechnology, 2008, 26(2): 169-172.

[5] Chundawat S P S, Donohoe B S, da Costa Sousa L, Elder T, Agarwal U P, Lu F, Ralph J, Himmel M E, Balan V, Dale B E. Multi-scale visualization and characterization of lignocellulosic plant cell wall deconstruction during thermochemical pretreatment. Energy & Environmental Science, 2011, 4(3): 973-984.

[6] Gould J M. Studies on the mechanism of alkaline peroxide delignification of agricultural residues. Biotechnology and Bioengineering, 1985, 27(3): 225-231.

[7] Rabelo S C, Maciel Filho R, Costa A C. A comparison between lime and alkaline hydrogen peroxide pretreatments of sugarcane bagasse for ethanol production. Applied Biochemistry and Biotechnology, 2008, 148: 45-58.

[8] Rabelo S C, Maciel Filho R, Costa A C. Lime pretreatment and fermentation of enzymatically hydrolyzed sugarcane bagasse. Applied Biochemistry and Biotechnology, 2013, 169(5): 1696-1712.

[9] Patel M M, Bhatt R M. Optimisation of the alkaline peroxide pretreatment for the delignification of rice straw and its applications. Journal of Chemical Technology and Biotechnology, 1992, 53(3): 253-263.

[10] Banerjee G, Car S, Scott-Craig J S, Hodge D B, Walton J D. Alkaline peroxide pretreatment of corn stover: effects of biomass, peroxide, and enzyme loading and composition on yields of glucose and xylose. Biotechnol Biofuels, 2011, 4(1): 1-16.

[11] Balat M. Production of bioethanol from lignocellulosic materials via the biochemical pathway: A review. Energy Conversion and Management, 2011, 52(2): 858-875.

[12] Cao W, Sun C, Liu R, Yin R, Wu X. Comparison of the effects of five pretreatment methods on enhancing the enzymatic digestibility and ethanol production from sweet sorghum bagasse. Bioresource Technology, 2012, 111: 215-221.

[13] Alvarez-Vasco C, Zhang X. Alkaline hydrogen peroxide pretreatment of softwood: Hemicellulose degradation pathways. Bioresource Technology, 2013, 150: 321-327.

[14] Da Costa J A, Marques J J E, Gonçalves L R B, Rocha M V P. Enhanced enzymatic hydrolysis and ethanol production from cashew apple bagasse pretreated with alkaline hydrogen peroxide. Bioresource Technology, 2015, 179: 249-259.

[15] Shao Q, Cheng C, Ong R G, Zhu L, Zhao C. Hydrogen peroxide presoaking of bamboo prior to AFEX pretreatment and impact on enzymatic conversion to fermentable sugars. Bioresource Technology, 2013, 142: 26-31.

[16] Diaz A, Le Toullec J, Blandino A, De Ory I, Caro I. Pretreatment of rice hulls with alkaline peroxide to enhance enzyme hydrolysis for ethanol production. Chemical Engineering Transactions, 2013, 32: 949-954.

[17] Michalska K, Ledakowicz S. Alkali pre-treatment of Sorghum Moench for biogas production. Chemical Papers, 2013, 67(9): 1130-1137.

[18] Ayeni A O, Hymore F K, Mudliar S N, Deshmukh S C, Satpute D B, Omoleye J A, Pandey R A. Hydrogen peroxide and lime based oxidative pretreatment of wood waste to enhance enzymatic hydrolysis for a biorefinery: Process parameters optimization using response surface methodology. Fuel, 2013, 106: 187-194.

[19] Miller G L. Use of dinitrosalicylic acid reagent for determination of reducing sugar. Analytical Chemistry, 1959, 31(3): 426-428.

[20] Harrison M D, Zhang Z, Shand K, O’Hara I M, Doherty W O, Dale J L. Effect of pretreatment on saccharification of sugarcane bagasse by complex and simple enzyme mixtures. Bioresource Technology, 2013, 148: 105-113.

[21] Zhang Z, O’Hara I M, Doherty W O S. Pretreatment of sugarcane bagasse by acidified aqueous polyol solutions. Cellulose, 2013, 20(6): 3179-3190.

[22] Zhang J, Feng L, Wang D, Zhang R, Liu G, Cheng G. Thermogravimetric analysis of lignocellulosic biomass with ionic liquid pretreatment. Bioresource Technology, 2014, 153: 379-382.

[23] Singh S, Varanasi P, Singh P, Adams P D, Auer M, Simmons B A. Understanding the impact of ionic liquid pretreatment on cellulose and lignin via thermochemical analysis. Biomass and Bioenergy, 2013, 54: 276-283.

[24] Gao A H, Bule M V, Laskar D D, Chen S. Structural and thermal characterization of wheat straw pretreated with aqueous ammonia soaking. Journal of Agricultural and Food Chemistry, 2012, 60(35): 8632-8639.

[25] Pandey K K, Pitman A J. FTIR studies of the changes in wood chemistry following decay by brown-rot and white-rot fungi. International Biodeterioration & Biodegradation, 2003, 52(3): 151-160.

[26] Yu G, Afzal W, Yang F, Padmanabhan S, Liu Z, Xie H, Shafy M A, Bell A T, Prausnitz J M. Pretreatment of Miscanthus×giganteus using aqueous ammonia with hydrogen peroxide to increase enzymatic hydrolysis to sugars. Journal of Chemical Technology and Biotechnology, 2014, 89(5): 698-706.

[27] Singh D, Zeng J, Laskar D D, Deobald L, Hiscox W C, Chen S. Investigation of wheat straw biodegradation by phanerochaete chrysosporium. Biomass and Bioenergy, 2011, 35(3): 1030-1040.

[28] Lawther J M, Sun R, Banks W B. Fractional characterization of wheat straw lignin components by alkaline nitrobenzene oxidation and FT-IR spectroscopy. Journal of Agricultural and Food Chemistry, 1996, 44(5): 1241-1247.

[29] Singh J, Suhag M, Dhaka A. Augmented digestion of lignocellulose by steam explosion, acid and alkaline pretreatment methods: A review. Carbohydrate Polymers, 2015, 117: 624-631.

[30] Prasad S, Singh A, Jain N, Joshi H C. Ethanol production from sweet sorghum syrup for utilization as automotive fuel in India. Energy & Fuels, 2007, 21(4): 2415-2420.

[31] Kumar A, Singh L K, Ghosh S. Bioconversion of lignocellulosic fraction of water-hyacinth (Eichhornia crassipes) hemicellulose acid hydrolysate to ethanol by Pichia stipitis. Bioresource Technology, 2009, 100(13): 3293-3297.

[32] Rabelo S C, Filho R M, Costa A C. A comparison between lime and alkaline hydrogen peroxide pretreatments of sugarcane bagasse for ethanol production. Applied Biochemistry and Biotechnology, 2008, 148: 563-576.

[33] 耿乙文, 哈益明, 靳婧, 李庆鹏. 过氧化氢改性苹果渣膳食纤维的研究. 中国农业科学, 2015, 48(19): 3979-3988.

Geng Y W, Ha Y M, Jin J, Li Q P. Apple pomace dietary fibre modification by hydrogen peroxide. Scientia Agricultura Sinica, 2015, 48(19): 3979-3988. (in Chinese)

[34] Sun C, Liu R, Cao W, Yin R, Mei Y, Zhang L. Impacts of alkaline hydrogen peroxide pretreatment on chemical composition and biochemical methane potential of agricultural crop stalks. Energy & Fuels, 2015, 29(8): 4966-4975.

[35] Silverstein R A, Chen Y, Sharma-Shivappa R R, Boyette M D, Osborne J. A comparison of chemical pretreatment methods for improving saccharification of cotton stalks. Bioresource Technology, 2007, 98(16): 3000-3011.

[36] Agbor V B, Cicek N, Sparling R, Berlin A, Levin D B. Biomass pretreatment: fundamentals toward application. Biotechnology Advances, 2011, 29(6): 675-685.

[37] Pan X, Xie D, Yu R W, Lam D, Saddler J N. Pretreatment of lodgepole pine killed by mountain pine beetle using the ethanol organosolv process: Fractionation and process optimization. Industrial & Engineering Chemistry Research, 2007, 46(8): 2609-2617.