温度对麦秸混合物料厌氧干发酵中糖类水解酶活性的影响  

Effect of temperature on carbohydrate hydrolase activity during dry anaerobic fermentation of mixed wheat straw

作　　者：牛俊玲[1] 梁丽珍[1] 刘蕾[1] 张全国[2] 

机构地区：[1]郑州航空工业管理学院资源与环境研究所,郑州450015 [2]河南农业大学机电工程学院,郑州450002

出　　处：《中国生态农业学报》2013年第10期1271-1276,共6页Chinese Journal of Eco-Agriculture

基　　金：国家科技支撑计划项目(2008BADC4B02);河南省高校青年骨干教师计划项目(2009GGJS-0990)资助

摘　　要：水解酶活性直接影响到秸秆厌氧干发酵的沼气产量。本文以麦秸为主要原料,配制干物质含量(TS)35%的混合发酵物料,设置20℃、25℃、30℃、35℃、40℃5种不同温度条件,发酵周期为35 d,测定发酵过程中料液的纤维素酶、木聚糖酶、淀粉酶和蔗糖酶的活性变化。结果表明,沼气产气高峰在35℃左右,20～40℃时,随着温度的升高,发酵后料液的料液干物质含量(TS)、可挥发固体含量(VS)、C/N均明显下降,发酵产沼气后,各处理发酵液pH都降到7.0以下,其中40℃的pH降低幅度最大。纤维素酶活性在发酵初期较低,峰值出现也较晚,温度升高明显有利于提高纤维素酶活性。木聚糖酶的起始活性较高,整个发酵过程中呈先升高后降低并渐趋于平缓的变化趋势,20～25℃处理的木聚糖酶活性在整个发酵过程中没有明显峰值。淀粉酶的起始活性较低,但随后迅速升高,30～40℃处理在10 d左右达到峰值后开始下降,此后酶活力的变化幅度较前期平稳。蔗糖酶的起始酶活力较低,随后升高迅速,温度在30℃以上时酶活性增加更快,35℃时15 d达到峰值后迅速下降,下降速度明显大于30℃和40℃处理。由此可见,温度对秸秆厌氧干发酵过程中不同水解酶活性的影响还是有所差异的。The production of biogas by anaerobic dry fermentation of straw could decrease environmental pollution from burning straw and at the same time produce abundant biogas residue that can be used as eco-organic fertilizer. However, the application of anaerobic dry fermentation of straw has been limited by the long processing cycle and slow rate of gas production. Hydrolysis has been identified as the factor slowing down straw fermentation, and carbohydrate hydrolase is a key element of hydrolysis. Biogas yield from the dry anaerobic fermentation of wheat straw was directly affected by hydrolase activity. Thus using wheat straw as the main component, carbohydrate hydrolase activities was studied during anaerobic dry fermentation under different temperature conditions in this study. The purpose of this study was to lay theoretical basis for increasing biogas production rate and shortening the residence time of straw fermentation through enzyme engineering. In the experiment, the fermentation materials were the mixture of wheat straw, inoculums and water with the proportion of 1 ： 7 ： 7. Total substance （TS） of the mixed materials was 35%. The experiment was carried out in wild-mouth bottle （as the fermentation container） and under different temperatures （20℃, 25 ℃, 30℃, 35℃ and 40℃） and with fermentation period of 35 days. The activities of cellulase, xylanase, amylase and sucrase were measured during the dry fermentation process of wheat straw mixture. The results showed that biogas production peaked at about 35℃. For the 20-40 ℃ temperature range, TS, volatilizable substance （VS） and carbon/nitrogen （C/N） ratio for the fermenting mixture decreased apparently with increasing temperature. With the end of fermentation, the pH of the fermenting materials in all the treatmentsdeclined under 7.0. The lowest pH was under the 40℃ condition. Cellulase activity was low during the initial period of fermentation while biogas production peaked later in the fermentation process. The rise in

关 键 词：麦秸 厌氧干发酵 糖类水解酶 温度 

分 类 号：S216.4[农业科学—农业机械化工程]