【摘要】 采用体外培养技术,研究不同添加水平的多山梨醇酯20对棉花秸秆体外发酵的影响。结果表明:多山梨醇酯20能显著提高棉花秸秆体外发酵24 h的累积产气量和发酵速度。与对照组相比,0.1%、0.2%、0.4%和0.8%的多山梨醇酯20使24 h累积产气量分别提高27.95%(P<0.01)、32.30%(P<0.01)、43.48%(P<0.01)和19.88%(P<0.01)。多山梨醇酯20使棉花秸秆中的干物质、有机物、纤维素和半纤维素24h降解率提高,其中0.2%组的干物质、有机物和半纤维素的24 h降解率为各组最高,分别比对照组提高12.71%(P<0.05)、11.81%(P>0.05)和115.96%(P<0.01);纤维素的24h降解率以0.4%最高,较0%提高33.67%(P<0.01)。添加多山梨醇酯20后,使pH和还原糖显著下降。除0.2%组外,总挥发性脂肪酸显著高于对照组。羧甲基纤维素酶(CMCase)活性有增加的趋势,0.8%组的CMCase活性较0%组高114.05%(P<0.01)。低浓度多山梨醇酯20有提高微生物(MCP)的趋势,但随着多山梨醇酯20添加浓度的增加,MCP逐渐下降,培养上清中的氨态氮浓度呈现线性增加。在体外厌氧培养条件下,多山梨醇酯20明显促进棉花秸秆在混合绵羊瘤胃液中的降解。更多还原

【Abstract】 The surfactant polysorbate 20 was evaluated for its effects on the in vitro fermentation of cotton-straw by mixed sheep ruminal microorganisms.The results showed that polysorbate 20 raised 24h accumulative gas production and fermentation rate.Compared with the control group,the 24h cumulative gas production of 0.1%,0.2%,0.4% and 0.8% group increased by 27.95%(P<0.01)、32.30%(P<0.01)、43.48%(P<0.01) and 19.88%(P<0.01)respectively.The degradability of DM,OM and hemicellulose in 0.2% group and cellulose in 0.4% group were improved by 12.71%(P<0.05),11.81%(P>0.05),115.96%(P<0.01) and 33.67%(P<0.01)respectively.At the end of 24h anaerobic culture,the pH and reducing sugar decreased significantly.The TVFA increased dramatically in all treated groups except for the 0.2% group.After the addition of polysorbate 20,the CMCase activity of the 0.8% group increased by 114.05%(P<0.01) compared with that of the control group.The MCP tended to increase in groups of lower concentration,while decrease in groups of higher concentration.With the increase in the concentration,the NH3-N in culture supernatant increased linearly.In present research,polysorbate 20 could greatly stimulate the degradation of cotton-straw in in vitro anaerobic fermentation.更多还原