生物燃料将成为主要新能源之一,以玉米芯为原料,碱氧和稀酸为处理剂对其进行2步法预处理,使原料中纤维素相对含量增加,以提供转化乙醇的纤维素原料。采用扫描电镜表征2步法预处理玉米芯,其表面形成疏松、沟纹和孔洞形态,这有利于酶解。...生物燃料将成为主要新能源之一,以玉米芯为原料,碱氧和稀酸为处理剂对其进行2步法预处理,使原料中纤维素相对含量增加,以提供转化乙醇的纤维素原料。采用扫描电镜表征2步法预处理玉米芯,其表面形成疏松、沟纹和孔洞形态,这有利于酶解。采用瑞氏木霉生产的纤维素酶水解该预处理玉米芯,利用正交实验得到酶水解优化条件为,酶用量75 FPU g 1,底物质量浓度60 g L 1,pH值4.8,反应温度50℃,还原糖得率可达69.3%。为提高纤维素酶中β-葡聚糖酶的酶活效率,并减少产物葡萄糖对β-葡聚糖酶的抑制作用,进一步优化β-葡聚糖酶加量。结果表明,当β-葡聚糖酶加量达6.5 CBU时,还原糖得率显著提高到78.2%。这表明该预处理玉米芯是有效降解的玉米芯原料,适于提高还原糖得率。展开更多
Purification of biomass ethanol from the products of brown sugar yeast-fermentation produces a large amount of residue. This fermentation residue contains abundant brown sugar-derived nutrients and is mainly used as c...Purification of biomass ethanol from the products of brown sugar yeast-fermentation produces a large amount of residue. This fermentation residue contains abundant brown sugar-derived nutrients and is mainly used as compost or livestock feed. However, the in vivo physiological effects of oral residue ingestion are not known. The purpose of this study was to elucidate the physiological action and molecular mechanism of fermented brown sugar residue in nematode stress tolerance, aging, and lifespan using Caenorhabditis elegans. Fermented brown sugar residue was divided into two layers, supernatant and precipitate, and each was given to nematodes. Analysis of motility and survival rate under thermal stress revealed reduced mobility and increased survival rate following treatment with fermented brown sugar residue. The survival rate of nematodes under 1% H2O2 was markedly increased by the residue and mitochondrial membrane depolarization was induced and mitochondrial radical oxygen species levels increased. Furthermore, aging dependent reduction of motility was suppressed, and the average life span of nematodes was extended by treatment with fermented brown sugar residue. Moreover, the effects of fermented brown sugar residue on stress tolerance, lifespan elongation, and decreased aging dependent momentum reduction were lost in the daf-16 mutant. Taken together, our results show that the various physiological actions of fermented brown sugar residue, including stress tolerance and lifespan extension, occur via DAF-16.展开更多
基金中国石油大学(北京)科研基金(QZDX-2010-04)国家自然科学基金(21076229+1 种基金51274223)国家重大专项(2011 X 05009-005)
文摘生物燃料将成为主要新能源之一,以玉米芯为原料,碱氧和稀酸为处理剂对其进行2步法预处理,使原料中纤维素相对含量增加,以提供转化乙醇的纤维素原料。采用扫描电镜表征2步法预处理玉米芯,其表面形成疏松、沟纹和孔洞形态,这有利于酶解。采用瑞氏木霉生产的纤维素酶水解该预处理玉米芯,利用正交实验得到酶水解优化条件为,酶用量75 FPU g 1,底物质量浓度60 g L 1,pH值4.8,反应温度50℃,还原糖得率可达69.3%。为提高纤维素酶中β-葡聚糖酶的酶活效率,并减少产物葡萄糖对β-葡聚糖酶的抑制作用,进一步优化β-葡聚糖酶加量。结果表明,当β-葡聚糖酶加量达6.5 CBU时,还原糖得率显著提高到78.2%。这表明该预处理玉米芯是有效降解的玉米芯原料,适于提高还原糖得率。
文摘Purification of biomass ethanol from the products of brown sugar yeast-fermentation produces a large amount of residue. This fermentation residue contains abundant brown sugar-derived nutrients and is mainly used as compost or livestock feed. However, the in vivo physiological effects of oral residue ingestion are not known. The purpose of this study was to elucidate the physiological action and molecular mechanism of fermented brown sugar residue in nematode stress tolerance, aging, and lifespan using Caenorhabditis elegans. Fermented brown sugar residue was divided into two layers, supernatant and precipitate, and each was given to nematodes. Analysis of motility and survival rate under thermal stress revealed reduced mobility and increased survival rate following treatment with fermented brown sugar residue. The survival rate of nematodes under 1% H2O2 was markedly increased by the residue and mitochondrial membrane depolarization was induced and mitochondrial radical oxygen species levels increased. Furthermore, aging dependent reduction of motility was suppressed, and the average life span of nematodes was extended by treatment with fermented brown sugar residue. Moreover, the effects of fermented brown sugar residue on stress tolerance, lifespan elongation, and decreased aging dependent momentum reduction were lost in the daf-16 mutant. Taken together, our results show that the various physiological actions of fermented brown sugar residue, including stress tolerance and lifespan extension, occur via DAF-16.
