为实现餐饮废弃油料的高效转化利用,本文采用Aspen Plus V14模拟软件,设计了一套年产7万吨生物柴油的生产工艺流程。本工艺流程以甘油三酯为主要成分的餐饮废弃油料为原料,基于NaOH催化的碱催化酯交换反应制备生物柴油,并通过工艺参数...为实现餐饮废弃油料的高效转化利用,本文采用Aspen Plus V14模拟软件,设计了一套年产7万吨生物柴油的生产工艺流程。本工艺流程以甘油三酯为主要成分的餐饮废弃油料为原料,基于NaOH催化的碱催化酯交换反应制备生物柴油,并通过工艺参数优化提升产品收率与能源利用效率。模拟结果显示,该工艺可使生物柴油质量分数达到99.48%,副产甘油纯度为100%,甲醇回收率约91.86%;经工艺与热能集成优化后,冷、热公用工程能耗分别降低37.15%和37.06%,年节能量达5543.8kW。研究表明,优化后的工艺可实现生物柴油的高效精制,年产量满足7万吨设计要求,且产品理化指标符合《B5柴油》(GB/T 25199—2017)标准,为餐饮废弃油料制备生物柴油提供了可行的工艺方案与技术参考。展开更多
The article Jetting-based bioprinting:process,dispense physics,and applications,written by Wei Long Ng and Viktor Shkolnikov,was originally published electronically on the publisher’s internet portal on 12 July 2024 ...The article Jetting-based bioprinting:process,dispense physics,and applications,written by Wei Long Ng and Viktor Shkolnikov,was originally published electronically on the publisher’s internet portal on 12 July 2024 without open access.展开更多
Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium ch...Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames （ORFs） were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them （penT） was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily （MFS） and contains 12 transmembrane spanning domains （TMS）. During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid （PAA） and phenoxyacetic acid （POA）. Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane. Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames （ORFs） were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them （penT） was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily （MFS） and contains 12 transmembrane spanning domains （TMS）. During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid （PAA） and phenoxyacetic acid （POA）. Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane.展开更多
【目的】Pen a 1是虾中的主要过敏原,已知其5个抗原表位在过敏反应中起着决定性的作用。用全蛋白抗体和表位特异性抗体,检测Pen a 1经体外模拟胃液(simulated gastric fluid,SGF)消化后其抗原表位免疫原性的变化情况,为研究人体消化对Pe...【目的】Pen a 1是虾中的主要过敏原,已知其5个抗原表位在过敏反应中起着决定性的作用。用全蛋白抗体和表位特异性抗体,检测Pen a 1经体外模拟胃液(simulated gastric fluid,SGF)消化后其抗原表位免疫原性的变化情况,为研究人体消化对Pen a 1的影响机理及脱敏食品的制备提供理论依据。【方法】以刀额新对虾(metapenaeus ensis)为原材料,提取纯化虾过敏原Pen a 1,采用Fmoc化学法合成Pen a 1抗原表位的5个多肽片段(No.1—No.5),分别与载体蛋白KLH和牛血清蛋白BSA偶联制备人工免疫原和包被原。用Pen a 1和制备的多肽免疫原免疫新西兰纯种白兔获得全白蛋抗体和特异性表位抗体。参照美国药典模拟人体胃液的条件消化处理Pen a 1,利用SDS-PAGE和Tricine-SDS-PAGE观察消化后Pen a 1分子量变化;通过免疫印迹(Western-blot)定性观察Pen a 1消化后生成的新蛋白片段与各抗体的结合情况;再经竞争抑制酶联免疫吸附试验(ci-ELISA)定量检测消化后的Pen a 1和表位多肽与各抗体结合能力,从而得出Pen a 1经SGF消化后各抗原表位免疫原性的变化程度。【结果】SDS-PAGE结果显示Pen a 1随SGF消化时间的延长逐渐被降解,在22 kD处生成一些较稳定的新蛋白片段,Tricine-SDS-PAGE结果表明在1.7—18 k D之间无新蛋白片段生成。Western-blot表明消化后分解生成的小分子蛋白与六种抗体发生不同程度结合,其中全蛋白抗体和No.4抗体几乎与生成的所有小分子蛋白结合,在22 k D左右处生成的稳定新蛋白片段均与No.3、4、5抗体有较强的结合,而与No.1、2抗体结合较弱甚至无结合,表明该蛋白携带No.3、4、5表位,而基本无No.1、2表位。ci-ELISA结果显示,Pen a 1经SGF消化后对全蛋白抗体和5个表位抗体的抑制率均显著下降,说明经过消化后Pena1及其抗原表位的免疫原性均明显降低,各抗原表位消化稳定性排序为No.4>No.2>No.1>No.3>No.5,其中No.2、1、3之间无显著性差异;ci-ELISA检测表位多肽经消化后其免疫原性也显著下降,消化稳定性排序为No.1>No.2>No.3>No.4>No.5,其中No.2、3、4之间无显著性差异。结合免疫印迹结果可知No.4抗原表位消化稳定性最高,但其表位多肽消化稳定性没有显著高于其它所有表位多肽,说明在消化过程中Pen a 1结构对该表位起到一定的保护作用,使其保持较高的消化稳定性;No.1、2、3次之,3个表位间无显著性差异;No.5消化稳定性最差,表明Pen a 1空间结构对其无明显保护作用。【结论】建立了一种用表位抗体检测过敏原经模拟消化后抗原表位消化稳定性的方法。Pen a 1经SGF消化后,免疫原性降低,分解生成部分较稳定的蛋白片段,但仍具有致敏性;5个抗原表位中No.4消化稳定最高,No.5最差。展开更多
用Haake流变仪,对三元乙丙橡胶(EPDM)进行熔融接枝马来酸酐(MAH),考察了单体、引发剂(DCP)用量对接枝率的影响。结果表明,在EPDM接枝MAH的反应中,随着DCP用量的增加,接枝率增大;随着MAH用量的增加,接枝率趋于一个平衡值。PEN EPDM g ... 用Haake流变仪,对三元乙丙橡胶(EPDM)进行熔融接枝马来酸酐(MAH),考察了单体、引发剂(DCP)用量对接枝率的影响。结果表明,在EPDM接枝MAH的反应中,随着DCP用量的增加,接枝率增大;随着MAH用量的增加,接枝率趋于一个平衡值。PEN EPDM g MAH共混物韧性的测定可以在很宽的温度(21℃～118℃)和组分〔(0～14wt%)EPDM g MAH〕范围中进行。发现了增加温度和增加EPDM g MAH含量对EPDM g MAH增韧PEN的脆韧转变有相同的影响。展开更多
文摘为实现餐饮废弃油料的高效转化利用,本文采用Aspen Plus V14模拟软件,设计了一套年产7万吨生物柴油的生产工艺流程。本工艺流程以甘油三酯为主要成分的餐饮废弃油料为原料,基于NaOH催化的碱催化酯交换反应制备生物柴油,并通过工艺参数优化提升产品收率与能源利用效率。模拟结果显示,该工艺可使生物柴油质量分数达到99.48%,副产甘油纯度为100%,甲醇回收率约91.86%;经工艺与热能集成优化后,冷、热公用工程能耗分别降低37.15%和37.06%,年节能量达5543.8kW。研究表明,优化后的工艺可实现生物柴油的高效精制,年产量满足7万吨设计要求,且产品理化指标符合《B5柴油》(GB/T 25199—2017)标准,为餐饮废弃油料制备生物柴油提供了可行的工艺方案与技术参考。
文摘The article Jetting-based bioprinting:process,dispense physics,and applications,written by Wei Long Ng and Viktor Shkolnikov,was originally published electronically on the publisher’s internet portal on 12 July 2024 without open access.
基金supported by the grants from the Ministry of Science and Technology of China(Nos.2009CB118905 and 2010ZX09401-403)the Knowledge Innovation Program of the Chinese Academy of Sciences(Nos.KSCX2-EW-G-6 and KSCX2-EW-J-6)
文摘Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames （ORFs） were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them （penT） was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily （MFS） and contains 12 transmembrane spanning domains （TMS）. During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid （PAA） and phenoxyacetic acid （POA）. Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane. Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames （ORFs） were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them （penT） was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily （MFS） and contains 12 transmembrane spanning domains （TMS）. During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid （PAA） and phenoxyacetic acid （POA）. Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane.
文摘【目的】Pen a 1是虾中的主要过敏原,已知其5个抗原表位在过敏反应中起着决定性的作用。用全蛋白抗体和表位特异性抗体,检测Pen a 1经体外模拟胃液(simulated gastric fluid,SGF)消化后其抗原表位免疫原性的变化情况,为研究人体消化对Pen a 1的影响机理及脱敏食品的制备提供理论依据。【方法】以刀额新对虾(metapenaeus ensis)为原材料,提取纯化虾过敏原Pen a 1,采用Fmoc化学法合成Pen a 1抗原表位的5个多肽片段(No.1—No.5),分别与载体蛋白KLH和牛血清蛋白BSA偶联制备人工免疫原和包被原。用Pen a 1和制备的多肽免疫原免疫新西兰纯种白兔获得全白蛋抗体和特异性表位抗体。参照美国药典模拟人体胃液的条件消化处理Pen a 1,利用SDS-PAGE和Tricine-SDS-PAGE观察消化后Pen a 1分子量变化;通过免疫印迹(Western-blot)定性观察Pen a 1消化后生成的新蛋白片段与各抗体的结合情况;再经竞争抑制酶联免疫吸附试验(ci-ELISA)定量检测消化后的Pen a 1和表位多肽与各抗体结合能力,从而得出Pen a 1经SGF消化后各抗原表位免疫原性的变化程度。【结果】SDS-PAGE结果显示Pen a 1随SGF消化时间的延长逐渐被降解,在22 kD处生成一些较稳定的新蛋白片段,Tricine-SDS-PAGE结果表明在1.7—18 k D之间无新蛋白片段生成。Western-blot表明消化后分解生成的小分子蛋白与六种抗体发生不同程度结合,其中全蛋白抗体和No.4抗体几乎与生成的所有小分子蛋白结合,在22 k D左右处生成的稳定新蛋白片段均与No.3、4、5抗体有较强的结合,而与No.1、2抗体结合较弱甚至无结合,表明该蛋白携带No.3、4、5表位,而基本无No.1、2表位。ci-ELISA结果显示,Pen a 1经SGF消化后对全蛋白抗体和5个表位抗体的抑制率均显著下降,说明经过消化后Pena1及其抗原表位的免疫原性均明显降低,各抗原表位消化稳定性排序为No.4>No.2>No.1>No.3>No.5,其中No.2、1、3之间无显著性差异;ci-ELISA检测表位多肽经消化后其免疫原性也显著下降,消化稳定性排序为No.1>No.2>No.3>No.4>No.5,其中No.2、3、4之间无显著性差异。结合免疫印迹结果可知No.4抗原表位消化稳定性最高,但其表位多肽消化稳定性没有显著高于其它所有表位多肽,说明在消化过程中Pen a 1结构对该表位起到一定的保护作用,使其保持较高的消化稳定性;No.1、2、3次之,3个表位间无显著性差异;No.5消化稳定性最差,表明Pen a 1空间结构对其无明显保护作用。【结论】建立了一种用表位抗体检测过敏原经模拟消化后抗原表位消化稳定性的方法。Pen a 1经SGF消化后,免疫原性降低,分解生成部分较稳定的蛋白片段,但仍具有致敏性;5个抗原表位中No.4消化稳定最高,No.5最差。
文摘 用Haake流变仪,对三元乙丙橡胶(EPDM)进行熔融接枝马来酸酐(MAH),考察了单体、引发剂(DCP)用量对接枝率的影响。结果表明,在EPDM接枝MAH的反应中,随着DCP用量的增加,接枝率增大;随着MAH用量的增加,接枝率趋于一个平衡值。PEN EPDM g MAH共混物韧性的测定可以在很宽的温度(21℃～118℃)和组分〔(0～14wt%)EPDM g MAH〕范围中进行。发现了增加温度和增加EPDM g MAH含量对EPDM g MAH增韧PEN的脆韧转变有相同的影响。
