采用添加 Ca CO3 和 HCl的方法研究了 p H对出芽短梗霉多糖发酵的影响规律。在 P2培养基中发酵2 4 h,该菌有一个强烈的产酸期 ,导致 p H迅速下降到 3.6左右。在此 p H环境下继续发酵 12 0 h,多糖产量仅为 5.9g/ L。如果用 MP2培养基 (P2...采用添加 Ca CO3 和 HCl的方法研究了 p H对出芽短梗霉多糖发酵的影响规律。在 P2培养基中发酵2 4 h,该菌有一个强烈的产酸期 ,导致 p H迅速下降到 3.6左右。在此 p H环境下继续发酵 12 0 h,多糖产量仅为 5.9g/ L。如果用 MP2培养基 (P2 + 0 .5% Ca CO3 )发酵 ,由于 Ca CO3 缓冲了发酵 p H的下降 ,在整个发酵过程中 p H值可以维持在 5.0以上 ,多糖产量达到 31g/ L。该菌的多糖合成不仅与发酵初始 p H有关 ,关键还在于整个发酵过程中发酵 p H值必须维持在 5.0以上。展开更多
利用LC-MS/MS对F.nucleatum的蛋白质表达谱进行了深入研究,共鉴定到1198个蛋白质的表达,占基因组58%的编码基因.通过在p H 6.5(癌症组织p H环境)和p H 7.5(正常组织p H环境)两种条件下F.nucleatum蛋白质表达的定量蛋白质组学分析,发现...利用LC-MS/MS对F.nucleatum的蛋白质表达谱进行了深入研究,共鉴定到1198个蛋白质的表达,占基因组58%的编码基因.通过在p H 6.5(癌症组织p H环境)和p H 7.5(正常组织p H环境)两种条件下F.nucleatum蛋白质表达的定量蛋白质组学分析,发现处于癌症微环境p H条件下蛋白质表达的变化明显集中于金属离子转运,硫胺素代谢,糖代谢等过程和功能.产丁酸发酵的能量代谢通路中的七个代谢酶在蛋白质组数据中找到,其中有五个在癌症p H条件下显著下调,这五个酶包含了丁酸盐代谢的整个过程,这为结直肠癌患者肠道丁酸盐含量降低提供了新的证明.此外,癌症p H条件下F.nucleatum的丁酸代谢受到抑制,造成产丁酸能力下降,可能是其促进结直肠癌发展在代谢水平上的原因之一.展开更多
Aim To investigate the relationship between pH environment of meptazinolhydrochloride (MEP) and its nasal absorption. Methods In situ nasal peifusion was performed to studythe effect of pH environment on the nasal abs...Aim To investigate the relationship between pH environment of meptazinolhydrochloride (MEP) and its nasal absorption. Methods In situ nasal peifusion was performed to studythe effect of pH environment on the nasal absorption. Its effect on the transport from nose tobrain was further researched by in vivo experiment. Results In in situ perfusion experiment, thenasal absorption of MEP in basic environment was significantly higher than that in acid condition,but the difference was not observed in in vivo experiment. Conclusion The pH environment ofmeptazinol hydrocloride in formulation cannot be regarded as an important factor influencing nasalabsorption and transport from nose to brain.展开更多
文摘采用添加 Ca CO3 和 HCl的方法研究了 p H对出芽短梗霉多糖发酵的影响规律。在 P2培养基中发酵2 4 h,该菌有一个强烈的产酸期 ,导致 p H迅速下降到 3.6左右。在此 p H环境下继续发酵 12 0 h,多糖产量仅为 5.9g/ L。如果用 MP2培养基 (P2 + 0 .5% Ca CO3 )发酵 ,由于 Ca CO3 缓冲了发酵 p H的下降 ,在整个发酵过程中 p H值可以维持在 5.0以上 ,多糖产量达到 31g/ L。该菌的多糖合成不仅与发酵初始 p H有关 ,关键还在于整个发酵过程中发酵 p H值必须维持在 5.0以上。
文摘利用LC-MS/MS对F.nucleatum的蛋白质表达谱进行了深入研究,共鉴定到1198个蛋白质的表达,占基因组58%的编码基因.通过在p H 6.5(癌症组织p H环境)和p H 7.5(正常组织p H环境)两种条件下F.nucleatum蛋白质表达的定量蛋白质组学分析,发现处于癌症微环境p H条件下蛋白质表达的变化明显集中于金属离子转运,硫胺素代谢,糖代谢等过程和功能.产丁酸发酵的能量代谢通路中的七个代谢酶在蛋白质组数据中找到,其中有五个在癌症p H条件下显著下调,这五个酶包含了丁酸盐代谢的整个过程,这为结直肠癌患者肠道丁酸盐含量降低提供了新的证明.此外,癌症p H条件下F.nucleatum的丁酸代谢受到抑制,造成产丁酸能力下降,可能是其促进结直肠癌发展在代谢水平上的原因之一.
文摘Aim To investigate the relationship between pH environment of meptazinolhydrochloride (MEP) and its nasal absorption. Methods In situ nasal peifusion was performed to studythe effect of pH environment on the nasal absorption. Its effect on the transport from nose tobrain was further researched by in vivo experiment. Results In in situ perfusion experiment, thenasal absorption of MEP in basic environment was significantly higher than that in acid condition,but the difference was not observed in in vivo experiment. Conclusion The pH environment ofmeptazinol hydrocloride in formulation cannot be regarded as an important factor influencing nasalabsorption and transport from nose to brain.
