Sodium cocoyl glycinate(SCG),an environmentally friendly anionic amino acid surfactant,is widely used in daily chemical products as an upgraded alternative to traditional surfactants.In this study,crude Camellia oleif...Sodium cocoyl glycinate(SCG),an environmentally friendly anionic amino acid surfactant,is widely used in daily chemical products as an upgraded alternative to traditional surfactants.In this study,crude Camellia oleifera saponin(COS)was purified using AB-8 macroporous adsorption resin,and its composition and structure were analyzed.The effects of different mole fractions of COS(αCOS)on surface tension(γ),oil-water interfacial tension(IFT),emulsification,and foam properties of COS-SCG binary mixed systems were investigated in mixtures of SCG with purified COS.The stability ofγand foamability under diverse environmental conditions were also discussed.The results indicated that the COS-SCG system exhibited remarkable surface-active synergism.The minimum critical micelle concentration(cmc)of the mixed system was lower than that of SCG,and adding a small mole fraction of COS(1%-2%)induced a synergistic reduction ofγ.Specifically,the cmc andγwere 2.50×10-4 mol/L and 23.1 mN/m forαCOS=1%,respectively.The system exhibited exceptional IFT reduction capacity,achieving a minimum value of 1.42 mN/m atαCOS=10%.The mixed system reached a foaming volume(atαCOS=50%)and foam stability(atαCOS=75%)were 51.0 mL and 97.37%,respectively.Microscopic analysis further confirmed these outstanding foam properties.Moreover,the COS-SCG system displayed reducedγwith enhanced foaming volume under elevated temperatures(35-75℃)and salinity(0-20 g/L).However,acidic conditions and hard water compromised bothγstability and foamability.展开更多
体系效能评估指标数量多、维数高,指标之间关联,且具有协同效应,加大了效能评估的计算复杂性。针对这一问题,建立考虑协同效应的联合作战体系效能指标灰色主成分分析(grey principal component analysis,GPCA)重构模型。首先,分析联合...体系效能评估指标数量多、维数高,指标之间关联,且具有协同效应,加大了效能评估的计算复杂性。针对这一问题,建立考虑协同效应的联合作战体系效能指标灰色主成分分析(grey principal component analysis,GPCA)重构模型。首先,分析联合防空作战体系的作战使命、任务、流程,构建其效能评估指标体系,并运用灰色关联模型分析指标间是否存在协同效应。其次,基于指标间存在的协同效应,给出3种重构效能评估指标体系的策略,并结合GPCA方法,构建具有协同效应的GPCA模型,对评估指标体系进行降维。最后,将所提方法应用于联合防空作战体系效能评估案例,筛选出具有协同效应的指标,重构效能评估指标体系。计算结果与方法对比分析表明,所提方法能够有效发现指标间的协同效应,重构后的评估指标体系保持了“同构性”。展开更多
OBJECTIVE To evaluate the synergistic effect of rosmarinic acid(RA)with antibiotics against Staphylococcus aureus(S.aureus)and MRSA and to identify the possible mechanism of action responsible for synergism if any.MET...OBJECTIVE To evaluate the synergistic effect of rosmarinic acid(RA)with antibiotics against Staphylococcus aureus(S.aureus)and MRSA and to identify the possible mechanism of action responsible for synergism if any.METHODS The antibacterial activity of Rosmarinic acid was studied for its zone of inhibition by agar well diffusion and MIC determination by liquid broth dilution technique against MRSA and VRSA.The synergistic effect of RA with antibiotics like amoxicillin,ofloxacin and vancomycin was evaluated by Broth checker board method and further confirmed with time kill kinetic studies.Microbial Surface Components Recognizing Adhesive Matrix Molecules(MSCRAMMs)were isolated by protein precipitation technique and its expression was studied by SDS PAGE.Further RA was evaluated for its beta lactamase inhibition property.RESULTS Rosmarinic acid exhibited antibacterial activity against S.aureus and MRSAby showing a MIC value of 0.8mg·mL-1 against S.aureus and 10mg·mL-1 against MRSA.Rosmarinic acid at 1/4X MIC value reduced the MIC of vancomycin,amoxicillin and ofloxacin by 1/4 times against S.aureus.But against MRSA,vancomycin was found to be synergistic.All the synergistic combinations have shown FIC value of 0.5.In order to measure the kinetics of the anti-bacterial activity,the bacterial growth rate with RA,antibiotics and synergistic combinations against S.aureus and MRSA was studied.It is observed that the synergistic combinations showed better time kill kinetics as compared to RA and antibiotics.Further RA could able to destruct the cell surface proteins MSCRAMMs which was studied by SDS PAGE.RA was also found to showβlactamase inhibiting property.CONCLUSION It is concluded that RA possess antibacterial activity but at a very higher concentration(in mg/mL)against S.aureus and MRSA.However it shows synergism with antibiotics and could able to reduce the MIC of antibiotics.Thus RA could be developed as an adjuvant for antibiotics against S.aureus and MRSA caused infections.Further studies are needed to identify the mechanism for its synergism with antibiotics.展开更多
文摘Sodium cocoyl glycinate(SCG),an environmentally friendly anionic amino acid surfactant,is widely used in daily chemical products as an upgraded alternative to traditional surfactants.In this study,crude Camellia oleifera saponin(COS)was purified using AB-8 macroporous adsorption resin,and its composition and structure were analyzed.The effects of different mole fractions of COS(αCOS)on surface tension(γ),oil-water interfacial tension(IFT),emulsification,and foam properties of COS-SCG binary mixed systems were investigated in mixtures of SCG with purified COS.The stability ofγand foamability under diverse environmental conditions were also discussed.The results indicated that the COS-SCG system exhibited remarkable surface-active synergism.The minimum critical micelle concentration(cmc)of the mixed system was lower than that of SCG,and adding a small mole fraction of COS(1%-2%)induced a synergistic reduction ofγ.Specifically,the cmc andγwere 2.50×10-4 mol/L and 23.1 mN/m forαCOS=1%,respectively.The system exhibited exceptional IFT reduction capacity,achieving a minimum value of 1.42 mN/m atαCOS=10%.The mixed system reached a foaming volume(atαCOS=50%)and foam stability(atαCOS=75%)were 51.0 mL and 97.37%,respectively.Microscopic analysis further confirmed these outstanding foam properties.Moreover,the COS-SCG system displayed reducedγwith enhanced foaming volume under elevated temperatures(35-75℃)and salinity(0-20 g/L).However,acidic conditions and hard water compromised bothγstability and foamability.
文摘红枣(Ziziphus jujuba Mill.)是具有极高营养价值和药用价值的山西特色果品,但关于不同菌种发酵枣汁中的差异代谢物的研究还较少。为揭示不同菌种发酵骏枣汁的代谢产物差异性,该文以交城骏枣为研究对象,通过添加植物乳植杆菌(Lactiplantibacillus plantarum)、嗜酸乳杆菌(Lactobacillus acidophilus)以及两菌联用协同发酵骏枣汁,采用超高效技术,对骏枣原汁及不同菌种发酵骏枣汁进行非靶向代谢组学研究。结果表明,联用协同菌种发酵的骏枣汁效果最佳。不同发酵菌种骏枣汁与原汁之间及不同发酵菌种骏枣汁之间的主要差异代谢物有6类,分别为有机酸类、有机碱类、氨基酸类、糖类、酚类和核苷类。京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)代谢通路发现,只有单菌与联用协同发酵骏枣汁的主要差异代谢物有不重合的代谢通路,为氨基酸代谢通路。该研究分析了不同菌种发酵骏枣汁之间以及发酵骏枣汁同骏枣原汁之间的代谢产物差异性,所检测到的物质可为发酵骏枣汁的分析及相应生物学功能研究提供一定的数据支持。
文摘体系效能评估指标数量多、维数高,指标之间关联,且具有协同效应,加大了效能评估的计算复杂性。针对这一问题,建立考虑协同效应的联合作战体系效能指标灰色主成分分析(grey principal component analysis,GPCA)重构模型。首先,分析联合防空作战体系的作战使命、任务、流程,构建其效能评估指标体系,并运用灰色关联模型分析指标间是否存在协同效应。其次,基于指标间存在的协同效应,给出3种重构效能评估指标体系的策略,并结合GPCA方法,构建具有协同效应的GPCA模型,对评估指标体系进行降维。最后,将所提方法应用于联合防空作战体系效能评估案例,筛选出具有协同效应的指标,重构效能评估指标体系。计算结果与方法对比分析表明,所提方法能够有效发现指标间的协同效应,重构后的评估指标体系保持了“同构性”。
基金The project supported by TEQIP PhaseⅡgrant under Anna University BIT campus,Tiruchirappalli-620024,Tamilnadu,India
文摘OBJECTIVE To evaluate the synergistic effect of rosmarinic acid(RA)with antibiotics against Staphylococcus aureus(S.aureus)and MRSA and to identify the possible mechanism of action responsible for synergism if any.METHODS The antibacterial activity of Rosmarinic acid was studied for its zone of inhibition by agar well diffusion and MIC determination by liquid broth dilution technique against MRSA and VRSA.The synergistic effect of RA with antibiotics like amoxicillin,ofloxacin and vancomycin was evaluated by Broth checker board method and further confirmed with time kill kinetic studies.Microbial Surface Components Recognizing Adhesive Matrix Molecules(MSCRAMMs)were isolated by protein precipitation technique and its expression was studied by SDS PAGE.Further RA was evaluated for its beta lactamase inhibition property.RESULTS Rosmarinic acid exhibited antibacterial activity against S.aureus and MRSAby showing a MIC value of 0.8mg·mL-1 against S.aureus and 10mg·mL-1 against MRSA.Rosmarinic acid at 1/4X MIC value reduced the MIC of vancomycin,amoxicillin and ofloxacin by 1/4 times against S.aureus.But against MRSA,vancomycin was found to be synergistic.All the synergistic combinations have shown FIC value of 0.5.In order to measure the kinetics of the anti-bacterial activity,the bacterial growth rate with RA,antibiotics and synergistic combinations against S.aureus and MRSA was studied.It is observed that the synergistic combinations showed better time kill kinetics as compared to RA and antibiotics.Further RA could able to destruct the cell surface proteins MSCRAMMs which was studied by SDS PAGE.RA was also found to showβlactamase inhibiting property.CONCLUSION It is concluded that RA possess antibacterial activity but at a very higher concentration(in mg/mL)against S.aureus and MRSA.However it shows synergism with antibiotics and could able to reduce the MIC of antibiotics.Thus RA could be developed as an adjuvant for antibiotics against S.aureus and MRSA caused infections.Further studies are needed to identify the mechanism for its synergism with antibiotics.
