载锌凹凸棒石黏土中锌的解吸及抑菌作用研究

摘要

The aim of the current study was to investigate the effect of inclusion level of zinc-bearing palygorskite (ZnBP), desorption time and the concentration of Na+and NH4+on the zinc desorption of ZnBP prepared by solid or liquid ion exchange in an artiifcial gastrointestinal pH environment of piglet. Meanwhile, the antibacterial activity of ZnBP on E. coli K88 was also evaluated. The results showed that the desorption rate of zinc was negatively correlated with inclusion level of ZnBP, but was positively associated with the concentration of Na+and NH4+. However, the desorption rate was not affected by desorption time. The desorption rate of ZnBP prepared by solid ion exchange was higher than that of ZnBP made using liquid ion exchange. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ZnBP prepared by solid ion exchange were 12.5 and 15.625 mg/mL, respectively. The corresponding values for ZnBP prepared by liquid ion exchange were 100 and 125 mg/mL, respectively. It was concluded that the desorption capacity and antibacterial activity of ZnBP prepared by solid ion exchange were superior than that of ZnBP made under liquid enviroment.%通过体外模拟仔猪胃肠道pH环境，研究固相和液相载锌凹凸棒石黏土（载锌凹土）添加量、解吸时间、Na+、NH4+浓度对载锌凹土中锌解吸的影响，以及载锌凹土对大肠杆菌K88的抑制作用。结果表明，载锌凹土中锌的解吸率与载锌凹土添加量呈负相关，与Na+和NH4+浓度成正相关，但随时间的变化规律不明显，固相载锌凹土解吸率高于液相载锌凹土；固相载锌凹土的最低抑菌质量浓度（MIC）和最小杀菌质量浓度（MBC）分别为12.5 mg/mL和15.625 mg/mL，液相载锌凹土的MIC和MBC分别为100 mg/mL和125 mg/mL。结果表明，固相载锌凹土在体外模拟胃肠道环境条件下的解吸速度较快，对大肠杆菌的抑菌作用较强。