摘要：The harm caused by heavy metal lead to human health has always existed.Although the research on bioremediation of heavy metal pollution is relatively hot,the research on the application of heavy metal biosorbent in food and human body is still in its infancy.In response to this problem,this experiment takes 3 strains of yeasts with probiotic properties isolated from heavy metal pollution areas in Inner Mongolia as the research object,and do the yeast conducts analytical research on adsorption capacity and adsorption mechanism by using chemical modification groups,scanning electron microscopy and transmission electron microscopy combined energy spectroscopy,and Fourier infrared spectroscopy.The results show that the adsorption capacity of Wicker-hamomyces anomalus QF-l-lreaches the maximum value of 11.67±0.29 mg/g when the Pb2+ concentration is 800mg/L.The adsorption rate ofW.anomalus QF-1-1 reaches the maximum value of 99.26% when the Pb2+ concentration is 100mg/L.The more folds on the surface provide more adsorption sites for Pb2+ adsorption,and the bacterial cell structure changes after Pb2+ adsorption.The appearance of sediment on the bacterial surface after the adsorption of Pb2+ on the Wickerhamomyces anomalus QF-1-1(W.anomalus QF-1-1),Metschnikowia chrysoperlae QK-1-5 (M.chrysoperlae QK-1-5) and Rhodotorula muci-laginosa QD-2-6 (R.mucilaginosa QD-2-6) indicates that extracellular precipitation is an important mechanism for lead adsorption.The groups involved in the adsorption of Pb2+ on the cell wall include CN,NH,-OH,-HPO42",-COOH,etc.Among them,the three groups of carboxyl,amino and phosphoric acid groups contribute to the adsorption of Pb2+ by the three strains of amino group> carboxyl group > phosphate group.The activity of various groups directly affects the adsorption of Pb2+ by the three strains.The black sediment inside the bacteria after the adsorption of Pb2+ indicates that there is intracellular accumulation.W.anomalus QF-1-1 and R.mucilaginosa QD-2-6 adsorbs the Mg element in the energy spectrum after the adsorption of the precursor cells,indicating that the adsorption of Pb2+ played a role in ion exchange.The conclusions of this study will make yeasts as a new type of biosorbent applied in food to ensure food safety,and will play an important role in preventing and alleviating lead poisoning in humans and animals.
关键词：Green environmental protection;heavy metal lead;probiotic properties;adsorption capacity;adsorption mechanism
