Research On Preparation And Application Of Trichoderma Asperellum Capsules Agent On Reduce Heavy Metals

In recent years,microbial remediation has received much attention and developed rapidly,which has become an important means to control heavy metal pollution.A fungus,Trichoderma asperellum,was selected from a heavy metal contaminated soil and the fungus can withstand high concentrations of plumbum.It was also found that it could reduce the absorption of plumbum in plant growth processes.On this basis,Trichoderma asperellum fungi was used to make an production.The mycelium was obtained by liquid culture,and the freeze-dried powder was obtained from the mycelium.The final product,Trichoderma capsule agent,was made of the freeze-dried powder.The actual effect was tested by pot experiment.The soybean powder medium was selected,because it's spores more 24.2%than other liquid medium.In different drying methods,the effect of freeze-drying was better.By comparing different protective agent,the sucrose was selected and the concentration of sucrose was set at 5%.The number of effective viable cells was 250 million.The water content was(1.5 ±0.2)%.The degree of fineness was(90.4 ± 0.2)%.The pH value was 7 after 6 months.It meets the requirements of national standards.The sewage was treated with freeze-dried powder.The optimum pH value was 7,and the optimum temperature was 20?-30?.The adsorption saturation time was 3.5 h,the maximum addition was 3%.The maximum removal rate was 83.75%.It was found that the toxicity of Trichoderma asperellum powder on algae growth was low.Trichoderma capsules agent was made by freeze-dried powder.The embedding agent was sodium alginate.The curing agent was anhydrous calcium chloride.The concentration of sodium alginate and freeze-dried powder was 5:2.The concentration of sodium alginate was set at 2.5%.The concentration of anhydrous calcium chloride was set at 1.5%.The curing time was 1 h.It was sealed at room temperature after freeze-drying,and the germination effect was good after six months.Through pot experiment,the highest descent percentage of cabbage lead content was 52.13%,and the average descent percentage was 43.25%.