青霉菌和镰刀菌对重金属Cd~(2+)、Cu~(2+)、Zn~(2+)和Pb~(2+)的吸附特性

研究了青霉菌和镰刀菌对重金属Cd2+、Cu2+、Zn2+和Pb2+的吸附特性,探讨了复合重金属和不同培养基对菌株吸附能力的影响.同时,采用察氏液体培养基(CDM)和马铃薯葡萄糖培养基(PDB)接种菌株,对不同种类和浓度的重金属进行吸附实验.结果表明,青霉菌和镰刀菌对Cd2+、Cu2+和Zn2+的吸附率随金属浓度的升高而下降,吸附量随金属浓度的增加先增大后减小;当浓度增加到较高值(300mg·L-1)时,Pb2+的吸附率开始下降,吸附量先逐渐增加后变化不大.菌丝体对重金属的吸附能力表现出一定的差异性,对Pb2+的吸附率和吸附量明显高于其他3种金属,CDM培养青霉菌对300mg·L-1Pb2+的最大吸附量达到34.80mg·g-1.多种重金属的复合抑制了菌丝体对重金属离子的吸附.不同菌丝体对复合重金属的吸附量差异性较大,PDB培养混合菌体对重金属离子的吸附率和吸附量均较大,并有明显的促进作用.CDM培养菌丝体对Pb2+的吸附量均高于PDB培养菌丝体.

Biosorption characteristics of heavy metals cadmium,copper,zinc,lead by Penicillium and Fusarium fungi

The aim of this paper was to study biosorption characteristics of Penicillium and Fusarium fungi to Cd2+, Cu2+, Zn2+, and Pb2+ and to explore the effects of multiple heavy metals and different growth media on the biosorption capacity of the fungi. Experiments were conducted in Czapek Dox medium (CDM) and Potato Dextrose Broth (PDB) medium with inoculation of the fungi with different concentrations of the various heavy metals. Results showed that adsorption rates of Cd2+, Cu2+, and Zn2+ by the fungi decreased with increasing metal concentration and amounts adsorbed by the fungi first increased, then decreased with the concentration. The adsorption rates of Pb2+ increased with the concentrations then began to decrease at a concentration of 300 mg·L-1, and the amount of Pb2+ adsorbed increased with the concentration up to 100 mg·L-1 then remained almost unchanged. The adsorption rates and amounts of Pb2+ adsorbed by the fungi were significantly higher than those of Cd2+, Cu2+, and Zn2+. The amount of Pb2+ adsorbed by Penicillium reached 34.80 mg·g-1 at a concentration of 300 mg·L-1 in CDM. Combinations of the heavy metals inhibited the biosorption of metallic ions by the fungi. The combined inoculation with Penicillium and Fusarium fungi greatly improved the biosorption of heavy metals compared with single fungi grown in PDB. With multiple heavy metals in the medium, the amounts of Pb2+ adsorbed by the fungi in CDM were higher than those in PDB.