三株真菌对重金属锰的耐受性和吸附特性研究

Tolerance of three fungal species to heavy metal manganese and the adsorption of the metal

摘要:

【目的】研究3种真菌对锰离子的耐受性，并研究其对溶液中Mn²⁺吸附的最佳条件和吸附机理，为治理锰离子污染提供技术参考。【方法】测定哈茨木霉（Trichoderma harzianum）、深绿木霉（Trichoderma atroviride）和棘孢木霉（Trichoderma asperellum）三株真菌的最低抑菌浓度（minimum inhibitory concentration，MIC），探究最佳吸附条件，并利用扫描电子显微镜（scanning electron microscopy-energy dispersive X-ray spectroscopy，SEM-EDS）和傅里叶变换红外光谱（Fourier transform infrared spectroscopy，FTIR）对吸附前后菌体进行分析。【结果】哈茨木霉、深绿木霉、棘孢木霉对重金属锰耐受的浓度可达到1 600、1 800、2 000 mg/L，最佳吸附条件为pH为7，吸附时间80 h，温度28℃，吸附率最高可达23.7%，哈茨木霉参与吸附的官能团有-OH、胺基中的-C-N-、-C=O。棘孢木霉参与吸附的官能团有-OH和-NH。深绿木霉参与吸附的官能团主要有-C-H、磷酸基团P=O、P-OH和PO₄^3-。【结论】哈茨木霉、深绿木霉、棘孢木霉对重金属锰有较好的吸附作用，可为治理土壤中的锰污染提供重要的参考和依据。

Abstract:

[Objective] To explore the tolerance of three fungal species to manganese ion, the optimal conditions for them to adsorb Mn²⁺ in solution, and the mechanism for the adsorption, and thus to provide technical reference for the control of manganese ion pollution.[Methods] The minimum inhibitory concentration (MIC) of Trichoderma harzianum, T. atroviride and T. asperellum was determined and the optimal adsorption conditions were explored. Based on scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) and Fourier transform infrared spectroscopy (FTIR), fungal cells before and after the adsorption were analyzed. [Results] T. harzianum, T. atroviride, and T. asperellum could tolerate the maximum manganese concentration of 1 600 mg/L, 1 800 mg/L, and 2 000 mg/L, respectively. The optimum adsorption conditions are pH 7, adsorption time of 80 h, and temperature of 28℃, and the highest adsorption rate was up to 23.7%. The functional groups involved in the adsorption of T. harzianum were -OH, and -C-N- and-C=O in the amine group, and those of T. asperellum were -OH and -NH. The functional groups of T. atroviride were -C-H, and phosphate groups P=O, P-OH, and PO₄^3-.[Conclusion] The screened T. harzianum, T. atroviride, and T. asperellum showed strong adsorption of heavy metal manganese, which can serve as a reference the treatment of manganese pollution in soil.