白腐真菌芘降解特性及其与细菌的协同降解

Characteristics of White Rot Fungus and Its Synergistic Action with Bacteria in Terms of Degradation of Pyrene

采用纯培养与混合培养的方式,研究了黄孢原毛平革菌(P. chrysosporium)对芘的降解特性及其与6株细菌(TC-01、TC-1、TC-3、TC-5、TC-6、TC-10)的协同降解作用。结果表明,20 d时芘总降解率为30%,前期以生物降解为主,后期以吸附作用为主;混合培养下,真菌与TC-01(铜绿假单胞菌)显示出最佳的协同作用,7 d降解率达到40%,较真菌纯培养提高了约20%;分别研究了真菌、细菌各自生长行为、降解率和表面张力值大小。结果表明:真菌菌丝体对细菌的固定作用显著促进了细菌的生长,而细菌存在的情况下则可以有效延缓真菌的衰亡。同时,混合培养下的表面张力值可降至31 mN/m,提高了高疏水性物质芘的溶解度。

The efficiency of degradation of pyrene by a species of fungus, P. chrysosporium, and its synergistic action with six strains of bacteria denominated TC-01, TC-1, TC-3, TC-5, TC-6 and TC-10 were studied with the adoption of both pure culture and mixed culture methods. The results showed that the total pyrene degradation rate of P. chrysosporium attained to approximately 30% for 20 d, with biodegradation mainly at the early stage and the adsorption at the later; and by mixed culture, fungus together with TC-01 （Pseudomonas aeruginosa） showed synergistic effect the best, the degradation rate reached 40% for 7 d, up 20% compared to the pure culture. Finally, the growth behavior, degradation rate and the surface tension value of fungus and bacteria were studied respectively, the findings suggested that mycelia could immobilize bacteria and promote their growths, and on other hand, the presence of bacteria could delay the decaying of fungi. Meanwhile, surface tension of the culture medium could be reduced to 31 mN/m under the condition of mixed culture, thus improving the solubility of pyrene that is highly hydrophobic.