Pot-culture experiments were conducted to investigate the potential of microorganism- saponin assisted phytoremediation of cadmium (Cd) and benzo(a)pyrene (B[a]P) co-contaminated soil using Cd-hyperaccumulator Sedum alfredii. Results showed that B[a]P-degrading bacterium (Ochrobactrum intermedium B[a]P-16) inoculation significantly increased root (by 22.1-24.1%) and shoot (by 20.5-23.4%) biomass of S. alfredii, whereas the application of saponin had no effect on the growth of S. alfredii. The saponin solution at 2 g L^-1 extracted more Cd and B[a]P than water, saponin enhanced Cd and B[a]P bioavailability in soil and thus promoted their uptake and accumulation in S. alfredii. The activity of B[a]P-16, dehydrogenase and polyphenol oxidase in co-contaminated soil was promoted by growing S. alfredii, and the application of B[a]P-16 and saponins caused a significant (P<0.05) increase in both enzyme activities. The maximum B[a]P removal rate (82.0%) and Cd phytoextraction rate (19.5%) were obtained by co-application of S. alfredii with B[a]P-16 and saponin. The B[a]P-16 and plant promoted biodegradation were the predominant contributors towards removal of B[a]P from soil. A significant (P<0.05) synergistic effect of B[a]P-16 and saponin on B[a]P and Cd removal efficiency was observed in this study. It is suggested that planting S. alfredii with application of B[a]P-16 and saponin would be an effective method for phytoremediation of soil co-contaminated with Cd and PAHs.

进行盆栽试验以研究使用Cd-超蓄积苜蓿景天（Sedum alfredii）的微生物皂苷辅助修复镉（Cd）和苯并（a）re（B [a] P）共污染土壤的潜力。结果表明，B [a]芘降解菌（苍白杆菌媒介物苯并[a] P-16）接种显著增加的根（由22.1-24.1％）和拍摄（由20.5-23.4％）的生物量S.景天，而皂苷的施用对苜蓿链球菌的生长没有影响。2 g L ^-1的皂素溶液比水提取更多的Cd和B [a] P，皂素提高了土壤中Cd和B [a] P的生物利用度，从而促进了S. alfredii的吸收和积累。。种植苜蓿链球菌可促进土壤中B [a] P-16，脱氢酶和多酚氧化酶的活性，B [a] P- 16和皂苷的施用显着增加（P <0.05）在这两种酶的活动。通过将S. alfredii与B [a] P-16和皂苷共同应用，可获得最大的B [a] P去除率（82.0％）和Cd的植物提取率（19.5％）。B [a] P-16和植物促进的生物降解是从土壤中去除B [a] P的主要因素。在这项研究中观察到B [a] P-16和皂苷对B [a] P和Cd去除效率具有显着的（P <0.05）协同作用。建议种植苜蓿链球菌 B [a] P-16和皂苷的应用将是一种有效修复被Cd和PAHs共同污染的土壤的有效方法。