Subjects: Biology >> Botany >> Applied botany submitted time 2018-10-26 Cooperative journals: 《广西植物》
Abstract： Leersia hexandra Swartz is the chromium hyper-accumulative plant which was found firstly in China. The endophytic bacteria of L. hexandra Swartz and their removal capacity for Cr(VI) were studied in this paper. A Cr(VI)-resistant endophytic bacterium G04 was isolated from the roots of L. hexandra Swartz by the solid plate culture method using the media of beef extract peptone containing Cr(VI). Biological identification results showed the strain belonged to Enterobacter cloacae. Effects of culture conditions, such as initial pH, temperature, Cr(VI) concentration, liquid volume, inoculation amount, shaking speed and culture time, on the removal rate of Cr(VI), removal rate of total Cr and the growth of the strain were studied in detail using the method of shaking flask culture. The results showed that the optimal conditions for the removal of Cr(VI) by E. cloacae G04 were as followed: initial pH of 5.0, culture temperature of 37 ℃, substrate concentration of 100 mg·L-1, liquid volume of 80 mL in 250 mL conical flask, inoculum size of 15%, shaking speed of 100 r·min-1 and culture time of 48 h.Under these conditions, the removal rate of Cr(VI) and total chromium were about 84% and 8%, respectively. The results of this study show that the endophytic bacteria Enterobacter cloacae G04 has better application potential for removing chromium. It may be used directly for remediation of soil and water environment contaminated of chromium, and also may be used as alternative strain for promoting plant remediation of chromium pollution. Furthermore, the result has an important reference value to illuminate the mechanism of chromium hyper-accumulation of L. hexandra Swartz.
Hits
Hits
Downloads
Comment