Potential Use of Rice Field Cyanobacterium Nostoc muscorum in the Evaluation of Butachlor Induced Toxicity and their Degradation

Abstract

In the present study, butachlor (5, 10, 20, 40 and 80 ppm) induced toxicity in Nostoc muscorum and their degradation was evaluated. The dose of butachlor dependent decreased in the cell survival and growth of N. muscorum was noticed. Scanning electron microscopy revealed the adverse impact on the cell size and shapes. Low concentrations of butachlor (10 and 20 ppm) induced the over expression of a polypeptides of 31.0 K Da and 42.7 K Da, respectively which could be responsible for developing resistance in the organism up to certain level. Further, the degradation product of butachlor as a result of metabolic activities of N. muscorum, identified by GC-MS analysis includes phenols and benzene dicarboxylic acid indicating the utilization of herbicide during active growth.

Keywords: Bioremediation; Butachlor; Cyanobacteria; GC-MS; SDS-PAGE; SEM.

Figure 1

effects of butachalar on cell survial of N. muscorum measured after 15 days.Mean ± SE. All the treatments are significantly different at P<0.01.

Figure 2

Scanning electron micrographs of N.muscorum treated with butachlor; (A) Control filament (B) 5ppm (C) 20ppm and (D) 80ppm.

Figure 3

Growth characteristic of N.muscorum under different concentration of butachalor in liquid medium. Mean ± SE with n=3.

Figure 4

The SDS-page of total protein of Nostoc muscorum treated with different concentrations of butachlor, lane 2 (Control), lane 3 (5ppp), lane 4 (10ppm) and lane 5 (20ppm). The polypeptide bands which became enhanced or appared in response to butachlor is indicated by arow.

Figure 5

GC-MS determination of butachlor degradation in media including the 5ppm herbicide performed after 72hrs of incubation (A) Total butachlor was found to be 0.408 mg/ml. (B) Mass spectra of butachlor (C) library match of butachlor (D) GCMS chromatogram in full scan.