Figure 1.
Molecular structure of chlorpyrifos.
Table 1.
The symbols and levels of three independent variables used in central composite rotatable design (CCRD).
Figure 2.
Phylogenetic tree based on the 5.8S rRNA sequence of strain Hu-01 and related strains.
Numbers in parentheses represent the sequences accession number in GenBank. Numbers at the nodes indicate bootstrap values from the neighborhood-joining analysis of 1,000 resampled data sets. Bar represents sequence divergence.
Table 2.
Central composite rotatable design (CCRD) matrix and the response of dependent variable for chlorpyrifos degradation.
Table 3.
Analysis of variance (ANOVA) for the fitted quadratic polynomial model for chlorpyrifos degradation.
Table 4.
Effect estimates for the fitted quadratic polynomial model for chlorpyrifos degradation.
Figure 3.
Response surface plot showing the effects of temperature and culture time on chlorpyrifos degradation by strain Hu-01 with pH = 6.5.
Figure 4.
Mass spectra of 3,5,6-trichloro-2-pyridinol (TCP) produced from chlorpyrifos degradation by strain Hu-01.
A: sample; B: authentic standard TCP from the National Institute of Standards and Technology (NIST, USA) library database.
Figure 5.
The proposed pathway for the chlorpyrifos degradation by strain Hu-01.
Figure 6.
Degradation kinetics of chlorpyrifos and 3,5,6-trichloro-2-pyridinol (TCP) during biodegradation studies.
□, non-inoculated control (chlorpyrifos); △, non-inoculated control (TCP); ▪, introduction with strain Hu-01 (chlorpyrifos); ▴, introduction with strain Hu-01(TCP). Error bars represent the standard deviation of three replicates.
Table 5.
Kinetic parameters of degradation of chlorpyrifos and 3,5,6-trichloro-2-pyridinol (TCP) by strain Hu-01.