Table 1.
Purification profile of PHB depolymerase by various methods.
Table 2.
Purification of PHB depolymerase of Stenotrophomonas sp. RZS7 on Octyl sepharose column.
Table 3.
Qualitative measurement of biodegradation of PHB film.
Fig 1.
FTIR chromatogram of PHB (Control) read between 4000 to 500 cm-1 and analyzed with 1.40 software.
Fig 2.
FTIR chromatogram of PHB after degradation by Stenotrophomonas sp. RZS7 read between 4000 to 500 cm-1 and analyzed with 1.40 software. The functional groups present in the spectra were compared with the functional groups in control preparation.
Fig 3.
HPLC spectra of polymer before degradation (Control) recorded at 254 nm).
Spectral analysis was carried out at 254 nm with autochro-3000 software.
Fig 4.
HPLC spectra of polymer after degradation recorded at 254 nm.
The peaks were analyzed by using Autochro-3000 software and compared with the peaks of control.
Fig 5.
Chromatogram of polymer sample before biodegradation (Standard).
GC MS analysis was performed on gas chromatograph equipped with capillary column BP20 and mass spectrophotometer. The mass spectra obtained were recorded.
Fig 6.
Chromatogram of polymer sample after biodegradation.
GC MS analysis was performed by using gas chromatograph with turbomass GC capillary column BP20 and mass spectrophotometer. The mass spectra obtained were compared and identified with the library of spectra of standard methyl esters of PHB. The peaks were identified by matching relative retention time with respect to standard sample extracted at time zero.
Table 4.
GC MS analysis of methanolysed polymer before degradation (Standard) and after degradation.
Fig 7.
GC-MS spectra of polymer sample before degradation showing mass spectra of m/z = 29, 39, 41, 43, 45, 55, 57, 59, 74, 75, 87, 101, 111, 131, 143, 157, 171, 185, 199, 219, 227, 239, 265, 270, 271, 314, 415 indicating the presence of intact polymer of PHB.
Fig 8.
GC-MS spectra of polymer sample after degradation showing mass spectra of m/z 29, 32, 41, 43, 44, 55, 57, 69, 74, 75, 87, 97, 111, 129, 143, 145, 169, 176, 199, 220, 227, 270 indicating the presence of oligomers of PHB.
Fig 9.
Morphological changes in PHB film after soil burial test observed under FE SEM; (A) Control set, (B) PHB film buried in presence of natural soil, (C) PHB film degraded by Stenotrophomonas sp. RZS7.