Table 5 Main functional groups of Fourier Transform Infrared (FTIR) spectra before and after adsorption
Strain type | Before adsorption (cm−1) | After adsorption (cm−1) | Differences in shifts (cm−1) | Assignment |
|---|---|---|---|---|
Living | 3307.31 | 3367.98 | 60.67 | stretching vibration of O–H and N–H of saccharide |
1741.17 | 1728.50 | − 12.67 | C=O stretching vibrations from lipids | |
1185.71 | 1180.85 | − 4.86 | C–O and C–C stretching vibrations | |
Non-living | 3415.13 | 3305.50 | − 109.63 | stretching vibration of O–H and N–H of saccharide |
2979.51 | 2982.40 | 2.89 | C–H stretching vibrations | |
2934.62 | 2931.04 | − 3.58 | asymmetric C–H stretching vibration | |
1649.69 | 1656.34 | 6.65 | stretching vibration of C= O(amide I) | |
1544.36 | 1536.76 | − 7.6 | stretching vibration of C–N and deformation vibration of N–H (amide II) |