| Present study | Present study | [15] | [9] |
Element | Range (%) | Mean ± Std dev | Range (%) | Mean |
Carbon | 55.3 - 58.7 | 55.34 ± 3.3 | 49.54 - 50.98 | 76.72 |
Oxygen | 4.14 - 4.88 | 4.1 ± 0.25 | - | - |
Hydrogen | 0.54 - 0.58 | 0.52 ± 0.02 | - | 1.73 |