GT_lession_4_Biodegradn_NITP-2016.pdf
- 1. GREEN TECHNOLOGY (Environmental Science) SUB Code: CH104 Dr. Aniruddha Paul NATIONAL INSTITUTE OF TECHNOLOGY PATNA DEPARTMENT of CHEMISTRY 1 02/17/2016
- 2. UNIT 4: WATER and BIODEGRADATION Biodegradation A. Mineralization: 02/17/2016 2
- 3. B. Biotransformation: Example 1. Example 2. 02/17/2016 3
- 4. Biodegradation: Some General rules 02/17/2016 4
- 5. 02/17/2016 5 Biodegradation: Some General rules
- 6. 02/17/2016 6 Biodegradation: Some General rules
- 7. 02/17/2016 7 Biodegradation: Some General rules
- 8. 02/17/2016 8 Biodegradation: A list of transformation reactions CVCVV CVCVV
- 9. 02/17/2016 9 In both cases the first stage is formation of pyruvic acid from simple hexose (like glucose)
- 10. 02/17/2016 10
- 12. 02/17/2016 12 The acids can undergo further degradation, as shown in next section.
- 13. 02/17/2016 13 • The biodegradation of fats is difficult and is restricted by their limited solubility. • Oxidation occurs at β carbon atom – and proceeds in a series of steps. • Coenzyme A actively participate in this transformation. Step 1. α β
- 14. 02/17/2016 14 Step 2. Hydrogen removed from β carbon (Dehydrogenation) Step 3. Hydroxylation at β carbon α β α β α β α β
- 15. 02/17/2016 15 Step 4. Dehydrogenation α β Step 5. Hydrolysis (α-β bond cleavage) α β α β Original molecule of acid appears with as a new acid derivative with 2 less carbon atoms.
- 16. 02/17/2016 16 β oxidation of palmitic acid would proceed by “chopping off’ two carbons at a time in the form of acetic acid. Since the acid has total 16 carbons, a total 8 moles of acetic acid will be formed for each mole of palmitic acid. (7 cycles) Example: β Oxidation of Palmitic Acid (C15H31COOH) Biodegradation of detergents • Some are readily biodegradable: Common soaps, fatty acids, sulfated alcohols, esters etc. • Others have moderate to severe Bio resistivity: polymers of ethylene oxide (moderate), alkyl benzene sulfonates derived from propene (highly resistant). • Linear alkyl benzene sulfonates (LAS) are biodegradable alternative for most hazardous detergents.