Biodegradation of Polyacrylamide by Bacteria Isolated from Sewage Sludge —— ZhengGuolin
Main Contents To choose a background Research methods Expected results
To choose a background Polyacrylamide(PAM)is a general term for acrylamide homopolymers and copolymers.As an important product of chemical industry with high-tech and high accessional values,polyacrylamide has been widely applied to different fields of industry and agriculture,and even to people’s daily life.
It was generally considered that polyacrylamide was an extraordinarily stable macro mole cularpolymer. But unfortunately, polyacrylamide is found with slow physical degradation (heat, cutting) , slow chemical degradation (hydrolysis , oxidation,catalysis oxidation) and slow biodegradation under natural conditions,and it finally produced different oligomers, as well as acrylamide, which possess neurotoxicity,and are directly and indirectly harmful to humanhealth.
as well as acrylamide, which possess neurotoxicity, and are directly and indirectly harmful to humanhealth. So,the studies on degradation of polyacrylamide are greatly inportant.However,there have been very few studies on biodegradation of polyacrylamide till now.
Research methods Strains of screening and separation Active sludge many microbial contact a period of time after just possess the inhibition of content degradation ability, Therefore need to sludge domestication. Will 100mL canister of sludge added to the container with 1000 mL beaker of based medium, In 35 ℃ thermostatic slot, use aquarium inflatable can aeration.
To cultivate activation, after 3 d every 72 h replacement 1 times and gradually increase the mixture containing poly sewage concentration ( polyacrylamide concentration: 50 ~ 500 mg, L - 1), cultivate domesticated after 45 d bacteria separated
With flat crossed separation by bacteria, will be placed in the℃ flat 37 biochemical incubator cultivate 48 h, then pick take different forms of colonies on flat crossed purification bacteria According to the colony morphology and microscope observation results, and repeat crossed separation, until they get the pure bacteria. Then again to the strains were on physiological and biochemical identification.
Expected Results some strain bacteria which degraded polyacrylamide were screened from activated sludge. One of the three strains,which could degrade polyacrylamide efficiently.