Studies On PVA-degrading Bacteria

From printing and dyeing actived sludge,7 kinds of PVA-degrading bacteria were isolated. They are P-1,symbiotic bacteriaB1+B2,P-2,P-3,P-4 and P-5. P-1 , Symbiotic bacteriaB1+B2 and P-2 were more efective than others,the transparent circle diameters are 4.4, 4.6, 4.0cm respectively. B1, B2 , P-1, P-2 were iedentified as Aureobacterium sp , Kurthia sp ,Planococcus sp , Arthrobacter sp respectively. The symbiotic bacteriaB1+B2 was examied .It is composed of B1 and B2.During PVA biodegradation,B1 produces a certain growth factor for B2,B2 produces PVA-degrating enzyme.The PVA-degrating characters of the symbiotic bacteria B1+B2 was examind.When the concentration of PVA was 0.1,0.5,1.0g/L respectively,more than 80% of PVA was degradated after 7 days. During the treatment of the dyeing and pringting wastewater, when the temperature was 30℃,the removel efficiency of CODCr was 69.75% ,the proper treating time was 12h . The PVA-degrating Characters of Arthrobacter sp.p-1 and Rodococcus sp. Strain J-5 were examied. When the concentration of PVA was lower than 1g/L, more than 80% of PVA was degradated by Arthrobacter sp.p-1 after 7 days, but the proper PVA concentration of Rodococcus sp. Strain J-5 was 2g/L. During the treatment of the dyeing and pringting wastewater,when the PVA concentration was low ,the PVA removal efficiency of Arthrobacter sp.p-1 was 10% more than Rodococcus sp. Strain J-5. The effect of temperature on Arthrobacter sp.p-1 was smaller than Rodococcus sp. Strain J-5. The PVA removal efficiency of Arthrobacter sp.p-1 was stable. Symbiotic bacteriaB1+B2, P-1, P-2, P-3, P-4, P-5 and J-5 were stochasticly combied. The optimum combinations were P-1P-2P-4J-5, P-1(Symbiotic bacteriaB1+B2)P-3J-5,(Symbiotic bacteriaB1+B2)P-4P-2P-1; P-2P-5,P-3(Symbiotic bacteriaB1+B2). Four kinds of bacteria in the combination (Symbiotic bacteriaB1+B2)J-5P-1P-3 were mixed by various ratios, as a rsult , (Symbiotic bacteriaB1+B2)2J-52P-13P-31, (Symbiotic bacteriaB1+B2)1J-52 P-12P-3 2, (Symbiotic bacteriaB1+B2)3J-53P-11P-33, total 3 kinds of combinations were optimum mixing ratios.