Isolation and Characterization of a Naphthalene-Degrading Strain,Alcaligenes sp,A111

Naphthalene 분해균주 Alcaligenes sp. A111의 분리 및 특성

A bacterial strain which formed a distinct colony on agar plate containing naphthalene as a vapor phase and grew well ina liquid minimal medium was isolated and identified as Alcaligenes sp. A111. Optimum temperature and pH for the cultivation of Alcaligenes sp. A111 were 30$\cir$C and 7.0, respectively. Cell growth increased dramatically from 12 hours after inoculation and revealed a stationary phase at about 48 hours. Relative growth rate ($\mu$')increased hyperbolically depending on the conceration of naphthalene up to 500 ppm and reached to the maximum value pf 2.8/day, but $\mu$' didn't change within a range of 500~4000 ppm naphthalene. NH$_{4}$Cl or NH$_{4}$NO$_{3}$ was preferrd as a nitrogen source and a P : N ratio by weight og 6 : 1 was favorable to cell growth. Alcaligenes sp. A111 utilized the intermediates of degradation of naphthalene and showed tolerance to benzene, toluene, and octane. therefore, it is suggested that Alcaligenes sp. A111 could be effectively used for the biological treatment of wastewater containing naphthalene in the presence of some aromatic compounds.