탈질조건에서 nitroglycerin의 생물학적 분해 동역학 및 미생물 군집 변화

Abstract

Biodegradation of an explosive compound, glyceryl trinitrate (GTN), was studied with a denitrifying microbial culturegrown in a sequencing batch reactor and a GTN acclimated denitrifying culture. The GTN acclimated culture, which werefed on GTN for 1 month, degraded GTN regioselectively via denitration on C1 position as compared to C2 positiondenitration by denitrifying culture that has never been exposed to GTN. Accumulation of two isomeric glyceryl dinitrates(GDNs) in both culture medium suggests that GDN denitration is the rate-limiting step in GTN biodegradation. The firstorder GTN degradation rate normalized to cell concentration of the acclimated culture was calculated to be 0.045 (±0.002)L/g-hr. Increasing concentration of electron acceptor(nitrate) resulted in discouraged GTN degradation. According tomicrobial community analysis, prolonged GTN exposure resulted in 25% increase in the genus level of the GTNacclimated culture with the disappearance of two dominating denitrifying microbial species of Methyloversatilisuniversalis and Hyphomicrobium zavarzinii in the denitrifying culture.