Biodegradation of pyridine derivatives in soil suspensions

Abstract

Relationships between structure and biodegradability were evaluated for 28 pyridine derivatives in nutrient solutions inoculated with soil and incubated at 24°C. Compounds studied included pyridine; mono‐ and disubstituted pyridinecarboxylic acids; and hydroxy‐, chloro‐, amino‐and methylpyridines. Disappearance of the pyridine added was measured by UV spectrophotometry, and the ammonium released by cleavage of the pyridine ring was measured by colorimetry. Volatilization was estimated by analysis of the pyridines collected on the polyurethane foam stoppers used to plug the incubation vessels; sorption by soil was estimated from the initial decrease in solution concentration upon addition of soil. Pyridinecarboxylic acids, monohydroxypyridines and the unsubstituted pyridine ring did not volatilize and were degraded within 7 to 24 d. Methylpyridines were intermediate in degradability, disappearing in from less than 7 to more than 30 d. None of the aminopyridines was completely degraded in 30 d. Of the chloropyridines tested, only 4‐chloropyridine was completely degraded in 24 d. The susceptibility of 4‐chloropyridine to degradation may be attributed to the ease with which a chlorine group is removed from position 4 on the pyridine ring. No degradation was detected in 30 d for any of the other chloropyridines. Chloro‐and methylpyridines volatilized extensively.

Microbial metabolism of pyridine, quinoline, acridine, and their derivatives under aerobic and anaerobic conditions.

“…Experiments were conducted with batch cultures and soil suspensions, using various pyridine derivatives as substrates. These studies showed that pyridinecarboxylic acids had the highest transformation rate, followed by monohydroxypyridines, methylpyridines, aminopyridines, and chloropyridines (114,115). Carboxyl substituents at any position of the pyridine ring stimulated decomposition more than did any other substituent, whereas chlorosubstituted pyridines showed the lowest degradation rate (76).…”

Pressurized fluidized-bed hydroretorting of Eastern oil shales -- Sulfur control. Topical report for Subtask 3.1, In-bed sulfur capture tests; Subtask 3.2, Electrostatic desulfurization; Subtask 3.3, Microbial desulfurization and denitrification

“…The maximum charge qql that can be acquired by a particle in aic by triboelectrification is glven by the Gaussian limit (Cross, 1987), that is, 2 _ qm = _dp _oEb (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19) or maximum charge-to-ma_s ratio…”

Green removal of pyridine from water via adsolubilization with lignosulfonate intercalated layered double hydroxide

“…Thus, the removal of pyridine from wastewater is an important research topic worthy of detailed study. At present, many researchers have devoted themselves to develop effective and economical methods to deal with the wastewater containing pyridine and the common methods used for the removal of pyridine from wastewater mainly including photocatalysis (Zhao et al, 2004), membrane separation (Mandal and Bhattacharya, 2006), biological degradation (Lee et al, 1994;Rhee et al, 1996;Sims and Sommers, 1986), ozonation (Andreozzi et al, 1991), and so on. However, these methods often involve complex process, high cost, and even may lead to secondary pollution during removal process.…”